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From: Ed Uthman <[e-mail]>
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Subject: Biopsy Report Guide (monthly posting, 38K, v. 1.2)
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Summary: Explanation of the pathologist's report on biopsies,
 aimed at the educated layperson.
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              The Biopsy Report: A Patient's Guide

               Ed Uthman, MD ([e-mail])
             Diplomate, American Board of Pathology

INTRODUCTION

Many medical conditions, including all cases of cancer, must be
diagnosed by removing a sample of tissue from the patient and
sending it to a pathologist for examination. This procedure is
called a biopsy, a Greek-derived word that may be loosely translated
as "view of the living." Any organ in the body can be biopsied using
a variety of techniques, some of which require major surgery (e.g.,
staging splenectomy for Hodgkin's disease), while others do not even
require local anesthesia (e.g., fine needle aspiration biopsy of
thyroid, breast, lung, liver, etc). After the biopsy specimen is
obtained by the doctor, it is sent for examination to another
doctor, the anatomical pathologist, who prepares a written report
with information designed to help the primary doctor manage the
patient's condition properly.

The pathologist is a physician specializing in rendering medical
diagnoses by examination of tissues and fluids removed from the
body. To be a pathologist, a medical graduate (M.D. or D.O.)
undertakes a five-year residency training program, after which he or
she is eligible to take the examination given by the American Board
of Pathology. On successful completion of this exam, the pathologist
is "Board-certified." Almost all American pathologists practicing in
JCAHO-accredited hospitals and in reputable commercial labs are
either Board-certified or Board-eligible (a term that designates
those who have recently completed residency but have not yet passed
the exam). There is no qualitative difference between
M.D.-pathologists and D.O.- pathologists, as both study in the same
residency programs and take the same Board examinations.

TYPES OF BIOPSIES

    1. Excisional biopsy. A whole organ or a whole lump is
       removed (excised). These are less common now, since the
       development of fine needle aspiration (see below). Some types
       of tumors (such as lymphoma, a cancer of the lymphocyte blood
       cells) have to be examined whole to allow an accurate
       diagnosis, so enlarged lymph nodes are good candidates for
       excisional biopsies. Some surgeons prefer excisional biopsies
       of most breast lumps to ensure the greatest diagnostic
       accuracy. Some organs, such as the spleen, are dangerous to
       cut into without removing the whole organ, so excisional
       biopsies are preferred for these.

       A special type of excisional biopsy of the breast is the
       needle localization biopsy, also called the "wire-guided
       biopsy." This is used when the patient presents with an
       abnormal mammogram, but no lump can be felt in the breast.
       Since the surgeon cannot feel anything, it is necessary for
       the radiologist, who can see the abnormality on the x-ray, to
       provide some sort of guide. While the patient is positioned
       in the mammography machine, the radiologist (a physician who
       specializes in diagnostic imaging) uses the mammogram and a
       special grid to insert a needle directly into the abnormal
       area. When a follow-up mammogram determines the needle is in
       the right place, a wire with a barb on the end is inserted
       through the hollow needle into the abnormal area. The needle
       is withdrawn from around the wire, leaving the wire fixed in
       place (because of the barb, it cannot fall out). The surgeon
       then cuts into the breast and follows the wire to the area in
       question, removes this area, and sends it to the pathologist.
       The pathologist then determines if the appropriate tissue has
       been removed and advises the surgeon appropriately. In some
       cases, it is necessary to x-ray the actual biopsy specimen to
       determine if the suspicious area has been removed.

    2. Incisional biopsy. Only a portion of the lump is removed
       surgically. This type of biopsy is most commonly used for
       tumors of the soft tissues (muscle, fat, connective tissue)
       to distinguish benign conditions from malignant soft tissue
       tumors, called sarcomas.

