Tatsuo Oshiro

Clinical significance of occult micrometastasis in lymph nodes from patients with early gastric cancer who died of recurrence

BACKGROUND Even after curative resection of an early gastric cancer, some patients die of a recurrence. It is our view that patients with early gastric cancer who died of their disease had occult micrometastases in perigastric lymph nodes at the time of the original diagnosis. In an attempt to identify these micrometastases, lymph nodes dissected from early gastric cancer lesions were stained after operation with monoclonal antibody against cytokeratin, an essential constituent of the cytoskeleton of epithelial cells. METHODS The 420 dissected lymph nodes from 34 patients with node-negative early gastric cancer who died of a recurrence were examined for the presence of tumor cells. We used immunocytochemical techniques and an antiserum to epithelial membrane antigen. The monoclonal antibody CAM 5.2 recognizes cytokeratin polypeptides (human cytokeratin numbers 8 and 18) commonly present in epithelial cells. Clinicopathologic characteristics and prognosis were determined for patients with cytokeratin-positive cells in the lymph nodes. RESULTS. Of 420 lymph nodes, 15 (3.6%) nodes and 23.5% (8 of 34) of the patients presented with cytokeratin-positive cells at the time of primary operation. The presence of cytokeratin positivity was not related to various clinicopathologic factors. The histologic stage of eight cytokeratin-positive cases was upstaged by the group of cytokeratin-positive lymph nodes from stage I to three of stage II, four of stage III, and one of stage IV, hematogenous recurrences were common, and the prognosis was poorer. CONCLUSIONS Immunohistochemical techniques aid in identifying micrometastatic disease in lymph nodes missed in routine hematoxylin-eosin staining. Cytokeratin staining of the dissected lymph nodes is recommended to precisely determine tumor stage and prognosis for patients with early gastric cancer.

Tumor size as a simple prognostic indicator for gastric carcinoma

AbstractBackground: Tumor size can be measured easily before or during operation with no special tools, but its prognostic use in patients with gastric carcinoma is still unclear. Methods: Clinicopathologic data of 479 patients who underwent curative operation for gastric carcinoma were studied. The relationship between tumor size and survival of patients was investigated. Results: The patients were divided into three groups: 182 with tumors measuring <4 cm (group I), 252 with tumors of 4–10 cm (group II), and 45 with tumors of ⩾10 cm (group III). The 10-year survival rates for group I, II, and III patients were 92%, 66%, and 33%, respectively (p<0.01), and the three groups were significantly different with regard to depth of invasion (p<0.01), number and level of lymph node metastasis (p<0.01), and stage of disease (p<0.01). Multivariate analysis indicated that tumor size independently influenced the survival of patients. Conclusions: Tumor size clinically serves as a simple predictor of tumor progression and survival of patients in gastric carcinoma.

Age-related characteristics of gastric carcinoma in young and elderly patients

The clinicopathologic features of young and elderly patients with gastric carcinoma have been analyzed.

Lymphatic invasion and potential for tumor growth and metastasis in patients with gastric cancer

BACKGROUND Lymph node metastasis is a risk factor for the occurrence of peritoneal dissemination and liver metastasis in patients with gastric cancer. METHODS We analyzed data on 324 patients with serosally invasive gastric cancer with respect to the relation between lymphatic invasion and potential for tumor growth and metastasis. All these patients were curatively treated in the Department of Surgery II, Kyushu University. RESULTS Lymphatic invasion was evident in 214 patients, in whom vascular invasion was more frequent and the rate of lymph node metastasis was higher compared with patients with no lymphatic invasion. There was no difference in tumor size. The type of recurrence varied, and the prognosis was poor in patients with lymphatic invasion. The DNA ploidy pattern was higher, and the levels of proliferating cell nuclear antigen labeling and argyrophilic nucleolar organizer regions count were significantly higher in tumor tissues with lymphatic invasion than in those without invasion. CONCLUSIONS Gastric cancers with characteristics of lymphatic invasion have higher proliferating activities, and metastases to distant organs are likely.

Prediction of early and late recurrence after curative resection for gastric carcinoma

Although several prognostic factors for patients with gastric carcinoma have been demonstrated, those predictive of early and late recurrences after surgery are still unclear.

A simple classification of lymph node level in gastric carcinoma

BACKGROUND Because insufficient lymph node examination can cause erroneous listing of earlier-nodal-stage gastric carcinoma (stage migration phenomenon), surgical results must be evaluated based on a highly accurate examination of the dissected lymph nodes. To establish a simple and useful classification of lymph node level, we analyzed the frequency and distribution of lymph node metastasis by using curatively treated node-positive gastric carcinoma. PATIENTS AND METHODS Various clinicopathologic data were analyzed with reference to the degree of lymph node metastasis by using 240 patients with curatively resected node-positive gastric carcinoma. The cases were divided into the following three groups: 142 with positive level I (perigastric) nodes, 71 with positive level II (intermediate) nodes, and 27 with positive level III (distant) nodes, irrespective of the location of tumors. RESULTS The level of lymph node metastasis clearly correlated with the survival of patients, with the 5-year survival rates for level I, II, and III cases being 67%, 35%, and 26%, respectively (P < 0.01). The degree of lymph node metastasis was determined by the number of positive nodes (P < 0.01), the depth of invasion (P < 0.01), the size of tumors (P < 0.01), and the location of tumors (P < 0.05). CONCLUSION This simple classification of lymph node level (level I, II, and III) is useful for the evaluation and prediction of surgical results in gastric carcinoma.

