BACKGROUND:The prognosis of patients with gastric cancer with peritoneal metastasis is extremely poor. This phase 2 study evaluated the benefits and tolerability of weekly intravenous and intraperitoneal paclitaxel (PTX) treatment combined with oral S-1 in patients with gastric cancer who had macroscopic peritoneal metastasis. METHODS: Patients with gastric cancer who had primary tumors with macroscopic peritoneal metastasis were enrolled. PTX was administered intravenously at 50 mg/m 2 and intraperitoneally at 20 mg/m 2 on days 1 and 8, respectively. S-1 was administered at 80 mg/m 2 per day for 14 consecutive days, followed by 7 days of rest. The primary endpoint was the 1-year overall survival (OS) rate. The secondary endpoints were the response rate, efficacy against malignant ascites, and safety. RESULTS: Thirty-five patients were enrolled. The median number of treatment courses was 11 (range, 2-35). The 1-year OS rate was 77.1% (95% confidence interval, 60.5-88.1). The overall response rate was 71% in 7 patients with target lesions. Malignant ascites disappeared or decreased in 15 of 22 (68%) patients. The frequent grade 3/4 toxic effects were neutropenia (34%), leukopenia (23%), and anemia (9%). CONCLUSIONS: Combination chemotherapy consisting of intravenous and intraperitoneal PTX with S-1 is well-tolerated and effective in patients with gastric cancer who have macroscopic peritoneal metastasis. Cancer 2013;119:3354-8. V C 2013 American Cancer Society.KEYWORDS: phase 2 study; paclitaxel; S-1; gastric cancer; peritoneal metastasis; intraperitoneal chemotherapy. INTRODUCTIONGastric cancer is the fourth most common cancer worldwide and the second leading cause of cancer-related deaths. 1 Multimodal therapy combined with systemic chemotherapy, radiation therapy, and surgery has been developed in the treatment of advanced gastric cancer. 2 Even for noncurable gastric cancer, many clinical trials have been conducted using various newly developed anticancer drugs. In a phase 3 study using docetaxel (DTX), cisplatin, and fluorouracil for recurrent or metastatic gastric cancer patients, the 1-year overall survival (OS) rate and median survival time (MST) were 40% and 9.2 months, respectively. 3 In another phase 3 study using S-1 and cisplatin for unresectable or recurrent gastric cancer, the 1-year OS rate and MST were 54.1% and 13.0 months, respectively. 4 Among patients with noncurable gastric cancer, the prognosis of patients with peritoneal metastasis is extremely poor, 5 and no standard treatment for peritoneal metastasis has been established.One potential treatment approach is the introduction of paclitaxel (PTX), which has been shown to produce a high response rate (29%-36%) for undifferentiated-type adenocarcinoma 6,7 and can be expected to show high efficacy for peritoneal dissemination. The intraperitoneal (IP) administration of PTX was developed to reinforce the drug's effect on peritoneal metastasis. This would be accomplished by making the drug act directly on the nodules at a high concentration. In ...

Background Serum tumor markers have been shown to correlate with the clinical status of patients with advanced gastric cancer. However, the clinical significance of each tumor marker in patients with peritoneal dissemination has not been fully verified. Methods Four serum markers, carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, CA125, and CA72-4, were periodically measured in 102 patients with peritoneal dissemination who received combination intravenous and intraperitoneal chemotherapy. The initial values at diagnosis and after treatment were analyzed in association with clinicopathological factors, response to chemotherapy, and overall survival. Results The sensitivities of CEA, CA19-9, CA125, and CA72-4 for peritoneal metastasis at the initial diagnosis were 19, 36, 46, and 45%, respectively. The CA125 level was significantly correlated with the degree of peritoneal dissemination and the existence of malignant ascites. Patients with ovarian metastasis showed significantly higher levels of CA72-4. The median survival time of patients with an elevated CA125 level was significantly shorter than that of patients with a normal CA125 level (36.7 vs. 16.6 months, p \ 0.001). Multivariate analysis showed that the degree of peritoneal metastasis and an elevated CA125 level were independent prognostic factors. Normalization of the CA125 level after 3 courses of chemotherapy was correlated with reduced ascites and improved survival.Conclusions Serum CA125 and CA72-4 are clinically useful markers in diagnosis, evaluating the efficacy of chemotherapy, and predicting the prognosis of patients with peritoneal dissemination. From an academic point of view, periodic measurements of these markers are warranted in gastric cancer patients with possible peritoneal dissemination.

Colorectal mixed adenoneuroendocrine carcinoma (MANEC), which acts like an aggressive tumor, is a rare clinical manifestation on which only a limited amount of literature exists. Surgical resection by regional lymphadenectomy is considered as the only curative treatment for colorectal MANEC, and adjuvant chemotherapy or radiotherapy is recommended because of its high recurrence rate. Colorectal MANEC is frequently diagnosed at an advanced stage, when it is unresectable, and chemotherapy plays a central role in its treatment. Pathological confirmation of the target lesion component is critical for regimen selection. If the lesion comprises an adenocarcinomatous component, a regimen for colorectal adenocarcinoma should be administered. For lesions comprising mainly a neuroendocrine carcinomatous component, cisplatin combined with etoposide or irinotecan has proven to be clinically appropriate. Everolimus, a mechanistic target of rapamycin pathway inhibitor, also improves survival. Sunitinib malate, another molecular targeting agent, is effective for treating neuroendocrine carcinoma; however, the evidence on its effectiveness for treating gastrointestinal neuroendocrine carcinoma is insufficient.

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.

Hyaluronan (HA) is a promising drug carrier for cancer therapy because of its CD44 targeting ability, good biocompatibility, and biodegradability. In this study, cisplatin (CDDP)-incorporating HA nanogels were fabricated through a chelating ligand-metal coordination cross-linking reaction. We conjugated chelating ligands, iminodiacetic acid or malonic acid, to HA and used them as a precursor polymer. By mixing the ligand-conjugated HA with CDDP, cross-linking occurred via coordination of the ligands with the platinum in CDDP, resulting in the spontaneous formation of CDDP-loaded HA nanogels. The nanogels showed pH-responsive release of CDDP, because the stability of the ligand-platinum complex decreases in an acidic environment. Cell viability assays for MKN45P human gastric cancer cells and Met-5A human mesothelial cells revealed that the HA nanogels selectively inhibited the growth of gastric cancer cells. In vivo experiments using a mouse model of peritoneal dissemination of gastric cancer demonstrated that HA nanogels specifically localized in peritoneal nodules after the intraperitoneal administration. Moreover, penetration assays using multicellular tumor spheroids indicated that HA nanogels had a significantly higher ability to penetrate tumors than conventional, linear HA. These results suggest that chelating-ligand conjugated HA nanogels will be useful for targeted cancer therapy.