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The term pathology, derived from the greek pathos - suffering and logos - discourse, refers to the scientific basis of medicine. It is a fundamental discipline in the training of health personnel and serves as an anchor for medical education in general. Pathology concerns itself with the causes of disease, the mechanisms involved, the course of disease and the structural and functional changes in organs, tissue and cells that ensue in the various disease conditions.
Over time, this knowledge has led to physicians with special training in pathology being recognized as specialists in the interpretation of changes and abnormalities in diseased cells, tissue and organs. Currently, the work is primarily concerned with pathological anatomy. The changes may be visible to the naked eye, but microscopy plays a crucial role. Pathologists endeavour to elucidate the nature of the patients problems and make a diagnose based upon the disease changes observed.
It is the pathologists who diagnose cancer. We determine, for example, whether there are pre-cancerous changes, obvious current cancer, the type of cancer, whether it is fast growing and has spread to other parts of the body. Many of the biopsies sent to us from patients relate to this problem area and the number of such biopsies grows yearly. In addition to rendering a diagnosis, reports often include explanatory comments and advice to the physician who has submitted the the biopsy. The diagnosis gives an indication of the prognosis (outlook) of the disease in question allowing the attending physician to carry out appropriate studies and institute treatment of the patient affected. We provide an essential service for the attending physicians and close cooperation with other physicians is therefore of the utmost importance.
The pathologists main working tool is the microscope by means of which small tissue samples or large operation specimens / biopsies and cell preparations / cytology can be be studied. These may be taken from both healthy persons /screening as in preventative medicine and from ill persons.
Tissue that the clinician has removed from the patient is usually placed in a fixing fluid (formalin). Small tissue samples or large organs are examined and an appropriate number of representative tissue samples are taken by means of a scalpel or similar instrument and placed in capsules. The biopsy material is passed through a number of different fluids before it is finally embedded in paraffin wax. The tissue material is then hard enough for thin sections (typically about 5 microns thick) to be cut, using a special microtome knife. These sections are further treated with various stains and when the specimen is viewed under the microscope, its various cellular components appear often strikingly different from one another, exhibiting an impressive range of colour and tones. These stains are helpful in that they can be highly specific both for the different varieties of normal cells and tissues, but also in highlighting abnormalities. In his/her diagnostic work, the pathologist may make use of many special stains. Close cooperation with laboratory technologists is important in this connection.
Cellular material taken from the patient is most often received as smears on object glasses. Prior screening of cytology specimens (for example in mass screening for cervical cancer) is carried out by specially trained cytotechnologists before the pathologist reviews the material and makes a diagnosis. Much of the work and findings is documented in the form of written reports.
The work in a pathology department differs materially from that in other areas of laboratory medicine in that it is personnel-based. This means that the possibilities for automation or machine-generated diagnostics are few. The nature of the work more closely resembles that of an X-Ray department where specially trained physicians also evaluate the changes seen on film.
Cells and tissue samples, like persons, are highly individual. No two are alike. There are many types of cancer, differentiation and stages in different organs and one frequently finds the boundaries to be unclear. This complexity also applies to other disease groups.
In many cases, the tissue or cellular material we receive from the diseased area is rather meagre. Under such circumstances evaluation and diagnosis is involved or difficult. Adequate clinical information on the patient and the material submitted is essential. We must, moreover, have at our disposal considerable sources for literature reference and searches so that our knowledge is continually updated. The department maintains a large and varied store of tissue and cellular material. Any earlier material from the patient, must be available for review in conjunction with the current specimen. All tissue sections, cellular preparations and tissue samples are stored for future reference. No pathologist is able, however, to master the entire field of pathology. Much of the diagnosis is based upon experience and from time to time it is important that several pathologists express their opinion of the same changes observed in a particular case. Slides may be sent to other pathologists in Norway for special assessment. On rare occasions, the material may be sent to pathologists abroad when they are considered to be most experienced in the special field in question. Evaluation may be so difficult that pathologists render somewhat different diagnoses and one cannot decide who is right and whether any of them actually has the correct diagnosis. In such cases only time will reveal the outcome. Unfortunately, one has to accept this, since there is no other better diagnostic method is available. In practice, even where an exact diagnosis has not been made, the insight provided provides a basis for adequate patient control and treatment.
In order to facilitate discussion of professional matters a number of pathology departments have begun using telepathology where the departments and microscopes are coupled together audiovisually. This represents a rapidly developing subgroup of telemedicine that needs to be promoted and expanded in the coming years.