    3. Endoscopic biopsy.This is probably the most commonly
       performed type of biopsy. It is done through a fiberoptic
       endoscope the doctor inserts into the gastrointestinal tract
       (alimentary tract endoscopy), urinary bladder (cystoscopy),
       abdominal cavity (laparoscopy), joint cavity (arthroscopy),
       mid-portion of the chest (mediastinoscopy), or trachea and
       bronchial system (laryngoscopy and bronchoscopy), either
       through a natural body orifice or a small surgical incision.
       The endoscopist can directly visualize an abnormal area on
       the lining of the organ in question and pinch off tiny bits
       of tissue with forceps attached to a long cable that runs
       inside the endoscope.

    4. Colposcopic biopsy.This is a gynecologic procedure that
       typically is used to evaluate a patient who has had an
       abnormal Pap smear. The colposcope is actually a close-
       focusing telescope that allows the physician to see in detail
       abnormal areas on the cervix of the uterus, so that a good
       representation of the abnormal area can be removed and sent
       to the pathologist.

    5. Fine needle aspiration (FNA) biopsy.This is an
       extremely simple technique that has been used in Sweden for
       decades but has only been developed widely in the US over the
       last ten years. A needle no wider than that typically used to
       give routine injections (22 to 25 gauge) is inserted into a
       lump (tumor), and a few tens to thousands of cells are drawn
       up (aspirated) into a syringe. These are smeared on a slide,
       stained, and examined under a microscope by the pathologist.
       A diagnosis can often be rendered in a few minutes. Tumors of
       deep, hard-to-get-to structures (pancreas, lung, and liver,
       for instance) are especially good candidates for FNA, as the
       only other way to sample them is with major surgery. Such FNA
       procedures are typically done by a radiologist under guidance
       by ultrasound or computed tomography (CT scan) and require no
       anesthesia, not even local anesthesia. Thyroid lumps are also
       excellent candidates for FNA.

       Because of recent interest in cost containment, FNA is now
       widely applied in diagnosing breast lumps. While the
       technique is excellent in experienced hands, false negatives
       and false positives do occur. A false negative causes delay
       in diagnosis of breast cancer allowing the tumor to grow and
       spread, and a false positive is likely to result in an
       unnecessary mastectomy. I would therefore offer the following
       recommendations to any patient who has been encouraged to
       have a breast FNA:

              Studies have clearly shown that the diagnostic accuracy
              of breast FNA is optimal when the same person who
              interprets the smears also performs the biopsy itself.
              Accordingly, I recommend that patients have the actual
              procedure performed by a pathologist who does a good
              number of these cases as a part of his or her practice.

              FNAs that are positive for cancer should be confirmed
              by frozen section at the time of surgery, before the
              mastectomy is performed.

              An FNA that shows no cancer cells is no assurance that
              the patient does not have cancer. A negative FNA means
              that either 1) the patient does not have cancer, or 2)
              the patient does have cancer, but the needle missed the
              diagnostic cells.

    6. Stereotactic needle biopsy. This relatively new technique
       for evaluating breast lesions attempts to combine the
       advantages of FNA (no scar, no anesthesia, inexpensive),
       excisional biopsy (acquisition of solid pieces of tissue
       rather than smears) and needle localization (precise guidance
       by x-ray or ultrasound imaging). The patient lies on her
       abdomen, so that the breast hangs down into a space that can
       be x-rayed by a computerized imaging device. The computer
       displays the mammographic image on a screen. The radiologist
       identifies the abnormality and marks it electronically on the
       screen. The computer then positions a movable arm directly
       over the abnormal area. A biopsy device is attached to the
       arm, and the spring-loaded gun quickly inserts a hollow
       biopsy needle into the breast. The needle is removed, and the
       tissue it contains is sent to the pathologist for diagnosis.

       The downside of stereotactic needle biopsy is that, because
       only a tiny amount of tissue is removed, a negative result is
       no guarantee the patient does not have cancer. Another
       problem is that occasionally the biopsy will remove the
       portions of the lesion that were responsible for its being
       identified as abnormal in the first place. This leaves the
       surgeon with no "signpost" to follow in trying to remove by
       lumpectomy a cancer that was diagnosed by stereotactic needle
       biopsy.

