Diagnostic Pathology
Division
Introduction
The Diagnostic Pathology Division
belongs to the Clinical Laboratory Division. It is responsible for pathologic
diagnosis of biopsy, surgical, and cyto-logical materials and for diagnosing
and reporting autopsy findings. Maintenance of the pathology resource of the
National Cancer Center Hospital in a good (safe and effective) condition is
another important task.
The close and efficient interrelationship between histopathology and cytopathology within the division works very well to ensure a high quality of pathologic diagnosis. The customized computer-assisted pathology system promotes this interrelationship through easy cross-referencing of each diagnosis. Since January 2000, final pathological diagnosis and description have become accessible through the MIRACLE system the next day following electronic sign-out by pathologists.
Routine Activities
The division has 15 pathologists (nine of them are collaborating staff from the National Cancer Center Research Institute), including 11 board-certified staff pathologists and four pathology residents. Seven of the pathologists take part in cytopathology as well, contributing as both general pathologists and as experts in specific organ tumor pathology. In order to complement morphological examination, auxiliary diagnostic tests such as immunostaining, electron microscopy, and PCR-based molecular analysis are applied to selected cases. To facilitate the application of ancillary diagnostic studies, frozen tumor tissue is now systematically collected in collaboration with the Pathology Division, Research Institute.
1. Surgical pathology
About 11,700 biopsy materials, including 1,280 intraoperative frozen sections and 3,300 surgically resected materials, were examined in 2000. Organ expert pathologists, followed by confirmation by another general pathologist on service, make all the histopathological diagnoses. Intraoperative diagnosis provides surgeons with critical information to assist them in performing successful surgery. Regional lymph nodes and surgical margins of resected organs are most frequently submitted. Pathology residents on call primarily participate in making frozen section diagnosis, which is confirmed by staff pathologists. In 2000, requests for intraoperative examination of surgical margins of resected breast cancer, biopsy diagnosis of graft-versus-host disease increased and 250 EMR (endoscopic mucosal resection) materials of gastrointestinal tract were closely examined. Frozen tissue storage system was established.
2. Cytopathology
Approximately 40% of the materials submitted for cytopathology are gynecologic, 20% are urologic, and another 20% are from the respiratory system. For quality assurance, a double screening system, in which at least two cytotechnologists examine each slide, has been established. Thereafter, cyto-pathologists sign out each case after a mutual double confirmation in most cases. Intraoperative diagnosis contributes to clinical decisions concerning surgical procedures. Specimens most frequently submitted are pleural, ascitic, and body-cavity lavage fluids.
3. Autopsies
Autopsies are performed primarily to evaluate the actual extent of tumor spread, the immediate cause of death, or the effects of therapy. Immediately after each autopsy, the prosecutor, the physician, and a supervising pathologist perform table discussion on gross findings. Selected cases are further discussed at an autopsy conference after the whole examination. The number of autopsy cases has been decreasing over the past years.
4. Conferences
Besides conferences to discuss each organ pathology with physicians, we have pathology case conferences or mini-seminars weekly to discuss a variety of cases as a quality assurance activity. The members of the Pathology Laboratory, National Cancer Center Hospital East, join most of the case conferences through the TV conference system. Working cooperatively with the Cancer Information and Epidemiology Division of the National Cancer Research Institute, we had five multi-institutional pathology TV conferences in 2000. An autopsy conference is held once a month.
Research Activities
1. We reported that lymphatic permeation is a good predictor of lymph node metastasis from squamous cell carcinoma of the esophagus and the histological grades are independent prognostic factors. Vessel permeation, vertical tumor invasion depth in the submucosal layer and histological grade were found to be important factors for identifying patients who did not require additional surgical treatment after endoscopic mucosal resection of superficial esophageal cancer (Cancer).
2. We reported that ductal involvement as a pathway of tumor spread to the deeper layers has little significance in squamous cell carcinoma of the esophagus, and that mucosal carcinomas with ductal involvement that extends to the submucosa should not be classified as submucosal invasive cancer (Cancer).
3. The consensus classification of gastrointestinal epithelial neoplasia by worldwide pathologists was reported (Gut).
4. We have recently proposed a grading system for adult soft-tissue sarcoma based on three criteria: tumor differentiation, necrosis and MIB-1 score. This system was, by multivariate analysis, the most significant independent prognostic factor. We also found that this grading system was associated with overall survival of patients with dedifferentiated liposarcoma of retroperitoneum and mesentery.
5. We reported orthodox histochemistry,
Perodic acid-Schiff and high iron diamin alcian blue, is very useful for the
diagnosis of minimal deviation adeno-carcinoma (MDA) of the uterine cervix.
MDA cells produce PAS positive neutral mucin, and show negative for alcian
blue positive acid mucin. (Am J Surg Pathol).
|
Number
of Cases Examined |
|
|
|
|
|
1998 |
1999 |
2000 |
|
Biopsy and surgical materials |
11,714 |
13,580 |
14,973 |
|
Frozen sections |
800 |
1,023 |
1,280 |
|
Cytological materials |
13,043 |
12,651 |
12,911 |
|
Intraoperative cytology |
580 |
772 |
756 |
|
Autopsy |
109 |
74 |
66 |
(T.
SHIMODA)