Recently, many new methods of investigation have become available that are able to provide the pathologists with additional information and thus help in assessment and the final diagnostic goal. Examples are immunochemistry, gene technology, molecular pathology and advanced counting and measuring methods /flow cytometry. All of these, however, are limited in scope and there are, for instance, no technical methods that can unerringly distinguish basically normal cells from cells or tissue from cancer or precancerous conditions. Such assessments are still based upon good, solid professional judgement.
Frozen (Cryostatic) sections
When routine diagnostic procedures are employed it takes several days before the pathologist reaches a diagnosis and gives his/ her assessment of the case. By making use of so-called frozen sections tissue removed during operations in progress may be frozen, cut into thin sections and stained. This method is much utilized where cancer is suspected, for example in questions related to breast cancer. After appraisal by the pathologist, the answer is transmitted directly to the operating surgeon (usually by intercom). This is followed up by written confirmation. The surgeon concerned thus has, at his/ her disposal, information as to what needs to be done, for example remove the breast. This ready availability of rapidly transmitted information and the fact that the patient avoids the need for further operations, means that the method is an excellent one, but from the pathologists point of view, evaluation of such biopsies is more difficult than is the case with routine procedures, due to the fact that the technical standard of the microscopic sections is poorer.
Fine Needle Aspiration Cytology
There exists a form of investigation that is very quick, patient friendly, cheap and suitable for cancer diagnostic. This is fine needle aspiration cytology. The attending physician or pathologist inserts a syringe needle into the tissue from which material is required for diagnosis, for example a tumour. The needle can also be guided using fluoroscopic (real-time X-Ray) control or ultrasound. Cell material is then withdrawn for further processing and microscopic study. More and more sites on the body are becoming accessible to this approach. The method is being much utilized in cases where malignancy is suspected and is an important tool in screening for breast cancer. It is often used in conjunction with mammography.
It has become apparent that an optimal result with the acquisition of good diagnostic material is best obtained when the pathologist takes the sample from the patient (usually at an out-patient clinic, set-up expressly for this purpose). This is the case in many hospitals, but unfortunately not in our department owing to a shortage of staff pathologists. The diagnostic interpretation of aspiration biopsies demands special expertise on the part of the pathologist.
Autopsy (Post Mortem) (= obduction) in English, writer Ed Uthman, M.D, (U.S.A.)
Because of the shortage of pathologists and an excessive workload, our pathology department at the present time concentrates its activities mainly on diagnostic investigation of material removed from living patients. In Norway, autopsy activity has been seriously scaled back and the number of autopsies has decreased markedly in recent years. In 1993, only 14% of the deaths were autopsied (as opposed to the recommended number of 40%). This is somewhat of a paradox in view of the current emphasis on quality control. Autopsies constitute an excellent mode of quality control of the health sectors medical diagnostics and treatment. The cut-back in the number of autopsies in Norway means, in practice, that in the majority of cases, one is uncertain of the cause of death and the countrys mortality statistics are therefore unreliable. In light of the recent promotion of quality in medical care this is a disturbing tendency. It is of interest to note that studies in several countries have shown that a number, varying from a few percent to 60 % of clinical diagnoses are significantly incorrect, to a greater or lesser degree. By and large, clinical diagnoses differ significantly from autopsy findings in about 20% of cases. This applies, for example, to many cases of lung and heart infarcts. Many cases of cancer are not found clinically or registered. In so-called open and shut clinical cases, the pathologist frequently demonstrates surprising or overlooked findings at the time of autopsy. Low autopsy frequency also impinges on medical education. Their value in teaching programmes is lost and the next of kin are deprived of the information they seek. The number of medicolegal autopsies has, unfortunately, also been reduced.
The discipline of pathology continues to develop and grow. Clinicians and the fact that new methods of clinical investigation and operation are continually being introduced call for a more comprehensive, detailed and itemized diagnostic approach, and greater precision in the diagnosis. Staff at all levels in the pathology laboratory must contribute by ensuring the greatest possible accuracy. The staff must be well-trained and educated, able to assist the pathologist in achieving a satisfactory final diagnosis.
Department of Pathology, Vestfold Sentralsykehus, Tønsberg, Norway:
The only centre in Vestfold County offering an anatomical pathology service. Started in 1980 with the goal of covering the entire needs of Vestfold county. New location on the top floor of the hospital laboratory block. Modern and well-equipped. Positions authorized (pathologists, laboratory technologists, office personnel, autopsy assistant).
In Norway: Approximately 22 centres provide pathology service, including private laboratories.
There is a current shortage of pathologists.
This Home Page was first created 13. August 1996
Copyright © 1996 Birger Fr. Motzfeldt Laane,
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