Postoperative chemotherapy for patients with advanced gastric cancer

Vascular invasion and potential for tumor angiogenesis and metastasis in gastric carcinoma

BACKGROUND

Hematogenous metastasis occurs when cancer cells released from the primary site enter blood vessels and are transported to distant organs, where they attach and proliferate. Angiogenesis is essential for tumor growth and metastasis and depends on the production of angiogenic factors by tumor cells.

METHODS

We analyzed data on 1184 Japanese adult men and women with gastric cancer with respect to the relation between vascular invasion and the potential for tumor angiogenesis and metastasis. All these patients were treated from 1976 to 1995 in the Department of Surgery II, Kyushu University. In 300 patients, the expression of vascular endothelial growth factor (VEGF) and p53 protein in tumor tissues was examined by using an immunohistochemical staining method or Northern blotting or both. Intratumoral microvessels were stained with anti-CD31 monoclonal antibody.

RESULTS

Vascular invasion was evident in 254 patients (21.5%), and in these patients lymphatic invasion was more frequent and the rate of lymph node metastasis was higher in relation to the extent of vascular invasion. The positive findings were directly related to the depth of invasion and the presence of lymph node and liver metastasis. Tumor invasive and metastatic rates increased in relation to the extent of vascular invasion. Expressions of VEGF and p53 protein were higher and microvessel density was more prominent in tumor tissues in relation to the extent of vascular invasion. A close relation between VEGF and p53 protein expressions was also noted in tumors that showed vascular invasion. The expression of VEGF is one of the independent risk factors for vascular invasion. The postoperative outcome was poorer in patients with vascular invasion in relation to the extent of vascular invasion.

CONCLUSIONS

Our findings show that gastric cancers with characteristics of vascular invasion have greater intratumoral angiogenesis and that VEGF and p53 overexpression is associated with intratumoral angiogenesis and metastases to distant organs.

Surgical treatment and outcome for node-negative gastric cancer

BACKGROUND

The clinicopathologic characteristics and prognosis for patients with node-negative gastric cancer have heretofore remained to be determined.

METHODS

We analyzed data on 730 of our patients with node-negative gastric cancer who underwent curative gastric resection in the Department of Surgery II, Kyushu University Hospital, between 1965 and 1990, with reference to prognostic factors. The presence of lymph node metastasis was determined by means of routine hematoxylin-eosin staining of excised tissues.

RESULTS

The 5-year survival rate was 91.7% and the 10-year rate was 88.5%; thus the prognosis was good for patients with node-negative gastric cancer. When the prognosis was analyzed by stratification of each clinicopathologic factor, the survival time was shorter for older patients when the size of the tumor was larger, when the tumor involved the entire stomach, and when-tissues revealed infiltrative growth, serosal invasion, and lymphatic invasion. Extensive lymph node dissection was performed for 86.6% of the patients, and for these patients the prognosis was better, with a statistical difference. In a multivariate analysis, tumor size, serosal invasion, and extensive lymph node dissection proved to be independent prognostic factors for patients with node-negative gastric cancer.

CONCLUSIONS

Prophylactic lymph node dissection for patients with gastric cancer will prolong the survival time.

Pilot study for preoperative administration of l-OHP to patients with advanced scirrhous type gastric cancer

A new DACH platinum complex, l-OHP, was developed by Kidani as an anticancer agent. A clinical trial took place in Europe which demonstrated its therapeutic efficacy for colorectal cancer. An effective treatment, especially chemotherapy for patients with a advanced scirrhous type gastric cancer, has not yet been established. An in vitro study showed that l-HOP inhibited cell growth in human gastric cancer cell lines. Our pilot study determined the efficacy of preoperative administration of l-OHP, 67 mg/m2 to 100 mg/m2, every 2-3 weeks, for two to three cycles, in five patients with this disease (Stage III and IV) roentogenoscopically and histologically. The platinum concentration in the tissues was also measured. By X-ray examination of the stomach at the time of pre- and post-administration of l-OHP, extension of the lesional gastric wall was observed. Histologically three Grade 2 responses and two Grade 1a responses were obtained according to the criteria presented by Japanese Research Society for Gastric Cancer. The mean platinum concentrations in the lesional tissues were 0.98 ppm and 0.5 ppm in the patients administered l-OHP for three and two cycles respectively. There was no toxicity that prevented surgery. These preliminary results showed the possibility that 1-OHP would be effective for patients with advanced scirrhous type gastric cancer as a neoadjuvant therapy.

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.

Clinicopathologic study of patients with Borrmann type IV gastric carcinoma

Between 1979 and 1993, 665 Japanese patients with advanced gastric cancer underwent surgery at our hospital. These patients were divided into two groups, consisting of 102 patients with Borrmann type IV carcinoma, and the remaining 563 patients with all other types of gastric carcinoma, which were then compared clinicopathologically. In the patients with Borrmann type IV carcinoma, 77.4% of the lesions demonstrated poorly differentiated adenocarcinoma, and 99 patients were classified as Stage III or IV. The resection rate was 87.2% (89/102) with only 39 curative operations despite the fact that 70 total gastrectomies were performed. The incidence of peritoneal dissemination (29.4%) and serosal invasion (97.0%) was significantly higher in these patients. Microscopic lymph node metastasis was positive in 86.5%. The 5-year survival rate was 23.4% in the patients with a curative operation and 5.0% in those with a noncurative operation (p < 0.01). Peritoneal dissemination was most frequently noted in the recurrence patterns. We conclude that early detection and a curative operation are both essential to improve the prognosis of patients with Borrmann type IV gastric cancer. The addition of a potent postoperative chemotherapy regimen is also recommended.