Effectiveness of extended lymphadenectomy in noncurative gastrectomy

PURPOSE We examined the efficacy of extended lymph node dissection for prolonging survival in macroscopically or histologically proven incurable gastric cancer. PATIENTS AND METHODS We analyzed clinico-pathologic data on 119 patients with serosally invasive gastric cancer who underwent noncurative gastrectomy, with respect to the relation between the extent of lymphadenectomy and survival benefit. RESULTS The 5-year survival rate was significantly higher among patients treated with extensive lymphadenectomy (R2/3) compared to simple gastrectomy (R1). Extensive lymphadenectomy significantly prolonged survival time even after noncurative gastrectomy in cases where there was no evidence of hepatic metastasis, peritoneal seeding, or extensive nodal metastasis beyond the tertiary lymph node, and regardless of the extent of direct invasion to adjacent organs. CONCLUSIONS Gastrectomy combined with extended lymphadenectomy and/or resection of adjacent organs is recommended for gastric cancer patients without distant metastasis, even when the operation is histologically noncurative. Gastrectomy and perioperative intensive chemotherapy are called for when patients have distant metastasis.

Analysis of 390 Patients Surviving 10 Years or Longer after Curative Resection for Gastric Cancer

We analyzed clinicopathological features and prognosis of 390 Japanese patients with gastric cancer who survived 10 years or longer after curative resection. All of the patients were treated in our clinics. One hundred and ninety-one of these patients had early gastric cancer and the other 199 had advanced gastric cancer. The mean age was 53.5 years and the male to female ratio was 2:1. The upper one-third of the stomach was less commonly involved and a partial gastrectomy was most often done. Lymph node metastasis was present in 28.7% and extensive lymph node dissection (R2 or R3) was done in 92.5% of the cases. Nine patients died with a recurrence of gastric cancer and 20 patients died with a malignancy in other organs. Curative resection with extensive lymph node dissection and, when required, combined resection of the neighboring organs does improve the survival rate for patients with either early or advanced gastric cancer. An annual follow-up examination to rule out recurrences or malignancies in other organs is to be recommended.

Effect of gastrectomy on the pharmacokinetics of tegafur, uracil, and 5-fluorouracil after oral administration of a 1: 4 tegafur and uracil combination

The effects of gastrectomy on the pharmacokinetics of UFT, a combined oral preparation of 1-(2-tetrahydrofuryl)-5-fluorouracil (tegafur) and uracil at a molar ratio of 1∶4, were examined in 26 patients with macroscopic State I gastric cancer. In all, 200 mg UFT (in terms of tegafur) was given to 17 patients who underwent partial gastrectomy (9 cases of Billroth I reconstruction, 8 cases of Billroth II reconstruction) and to 9 patients who underwent total gastrectomy with modified Roux-en-Y reconstruction. Before the operation, the area under the curve (AUC) for tegafur, uracil, and 5-fluorouracil (5-FU) was 79.28±26.88, 4.41±1.78, and 0.51±0.20 μg h ml−1, respectively. Partial (Billroth I and II) and total gastrectomy did not alter the AUC of tegafur, and partial gastrectomy using the Billroth I and II methods decreased the AUCs of uracil and 5-FU during the first 2 weeks postoperation. However, plasma levels of uracil and 5-FU reverted to preoperative values at 3 months postsurgery. Our findings show that when UFT is prescribed for patients treated in the early postoperative period following partial gastrectomy for cancer, dose increases and the timing of administration should be given close attention.

Clinical manifestations in patients with hereditary nonpolyposis colorectal cancer

The clinical manifestations of 1,042 Japanese patients with nonpolyposis colorectal cancer who underwent a resection between 1972 and 1992 at the National Kyushu Cancer Center were examined. Hereditary nonpolyposis colorectal cancer (HNPCC) was found in 39 (3.7%) patients. Some characteristic findings in HNPCC cases included early age of onset, a preponderance of right colon cancers, an increased frequency of colorectal cancers, and a favorable survival. Metachronous (postoperative) colorectal cancers developed significantly more often in cases with HNPCC than in those without (12.8% vs. 1.8%, P = 0.0001). Metachronous (postoperative) extracolonic cancers tended to develop more often in cases with HNPCC than in those without (10.2% vs. 3.5%, P = 0.053). In cases with HNPCC, the mean interval between the initial surgery and the diagnosis of the second cancer was 61 months (range; 12–153 months). These findings thus indicate the importance of routine and long‐term follow‐up to identify any second lesions, especially in patients with HNPCC.