Salvage gastrectomy after intravenous and intraperitoneal paclitaxel (PTX) administration with oral S-1 for peritoneal dissemination of advanced gastric cancer with malignant ascites

BACKGROUND

Peritoneal metastasis of gastric cancer has extremely poor clinical outcomes. Recently, we developed a combination chemotherapy that used intraperitoneal (IP) paclitaxel (PTX) and produced excellent antitumor effects against peritoneal lesions. However, no information is available about the benefit of gastrectomy in cases with malignant ascites.

METHODS

A total of 64 patients with severe peritoneal metastasis and ascites received IP PTX at 20 mg/m(2) via implanted subcutaneous peritoneal access ports as well as intravenous (IV) PTX at 50 mg/m(2) on days 1 and 8. S-1 was administered at 80 mg/m(2) day for 14 consecutive days, followed by 7 days of rest. In all patients, investigative laparoscopy was performed around the combination chemotherapy, and gastrectomy was performed on patients who showed apparent shrinkage of their peritoneal nodules as well as negative peritoneal cytology at the second laparoscopy.

RESULTS

Gastrectomy was performed in 34 patients. The median course of chemotherapy before surgery was 5 courses (range 2-16). R0 operation was achieved in 22 patients (65%), and grade 2 and 3 histological responses were obtained in 7 (21%) and 1 (3%) patient(s), respectively. The median survival time and 1-year overall survival of the gastrectomized patients were 26.4 months and 82%, and those of the 30 patients who did not receive gastrectomy were 12.1 months and 26%, respectively. Morbidity was minimal, and there was no mortality.

CONCLUSIONS

Salvage gastrectomy after chemotherapy of S-1 with IV and IP PTX is promising, even for patients with highly advanced gastric cancer and severe peritoneal metastasis and malignant ascites.

Treatment strategies for gastric cancer patients with peritoneal metastasis

Although the treatment of gastric cancer improves the clinical outcomes, the survival of gastric cancer patients with peritoneal metastasis is still very poor. Effective drugs against peritoneal metastasis, coupled with new therapeutic modalities, are needed to improve the prognoses of these patients. Paclitaxel and TS-1 are candidate drugs for peritoneal metastasis, and intraperitoneal chemotherapy and targeted therapy are potential new therapeutic modalities. Two phase II studies using TS-1 and intraperitoneal and systemic paclitaxel for gastric cancer patients with peritoneal metastasis showed respectable survival results. In addition, peritoneal metastatic lesions showed high levels of epithelial cellular adhesion molecule (ECAM) and very low levels of human epidermal growth factor receptor 2 (HER2), thus indicating that an anti-ECAM monoclonal antibody, catumaxomab, would be effective against gastric cancer-derived peritoneal metastasis. Although catumaxomab and intraperitoneally administered paclitaxel are not generally used in Japan at present, these treatment strategies might therefore be effectively used in Japan in the near future.

Fluoropyrimidine plus cisplatin for patients with advanced or recurrent gastric cancer with peritoneal metastasis

BACKGROUND

There are few data on the efficacy of combination chemotherapy with a fluoropyrimidine plus cisplatin for patients with advanced or recurrent gastric cancer (AGC) complicated by peritoneal metastasis, especially massive ascites.

METHODS

We retrospectively evaluated the efficacy and safety of a fluoropyrimidine (S-1 or capecitabine) plus cisplatin as first-line chemotherapy in 120 patients with AGC and peritoneal metastasis.

RESULTS

Ascites was detected in 50 patients, with 11 patients having massive ascites. Median progression-free survival (PFS) and overall survival (OS) of all patients was 6.1 and 15.9 months, respectively. The PFS and OS were shorter in patients with massive ascites (n = 11; 3.7 and 9.5 months) compared with patients with small or moderate ascites (n = 39; 5.8 and 13.5 months) or patients without ascites (n = 70; 6.9 and 18.1 months). The objective response in terms of ascites was similar whether ascites was massive (4 of 11 patients; 36.4%) or small or moderate (16 of 39 patients; 41%). The frequencies of grade 3 or higher toxicity or treatment discontinuation due to toxicity are relatively similar across ascites groups.

CONCLUSIONS

Fluoropyrimidine plus cisplatin appears to be tolerated in selected patients with peritoneal metastasis.

First-line fluorouracil-based chemotherapy for patients with severe peritoneal disseminated gastric cancer

BACKGROUND

Treatment with an oral fluoropyrimidine plus cisplatin is widely used for advanced gastric cancer, but patients with severe peritoneal metastasis often cannot tolerate such treatment, due to inadequate oral intake or massive ascites. The aim of this study was to assess the efficacy and safety of systemic chemotherapy for advanced gastric cancer with severe peritoneal metastasis.

METHODS

The cases of 92 patients with advanced gastric cancer and severe peritoneal metastasis who received first-line chemotherapy at our hospital between May 2001 and February 2007 were retrospectively analyzed. Severe peritoneal metastasis was defined as massive ascites or inadequate oral intake due to peritoneal dissemination. Inadequate oral intake was defined as having required an intravenous drip infusion.

RESULTS

All 92 patients received 5-fluorouracil (5-FU)-based chemotherapy; 40 of the patients had massive ascites, 34 had inadequate oral intake, and the remaining 18 had both conditions. Among the 86 patients having assessable ascites, 23 (27%) patients showed an improvement in ascites. Of the 52 patients with inadequate oral intake, 17 (33%) patients improved to the point of ingesting without intravenous drip infusion after receiving the chemotherapy. Median time to treatment failure and overall survival time were 1.9 months [95% confidence interval (CI) 1.3-2.5 months] and 4.6 months (95% CI 3.9-5.3 months), respectively. Major grade 3 or 4 adverse events were anorexia (26%), neutropenia (26%), and anemia (22%).

CONCLUSION

The treatment regimen of 5-FU-based chemotherapy for advanced gastric cancer with severe peritoneal metastasis was feasible, but its efficacy was not sufficient.