    7. Punch biopsy. This technique is typically used by
       dermatologists to sample skin rashes and small masses. After
       a local anesthetic is injected, a biopsy punch, which is
       basically a small (3 or 4 mm in diameter) version of a cookie
       cutter, is used to cut out a cylindrical piece of skin. The
       hole is typically closed with a suture and heals with minimal
       scarring.

    8. Bone marrow biopsy. In cases of abnormal blood counts,
       such as unexplained anemia, high white cell count, and low
       platelet count, it is necessary to examine the cells of the
       bone marrow. In adults, the sample is usually taken from the
       pelvic bone, typically from the posterior superior iliac
       spine. This is the prominence of bone on either side of the
       pelvis underlying the "bikini dimples" on the lower
       back/upper buttocks. Hematologists do bone marrow biopsies
       all the time, but most internists and pathologists and many
       family practitioners are also trained to perform this
       procedure.

       With the patient lying on his/her stomach, the skin over the
       biopsy site is deadened with a local anesthetic. The needle
       is then inserted deeper to deaden the surface membrane
       covering the bone (the periosteum). A larger rigid needle
       with a very sharp point is then introduced into the marrow
       space. A syringe is attached to the needle and suction is
       applied. The marrow cells are then drawn into the syringe.
       This suction step is occasionally uncomfortable, since it is
       impossible to deaden the inside of the bone. The contents of
       the syringe, which to the naked eye looks like blood with
       tiny chunks of fat floating around in it, is dropped onto a
       glass slide and smeared out. After staining, the cells are
       visible to the examining pathologist or hematologist.

       This part of procedure, the aspiration, is usually followed
       by the core biopsy, in which a slightly larger needle is used
       to extract core of bone. The calcium is removed from the bone
       to make it soft, the tissue is processed (see "Specimen
       Processing," below) and tissue sections are made. Even though
       the core biopsy procedure involves a bigger needle, it is
       usually less painful than the aspiration.

SPECIMEN PROCESSING

After the specimen is removed from the patient, it is processed in
one or both of two major ways:

    1. Histologic sections. This involves preparation of stained,
       thin (less than 5 micrometers, or 0.005 millimeters) slices
       mounted on a glass slide, under a very thin pane of glass
       called a coverslip. There are two major techniques for
       preparation of histologic sections:

              a. Permanent sections. This technique gives the
              best quality of specimen for examination, at the
              expense of time. The fresh specimen is immersed in a
              fluid called a fixative for several hours (the
              necessary time dependent on the size of the specimen).
              The fixative, typically formalin (a 10% solution of
              formaldehyde gas in buffered water), causes the
              proteins in the cells to denature and become hard and
              "fixed." Adequate fixation is probably the most
              important technical aspect of biopsy processing.

              The fixed specimen is then placed in a machine that
              automatically goes through an elaborate overnight cycle
              that removes all the water from the specimen and
              replaces it with paraffin wax. The next morning, a
              technical professional, called a histologic technician,
              or "histotech," removes the paraffin-impregnated
              specimen and "embeds" it in a larger bloc of molten
              paraffin. This is allowed to solidify by chilling and
              is set in a cutting machine, called a microtome. The
              histotech uses the microtome to cut thin sections of
              the paraffin block containing the biopsy specimen.
              These delicate sections are floated out on a water bath
              and picked up on a glass slide.

              The the paraffin is dissolved from the tissue on the
              slide. With a series of solvents, water is restored to
              the sections, and they are stained in a mixture of
              dyes. The most common dyes used are hematoxylin, a
              natural product of the heartwood of the logwood tree,
              Haematoxylon campechianum, which is native to Central
              America, and eosin, an artifcial aniline dye. The stain
              combination, casually referred to by pathologists as "H
              and E" yields pink, orange, and blue sections that make
              it easier for us to distinguish different parts of
              cells. Typically, the nucleus of cells stains dark
              blue, while the cytoplasm stains pink or orange.

              b. Frozen sections. This technique allows one to
              examine histologic sections within a few minutes of
              removing the specimen from the patient, but the price
              paid is that the quality of the sections is not nearly
              as good as those of the permanent section. Still, a
              skilled pathologist and a knowledgeable surgeon can
              work together to use the frozen section's rapid
              availability to the patient's great benefit.