Adenocarcinoma of the gastric cardia

One hundred and ninety-five patients operated on for adenocarcinoma of the gastric cardia during the years 1961-90 were analysed and the present data indicate that the more enthusiastic attitude adopted towards resective surgery led to a significant increase in operative explorations performed and in resectability rate, from 50% (44/88) and 35% (28/88) during the years 1961-75 to 84% (90/107) and 56% (60/107) during the years 1976-90, respectively. The difference between radical resections, 54% (15/28) and 67% (34/60), remained non-significant. The overall postoperative mortality and morbidity after resective surgery were 14% and 35% and these rates did not rise with time. The anastomotic leakage rate was 15%. Anastomotic leakage was, in fact, not only the most common postoperative complication but also the most common cause of death. Overall cumulative survivals at 1, 3 and 5 years were 47%, 11% and 5%. Comparison of the cumulative survival rates between the 15-year periods indicated that there were no differences in overall survival or in survival after resective surgery. We regard these results disappointing, because over half of the patients died in 1 year and because the long-term survival remained dismal.

New trends in surgery for gastric cancer in Japan

Although standard radical gastrectomy for gastric cancer, including lymph node dissection of compartments I and II, has been commonly utilized in Japan, new trends in gastric cancer surgery recently have been developed. In the treatment of early gastric cancer, endoscopic and limited surgeries have become more prevalent, whereas for advanced gastric cancer, super extended radical gastrectomy (SERG) and aggressive adjuvant therapy have been applied. Limited surgery includes wedge resection of the stomach, pylorus-preserving gastrectomy, vagus-preserving gastrectomy, and proximal gastrectomy. The purpose of these more limited techniques is usually to improve quality of life after surgery. Since Takahashi's lymph node staining method using fine activated carbon particles (CH40) made possible systematic para-aortic lymph node dissection, SERG has increased in popularity. The survival rate of patients with para-aortic lymph node metastases who underwent SERG was higher than that of patients who underwent extended radical gastrectomy.

Prognostic value of depth and pattern of stomach wall invasion in patients with an advanced gastric carcinoma

We reviewed data on 467 patients with advanced gastric carcinoma, taking into consideration tumor size, shape and depth of invasion, and growth pattern, either expanding or infiltrative. Three patterns of penetration were identified: i.e., funnel, column, and mountain patterns. The funnel pattern was predominant in tumors extending into the muscularis propria (pm) or subserosa (ss), and were more widely distributed than the column pattern. The majority of the column type tumors were less than 8 cm in pm or ss, and the mountain type was found in only one case in ss, but their size was widely distributed once cancer cells penetrated the serosa. Patients with the funnel type had a better prognosis than the column or the mountain type, and the difference was significant when cancer invasion extended to the serosa.

Adjuvant therapy of gastric cancer: have we made any progress?

Up to now, the majority of adjuvant chemotherapy trials in gastric cancer have failed to show a clear survival benefit as compared to surgical controls, and this is especially true for trials conducted in western countries. But this does not necessarily mean, that adjuvant chemotherapy of gastric cancer is in general ineffective. There are several common threads that appear repeatedly in adjuvant therapy trials which might help to explain the current situation. In most trials stratification was done according to stage and not to the TNM category leading to important stratification bias. A homogeneous surgical approach and a surgical and pathological quality control was not mandatory. There are sufficient data, that in comparison to 'limited' surgery, extended surgery with systematic lymphadenectomy of the N2 compartment markedly improves the prognosis of patients with stage II and IIIa tumors. The kind of chemotherapy, its timing and scheduling, and route of administration might also have been inappropriate to demonstrate a possible benefit of adjuvant therapy. All these things have to be considered seriously in future well designed trials, if an assumed therapeutic gain is to be demonstrated by adjuvant treatment of gastric cancer.

Postoperative PSK and OK-432 immunochemotherapy for patients with gastric cancer

We evaluated the effects of chemotherapy given postoperatively with and without immunomodulators on the survival of patients who had undergone resection for gastric cancer. We conducted a retrospective survey of data on 963 Japanese patients treated at our department of surgery between 1965 and 1987. Data related to the duration of postoperative survival were calculated for those who received chemotherapy, i.e. an individualized combination of various agents given with or without the immunomodulators PSK, a protein extract of the fungus Coriolus versicolor, and/or OK-432, a preparation of an attenuated strain of Streptococcus (immunochemotherapy). Postoperative immunochemotherapy was more often prescribed for patients with advanced disease. The survival of patients who received immunochemotherapy was shorter than that of patients who received only chemotherapy. In a subgroup of patients adjusted for disease stage, the survival of those on chemotherapy versus immunochemotherapy did not differ significantly at any stage. For optimal results, a protocol for postoperative immunochemotherapy needs to be designed and investigated prospectively and according to the stage of gastric cancer. The stage III gastric cancers seem amenable to a favorable response.