Diagnostic Pathology Division
Introduction
The Diagnostic Pathology Division
belongs to the Clinical Laboratory Division. It is responsible for pathologic
diagnosis of biopsy, surgical, and cytological 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 1999, final pathology diagnoses have become
accessible through the MIRACLE system the next day following electronic sign-out
by pathologists.
Routine Activities
The division has fifteen pathologists
(ten of them are collaborating staff from the National Cancer Center Research
Institute), including eleven board-certified staff pathologists and two 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.
1. Surgical pathology
About 10,600 biopsy materials,
including 1,023 intraoperative frozen sections and 3,000 surgically resected
materials, were examined in 1999. 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 1999, requests for intraoperative
examination of surgical margins of resected breast cancer and biopsy diagnosis
of graft-versus-host disease increased markedly.
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, and is increasing in frequency
annually. 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 second pathologist perform table discussion on gross
findings. Selected cases are further discussed at an autopsy conference after
the whole examination.
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 over 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 1999, including some lectures concerning the pathology
of graft-versus-host disease and the classification of lung tumors. An autopsy
conference is held once a month.
Research Activities
1. We reported that non-polyploid growth (NPG) type
early colorectal cancer is morphologically superficial, with significantly
smaller lesions that showed deeper infiltration than the lesions of the polyploid
growth (PG) type of cancer. Moreover, the NPG type histol-ogically showed
adenocarcinoma with high-grade atypia and without coexistence of an adenomatous
component (de novo cancer) (Kurisu, Shimoda).
2. Differentiated adenocarcinomas of the stomach
can be classified into one of two major types, gastric or intestinal, by immuno
and mucin histochemical analysis. Most of the minute cancers of the stomach
are differentiated adenocarcinomas with gastric phenotypic expression, and
these cancers are histologically derived from the propria gastric mucosa without
intestinal metaplasia (Egashira, Shimoda).
3. The clinicopathologic features and problems in
diagnosis of the pancreatic neoplasm with abundant mucus production were analyzed,
with a focus on the distinction between intraductal papillary-mucinous tumors
and mucinous cystic tumors (Fukushima et al.).
4. Several important case reports were published.
Among them, we reported a case of synovial sarcoma, histologically mimicking
Ewing's sarcoma in metastatic site. In this report, we discussed histol-ogical
and immunohistochemical pitfalls in the diagnosis of poorly differentiated
sarcomas, and the importance of auxiliary molecular analysis (Masui, Matsuno
et al.).
5. In collaboration with the clinical groups, members
of the division contributed to the pathology review activities in clinical
oncology studies. Through these activities, the problems in interobserver
agreement were discussed in breast cancer pathology (Tsuda et al.).
|
Number
of Cases Examined |
||
|
1998 |
1999 |
|
|
Biopsy
and surgical materials |
11,714 |
13,580 |
|
Frozen sections |
800 |
1,023 |
|
Cytological
materials |
13,043 |
12,651 |
|
Intraoperative cytology |
580 |
772 |
|
Autopsy |
109 |
74 |
(T.
SHIMODA)