    2. Smears. The specimen is a liquid, or small solid chunks
       suspended in liquid. This material is smeared on a microscope
       slide and is either allowed to dry in air or is "fixed" by
       spraying or immersion in a liquid. The fixed smears are then
       stained, coverslipped, and examined under the microscope.

Like the frozen section, smear preparations can be examined within a
few minutes of the time the biopsy was obtained. This is especially
useful in FNA procedures (see above), in which a radiologist is
using ultrasound or CT scan to find the area to be biopsied. He or
she can make one "pass" with the needle and immediately give the
specimen to the pathologist, who can within a few minutes determine
if a diagnostic specimen was obtained. The procedure can be
terminated at that point, sparing the patient the discomfort and
inconvenience of repeated sticks.

PATHOLOGIC EXAMINATION

A. THE GROSS DESCRIPTION

The pathologist begins the examination of the specimen by dictating
a description of the specimen as it looks to the naked eye. This is
the "gross exam" or the "gross." Some pathologists may refer to the
gross exam as the "macroscopic." Most biopsies are small,
nondescript bits of tissue, so the gross description is brief and
serves mostly as a way to code which biopsy came from what area and
to use for troubleshooting if there is a question of specimen
mislabeling. A typical gross description of an endoscopic colon
biopsy follows:

       "Polyp of sigmoid colon." An ovoid, smooth- surfaced,
       firm, pale tan nodule, measuring 0.6 x 0.4 x 0.3 cm.
       Cassette 'A', all, bisected.

In the above example, the first item (in quotes) is an exact
recitation of how the specimen was labeled by the doctor who took
the biopsy. After that is a textual description of what the specimen
looked like, followed by measurements indicating its size. The
"Cassette 'A', all, bisected" phrase indicates that the specimen was
cut in half ("bisected"), submitted for tissue processing in its
entirety ("all") in a small container (cassette) labeled "A," which
will eventually be placed in the tissue processor.

Larger organs removed as biopsies have correspondingly longer and
more detailed gross descriptions. The following is the gross
description of a spleen removed to assess whether Hodgkin's disease
(a cancer of lymph tissues) has spread into it:

       "Spleen". An entire spleen, weighing 127 grams, and
       measuring 13.0 x 4.1 x 9.2 cm. The external surface is
       smooth, leathery, homogeneous, and dark purplish-brown.
       There are no defects in the capsule. The blood vessels
       of the hilum of the spleen are patent, with no thrombi
       or other abnormalities. The hilar soft tissues contain
       a single, ovoid, 1.2-cm lymph node with a dark grey cut
       surface and no focal lesions

       On section of the spleen at 2 to 3 mm intervals, there
       are three well-defined pale-grey nodules on the cut
       surface, ranging from 0.5 to 1.1 cm in greatest
       dimension. The remainder of the cut surface is
       homogeneous, dark purple, and firm.

       Summary of cassettes: 1, hilar blood vessels; 2, hilar
       lymph node, entirely submitted; 3 - 6 spleen nodules,
       entirely submitted; 7 - 8, spleen, away from nodules.

In the spleen described above, the pathologist found a few lumps
(nodules), representing the most important data in this gross
examination. These possibly represent the tumors of Hodgkin's
disease, subject to confirmation by the microscopic examination.
Much of the remainder of the verbage relates to "pertinent
negatives," or things that were routinely looked for but not found,
such as a rupture of the spleen capsule (suggesting an
intraoperative accident), blood clots ("thrombi") in the vessels
supplying the spleen, and evidence of an infection (in which case
the cut surface of the spleen would be soft instead of firm). In
addition, a lymph node was serendipitously found adherent to the
spleen, and this was briefly described as having a normal
appearance.

