Kimitaka Suzuki

Prevention of local recurrence by extended lymphadenectomy for rectal cancer

This study was undertaken to determine if the degree of lymphadenectomy correlates with the prevention of local recurrence. The authors retrospectively reviewed the clinical data of 269 patients who underwent curative surgery for rectal cancer. The study was divided into three periods based on the method of lymphadenectomy as follows: period I (1963–1979) when extended lymphadenectomy was not performed; period II (1980–1985) when this was partially done with no attempt to dissect the obturator and proximal middle rectal lymph nodes; and period III (1986–1990) when this was completely performed for patients with appropriate indications. The local recurrence rates were 21%, 10%, and 8% for Periods I, II, and III, respectively (P<0.05). The incidence of local recurrence tended to be greater in period I versus periods II and III according to type of operation, location, and stage of the primary tumors. The local recurrence rates arising from lateral node metastases were 11%, 4%, and 2% for periods I, II, and III, respectively (P<0.05), while the incidence related to an insufficient surgical margin was approximately 5% throughout the three periods. We thus conclude that the degree of lymphadenectomy is a major determinant of local recurrence following a curative operation for rectal cancer.

DNA ploidy pattern of flat adenomas of the large bowel

In an attempt to clarify the nature of “flat adenomas,” DNA content was measured by means of microspectrophotometry. Thirty-nine flat adenomas (FA), 13 with mild, 22 with moderate, and 4 with severe atypia, were collected for this study. In FA, diploidy (D), polyploidy (P), and aneuploidy (A) were found 100, 0, and 0 percent in mild atypia, 41.9, 4.5, and 54.5 percent in moderate atypia, and 0, 0, and 100 percent in severe atypia, respectively. It is assumed that FA have a much higher malignancy potential than previously expected since, histologically, benign-appearing FA with moderate atypia have already contained malignant DNA patterns. In particular, those more than 5 mm in diameter show aneuploidy in 80 percent. These data suggest that FA with moderate atypia play an important role in the pathogenesis of small colonic carcinomas.

Steroid complications and surgery in intractable ulcerative colitis

Abstract: The major operative indication for ulcerative colitis is intractability. Although steroid side effects appear to be closely associated with surgical indications for intractable ulcerative colitis, this relationship has yet to be analyzed in detail. To elucidate this relationship, we investigated 39 surgical patients with intractable ulcerative colitis, as defined by the Research Committee for Intractable Diseases of the Ministry of Health and welfare of Japan, and 66 conservatively treated patients with ulcerative colitis, of whom 6 had intractable disease. All patients with major steroid side effects and 17/24 (71%) patients with minor side effects underwent surgery. The median number of admissions was higher in patients with major side effects than in those with less severe or no side effects in the operative series, while this value was lower in the non-operative series than in the operative series. This tendency was similar for the total duration of hospitalization and the number of relapses. In the operative series, markedly higher steroid doses were administered to patients with side effects than to those without, and lower doses were given in the non-operative series. On multivariate regression analysis, the presence of steroid side effects, disease extent, and disease duration were significantly associated with surgery. Patients without side effects had a higher postoperative complication rate than those with minor side effects. We conclude that major side effects are a surgical indication for patients with intractable ulcerative colitis, and that even minor side effects should be taken as a surgical indication in view of the patients quality of life.

DNA ploidy pattern in rectal carcinoid tumors.

The nuclear DNA pattern of 22 rectal carcinoids was determined by cytophotometry of paraffin embedded tissues. The results were compared with clinical as well as histopathologic features of the tumor. Three of the carcinoids with synchronous or metachronous metastasis had aneuploid DNA pattern, whereas 19 tumors with no metastasis showed diploid DNA pattern. No other single clinical or pathologic feature of the tumor could predict more accurately the malignant potential and the subsequent course of the rectal carcinoid. It is concluded that DNA aneuploidy in rectal carcinoid tumors is not so rare as indicated by earlier studies and that it is a factor of significant prognostic value.

Chronic Active Disease Reflects Cancer Risk in Ulcerative Colitis

There is an increased risk of developing colorectal neoplasia in ulcerative colitis (UC) and surveillance colonoscopy is recommended for early detection. We investigated the precise features of UC retrospectively to identify a subgroup with longstanding extensive UC at increased risk of neoplasia. From 1985 to August 1997, we experienced eight UC patients with colorectal cancer and eight with definite dysplasia. All 16 had extensive disease of seven years or more in duration. During the same period, 61 of 334 UC patients without colorectal neoplasia were available for detailed study, allowing evaluation of non‐surgical patients with extensive colitis of seven years or more in duration. Basic clinical factors including family history of cancer, expressions of disease activity and durations of pharmacotherapy were investigated. Univariate analysis revealed four significant factors: intractability (P=0.001), periods of inflammation persisting for 3 months or more (P<0.01) and total durations of diarrhea (P<0.01) and hematochezia (P<0.05). The number of admissions and the duration of systemic steroid administration were higher in the neoplasia group but without statistical significance. Multivariate analysis revealed two significant factors: duration of diarrhea (P<0.001) and age at onset (P<0.01). Chronic active disease is a risk factor for colorectal cancer or dysplasia in extensive and longstanding UC.

A microspectrophotometric study of DNA ploidy patterns of colorectal adenomas.

SummaryEighty-four adenomas (31 mild, 25 moderate, 28 severe atypia), 32 invasive carcinomas and 15 samples of normal mucosa were collected form polypectomy and surgically resected specimens, and their DNA ploidy patterns were examined by microspectrophotometry. The frequency of polyploidy and aneuploidy were 7% and 0% in normal mucosa, 13% and 0% in mild atypia, 20% and 44% in moderate atypia, 32% and 22% in severe atypia and 31% and 53% in invasive carcinomas, respectively. Furthermore, these abnormal ploidy patterns were found frequently in moderate atypia accompanying severe atypia and mild atypia accompanying moderate atypia. These findings suggest that adenomas with moderate atypia might be the early stage of histologically overt cancer. The thin-section method (4 μm or 7μm) was useful for measuring regional DNA ploidy patterns of colorectal adenoma.

The Role of Lateral Lymphnode Dissection in the Prevention of Recurrence for Rectal Cancer

In an attempt to clarify the role of lateral node dissection in preventing the local recurrence of rectal cancer, 203 patients undergoing surgery for advanced lower rectal cancer in our surgical department from 1963 to 1991 were studied retrospectively. The incidence of lateral lymphnode metastases was higher in patients with tumors invading beyond the subserosa and a higher recurrence rate was observed in patients with lymphnode metastasis diagnosed at or before operation. Lymphnode metastases were found in 18.2% of the patients undergoing lateral node dissection, and surgery was succeeded in 66.7% of these patients, although 50% of the cases had tumors invading beyond the subserosal layer. The recurrence rate was 33.3%. We concluded that the lateral node dissection plays an important role in preventing local recurrence of rectal cancer, and should be indicated for all patients with either lymphnode metastases or tumors invading beyond the subserosal layer.

Abstracts of selected papers presented at the 34th annual meeting of the japanese society of gastroenterology

M E E T I N G O F T H E J A P A N E S E S O C I E T Y O F G A S T R O E N T E R O L O G Y October 12-14, 1992-Utsunomiya, Japan Chairman: Takashi Harada, M.D.

Abstracts of selected papers presented at the 77th General Meeting of the Japanese Society of Gastroenterology

M E E T I N G OF T H E J A P A N E S E S O C I E T Y OF G A S T R O E N T E R O L O G Y March 28-30, 1991-Tokyo, Japan Chairman: Yutaka MATSUO, M.D.