The last paragraph of the gross description gives the identifying
"codes" of the slices of the specimen submitted for microscopic
examination in cassettes. The microscope slides prepared from the
processed samples will be labeled with the same numbers as the
cassettes, and the pathologist doing the microscopic examination
can, by referring to the typed gross description, know from what
part of the specimen the tissue on the slide came.

B. THE MICROSCOPIC EXAMINATION

The microscopic description, or the "micro" is a narrative
description of the findings gained from examination of the glass
slides under the microscope. The micro is considered somewhat
"optional" in a written report. In such a case, the diagnosis (see
below) is considered to speak for itself. Here is a the microscopic
description on the report of the colon biopsy given above:

       Specimen A: The sections show a polypoid structure
       consisting of a central fibrovascular core, surrounded
       by a mantle of mucosa showing an adenomatous
       architecture with a predominantly tubular pattern. The
       tubules are lined by tall columnar epithelium showing
       nuclear pseudostratification, hyperchromasia, increased
       mitotic activity, and loss of cytoplasmic mucin. There
       in no evidence of stromal invasion.

It can be readily seen that the language of microscopy is much more
arcane than that used for gross descriptions. It is way beyond the
scope of this monograph to cover the nuances of descriptive
microscopic pathology. In general, microscopic descriptions are
communications between pathologists for referral and quality
assurances purposes.

C. THE DIAGNOSIS

This is analogous to the "bottom line" of a financial report. The
purpose of the gross examination, the processing of the tissue, and
the microscopic examination is to build a logical argument toward a
terse assessment of what significance the biopsy has in regard to
the patient's health. Here is the diagnosis for the colon biopsy,
above:

       Colon, sigmoid, endoscopic biopsy: tubular adenoma
       (adenomatous polyp)

This format is widely used, but variations occur. The first term is
the organ or tissue involved ("colon"). The second term ("sigmoid")
specifies the site in the colon from which the biopsy was obtained.
The next term ("endoscopic biopsy") denotes the type of surgical
procedure used in obtaining the biopsy. Then follows the diagnosis
proper, in this case "tubular adenoma," a common benign tumor of the
large intestine and rectum, which increases the risk for developing
colorectal cancer in the future. In this particular case, an older
synonym for tubular adenoma, "adenomatous polyp," follows in
parentheses.

GLOSSARY OF IMPORTANT DIAGNOSTIC TERMS

Finally, it may be useful to present a brief glossary of important
terms used in pathologic diagnoses. Terms in the definition that are
in ALL CAPS have their own entry.

ABSCESS

       A closed pocket containing pus. Some abscesses are easily
       diagnosed clinically, as they are painful and may "point out"
       such that pus becomes visible, but deep and chronic abscesses
       may just look like a TUMOR clinically and require biopsy to
       distinguish them from neoplasm.

ATYPICAL

       The simple, straightforward definition would be "unusual,"
       but "atypical" means much more than that. In a diagnosis, the
       use of the term atypical is a vague warning to the physician
       that the pathologist is worried about something, but not
       worried enough to say that the patient has cancer. For
       instance, lymphomas (cancers of the lymph nodes) are
       notoriously difficult to diagnose. Some lymph node biopsies
       are very disturbing but do not quite fulfil the criteria for
       cancer. Such a case may be diagnosed as "atypical lymphoid
       HYPERPLASIA." Other important atypical hyperplasias are those
       of the breast (atypical ductal hyperplasia and atypical
       lobular hyperplasia) and the lining of the uterus (atypical
       endometrial hyperplasia). Both of these conditions are
       thought to be precursor warning signs that the patient is at
       high risk of developing cancer of the respective organ
       (breast and uterus).

CARCINOMA

       A malignant NEOPLASM whose cells appear to be derived from
       EPITHELIUM. This word can be used by itself or as a suffix.
       Cancers composed of columnar epithelial cells are often
       called adenocarcinomas. Those of squamous cells are called
       squamous cell carcinomas. The type of cancer typically
       recapitulates the type of epithelium that normally lines the
       affected organ. For instance, almost all cancers of the colon
       are adenocarcinomas, and columnar epithelium is the normal
       lining of the colon. There are exceptions, however.

DYSPLASIA

       An ATYPICAL proliferation of cells. This may be loosely
       thought of as an intermediate category between HYPERPLASIA
       and NEOPLASIA. It finds its best use as a term to describe
       the phenomenon in which EPITHELIUM proliferates and develops
       the microscopic appearance of neoplastic tissue, but
       otherwise tends to "behave itself" and continues to line body
       surfaces without actually invading them, as a true malignant
       neoplasm would do. It may be convenient (but not totally
       accurate) to consider dysplasia as a "pre-cancer" or an
       incipient cancer. Probably the most commonly occurring type
       of dysplasia is that of the cervix of the uterus, where a
       progression from dysplasia to neoplasia can be clearly
       demonstrated. Other dysplasias, such as those of the breast
       and prostate, are more difficult to clearly relate to
       neoplasia at this time.

EPITHELIUM

       A specialized type of tissue that normally lines the surfaces
       and cavities of the body. There are three main types: 1)
       columnar epithelium, which lines the stomach, intestines,
       trachea and bronchi, salivary and other glands, pancreas,
       gallbladder, nasal cavity and sinuses, uterus (including
       inner cervix), Fallopian tubes, kidneys, testes, vasa
       deferentia, and other ductal structures, 2) stratified
       squamous epithelium, which lines the skin, oral cavity,
       throat, esophagus, anus, outer urethra, vagina, and outer
       cervix, and 3) transitional epithelium (urothelium), which
       lines the urine-collecting part of the kidneys, the ureters,
       bladder, and inside part of the urethra.

GRANULOMA

       A special type of INFLAMMATION characterized by accumulations
       of macrophages, some of which coalesce into "giant cells."
       Granulomatous inflammation is especially characteristic of
       tuberculosis, some deep fungal infections (like
       histoplasmosis and coccidioidomycosis), sarcoidosis (a
       disease of unknown cause), and reaction to foreign bodies.

HYPERPLASIA

       A proliferation of cells which is not NEOPLASTIC. In some
       cases, this may be a result of the body's normal reaction to
       an imbalance or other stimulus, while in other cases the
       physiologic cause of the proliferation is not apparent. An
       example of the former process is the enlargement of lymph
       nodes in the neck as a result of reaction to a bacterial
       throat infection. The lymphocytes which make up the node
       divide and proliferate, taking up more volume in the node and
       causing it to expand. An example of hyperplasia in which the
       stimulus is not known is benign prostatic hyperplasia (BPH),
       in which the prostate gland enlarges in older men for no
       known reason. While hyperplasias do not invade other organs
       or METASTASIZE to other parts of the body, they can still
       cause problems because of their local physical expansion. For
       instance, in BPH, the enlarged prostate pinches off the
       urethra and interferes with the flow of urine. If untreated,
       permanent kidney damage can result.

INFLAMMATION

       A reaction, usually mediated by the immune system, to noxious
       stimuli, manifested clinically by swelling, pain, tenderness,
       redness, heat, and/or loss of function of the affected part.
       To a pathologist, however, inflammation means the
       infiltration of certain immune system cells into the tissue
       or organ being examined. These inflammatory cells include 1)
       neutrophils, which are the white blood cells that make up pus
       and are seen in acute or early inflammations, 2) lymphocytes,
       which are typically seen in more chronic or longstanding
       inflammations, and 3) macrophages (histiocytes), which are
       also seen in chronic inflammation. Some types of inflammation
       are readily diagnosable by the primary care physician, such
       as an infected skin wound that is tender, hot, and draining
       pus. Other types of inflammation are not so readily apparent
       clinically and require biopsy to distinguish them from
       neoplasms. The suffix "-itis" is appended to a root word to
       indicate "inflammation of _____." For example, cervicitis,
       pharyngitis, gastritis, and thyroiditis are inflammations of
       the cervix, pharynx (throat), stomach, and thyroid gland,
       respectively.

LESION

       This is a vague term meaning "the thing that is wrong with
       the patient." A lesion may be a TUMOR, an area of
       INFLAMMATION, or an invisible biochemical abnormality (like
       the abnormality of the sensitivity of the body's cells to
       insulin in adult-onset diabetes).

METAPLASIA

       The phenomenon by which one type of tissue is replaced by
       another type. This often results from chronic irritation of
       an EPITHELIAL lining. A good example is the cervix, in which
       chronic irritation and INFLAMMATION causes the relatively
       delicate normal columnar epithelium to be replaced by tougher
       squamous epithelium (similar to that which normally lines the
       vagina, which is naturally "built tougher" for obvious
       reasons). This phenomenon is called "squamous metaplasia." In
       it's pure state, metaplasia is not harmful, but some
       metaplasias are markers for increased risk of more serious
       diseases. For instance, a type of intestinal metaplasia of
       the stomach (in which columnar epithelium of the intestinal
       type replaces that of the gastric type) is considered a risk
       factor for the subsequent development of cancer of the
       stomach.

METASTATIC

       Of or pertaining to METASTASIS, or the process by which
       malignant NEOPLASMS can shed individual cells, which can
       travel through the lymph vessels or blood vessels, lodge in
       some distant organ, and grow into tumors in their own right.
       There are two major routes of metastasis, 1) hematogenous, in
       which the cells travel through the blood vessels, and 2)
       lymphogenous, in which the lymphatic vessels conduct the
       cancer cells. In the case of lymphogenous metastasis, the
       metastatic tumors can grow from cancers cells entrapped in
       the lymph nodes that collect the lymph draining from the
       organ where the original cancer has developed, causing the
       nodes to enlarge. In the case of breast cancer, the axillary
       (underarm) nodes are the first to become involved. In the
       case of cancer of the larynx (voice box), the nodes on either
       side of the neck (cervical nodes) are first. Hematogenous
       metastases tend to deposit in the lungs, liver, and brain.
       Many cancers metastasize both lymphogenously and
       hematogenously. Most cancer operations attempt to remove not
       only the cancerous organ, but also the lymph nodes that drain
       that organ. Some types of cancer, especially the most common
       ones (lung, breast, colon, and prostate cancers) tend to
       metastasize to lymph nodes first. Pathologic examination of
       these nodes is important in "staging" the cancer, which gives
       the patient and the doctor some idea as to the odds of curing
       the cancer and how to best treat it. A typical diagnosis of a
       specimen of a "radical" removal of a cancer may read like,

              Breast, left, mastectomy: infiltrating ductal
              cancinoma; three of fifteen axillary nodes
              contain metastatic carcinoma.

NECROSIS

       Death of tissue. Necrosis may be seen in inflammatory
       conditions, as well as in NEOPLASMS.

NEOPLASM, or NEOPLASIA

       A "new growth" of the body's own cells, a proliferation of
       cells no longer under normal physiologic control. These may
       be "benign" or "malignant." Benign neoplasms are typically
       tumors (lumps or masses) that, if removed, never bother the
       patient again. Even if they are not removed, they are not
       capable of destroying adjacent organs or "seeding" out to
       other parts of the body. Malignant neoplasms, or "cancers,"
       are those whose natural history (i.e., behavior if untreated)
       is to cause the death of the patient. Malignancy is expressed
       by 1) local invasion, in which the neoplasm extends into
       vital organs and interferes with their function, 2)
       METASTASIS, in which cells from the tumor seed out to other
       parts of the body and then grow into tumors themselves,
       and/or 3) paraneoplastic syndromes, in which the neoplasm
       secretes metabolic poisons or inappropriately large amounts
       of hormones that cause problems with functions of various
       body systems.

-OMA

       This suffix means "tumor" or "lump." It typically, but not
       invariably, refers to a NEOPLASM ("GRANULOMA" is an
       exception). In referring to neoplasms, benign ones are
       typically referred to by a word, the prefix of which refers
       to the organ or tissue of origin, followed by the suffix
       "-oma." For example, leiomyoma, osteoma, chondroma, adenoma,
       and hemangioma, refer to benign neoplasms of smooth muscle,
       bone, cartilage, glandular tissue, and blood vessel tissue,
       respectively. The analogous terms for malignant versions of
       these neoplasms are, leiomyoSARCOMA, osteosarcoma,
       chondrosarcoma, adenoCARCINOMA, and angiosarcoma.There are
       exceptions to these vocabulary rules. For instance, hepatomas
       and melanomas are all malignant. Other tumors, such as those
       of the adrenal glands, cannot be classified into benign or
       malignant categories based on pathologic appearance. Only
       their behavior in time shows their true colors. An example is
       pheochromocytoma (a tumor of the adrenal medulla), ten per
       cent of which are malignant, but we don't know just by
       looking at the tumor if a given case will fall into that ten
       per cent.

POLYP

       A structure consisting of a rounded head attached to a
       surface by a stalk (also called a "pedicle" or "peduncle"). A
       mushroom growing from the soil is an excellent example of
       what a polyp looks like. Polyps my be HYPERPLASTIC,
       METAPLASTIC, NEOPLASTIC, INFLAMMATORY, or none of the above.
       The typical polyps removed from the colon of adults during
       colonoscopy are benign neoplasms called tubular adenomas or
       adenomatous polyps. The typical nasal polyps that develop in
       people with allergies are inflammatory. The common benign
       polyps removed from the cervix are of uncertain origin.

SARCOMA

       A malignant NEOPLASM whose cells appear to be derived from
       those other than EPITHELIUM. The connective tissues of the
       body (fibrous tissue, muscle, bone, cartilage, fat, and
       lining of joints) tend to give rise to sarcomas. In adults,
       CARCINOMAS are much more common than sarcomas. This makes
       sense, because as we age, our body linings are assaulted by
       one noxious substance after the other. So it is no surprise
       that those epithelial cells on the forefront of our battle
       with the environment are the first to lose control of their
       growth and development. In children, sarcomas make up a
       greater proportion of cancers. While the connective tissues
       of adults are rather stable and protected from environmental
       assault, those of children are still growing and developing,
       the cells dividing, raising the likelihood that something
       will go haywire and cause a cell to lose control over its
       growth.

SUPPURATION, SUPPURATIVE INFLAMMATION

       A type of acute INFLAMMATION characterized by infiltration of
       neutrophils at the microscopic level and formation of pus at
       the gross level. ABSCESS is special type of suppurative
       inflammation.

TUMOR

       A mass or lump that can be felt with the hand or seen with
       the naked eye. This may be a NEOPLASM, HYPERPLASIA,
       distention, swelling, or anything that causes a local
       increase in volume. The thing to remember is that not all
       tumors are cancers, and not all cancers are tumors.

Note: Please send all constructive comments regarding this FAQ to Ed
Uthman, MD ([e-mail]).

This article is provided as is without any express or implied
warranties. While every effort has been taken to ensure the accuracy
of the information, the author assumes no responsibility for errors
or omissions, or for damages resulting from use of the information
herein.

Copyright (c) 1994-96, Edward O. Uthman. This material may be
reformatted and/or freely distributed via online services or other
media, as long as it is not substantively altered. Authors,
educators, and others are welcome to use any ideas presented herein,
but I would ask for acknowledgment in any published work derived
therefrom.

version 1.2U, 11/12/97