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Yutaka Yonemura

Publications and source records attributed to Yutaka Yonemura.

At least 19 recordsLinked to original sources

Recent advances in the treatment of peritoneal dissemination of gastrointestinal cancers by nucleoside antimetabolites.

Peritoneal dissemination is the most common cause of metastasis from malignancies in the abdominal cavity. There are no standard treatments for peritoneal dissemination and the results are poor. The reasons for this are as follows: (1) no effective chemotherapeutic agents have been identified or developed; (2) surgical cytoreduction has little effect on survival improvement; and (3) the molecular mechanisms of peritoneal dissemination have not been clarified and no therapy against the target molecules has been developed. However, studies on the molecular mechanisms of peritoneal dissemination have elucidated some of the target molecules and the development of new multimodal therapies has also improved survival. Early postoperative intraperitoneal chemotherapy, hyperthermic intraperitoneal perfusion chemotherapy and neoadjuvant intraperitoneal-systemic chemotherapy have been newly developed, and a novel surgical therapy named peritonectomy has been proposed to perform complete cytoreduction of peritoneal dissemination. At present, these approaches appear to be effective therapeutic modalities for peritoneal dissemination. However, TS-1 and capecitabine have shown worthwhile results in recent clinical trials for patients with advanced gastric cancer. We recently found that newly developed antitumor cytosine nucleoside analogs show a survival advantage in peritoneal dissemination models using human cancer cells. These non-fluoropyrimidine nucleosides may potentially help to improve the poor prognosis observed in patients with advanced cancers involving peritoneal dissemination.

Adenocarcinoma↗

Evaluation of lymphatic invasion in primary gastric cancer by a new monoclonal antibody, D2-40.

Lymphatic invasion is known as an independent predictor of lymph node metastasis in gastric cancer. However, the diagnosis of lymphatic invasion is sometimes difficult by hematoxylin-eosin (H&E) staining. Immunostaining using D2-40 was performed to study the distribution of lymphatic vessel and lymphatic invasion in a series of 78 primary gastric cancers. D2-40 showed specific staining for the lymphatic vessels, but not for blood vessels. The lymphatic invasion was most frequently found in the upper half of submucosal layer. Positive rate of lymphatic invasion by H&E staining was 27% (21/78), and that by D2-40 was 44% (34/78). Lymphatic invasion on H&E staining was diagnosed as false negative in 17 (21.8%) of 78 primary gastric cancers and false positive in 4 (5.1%) of 78 primary gastric cancers. Sensitivity for lymph node metastasis by the lymphatic invasion diagnosed by D2-40 was significantly higher (89%, 24/27) than by H&E staining (41%, 11/27). These results suggest that the diagnosis of lymphatic invasion by D2-40 is more sensitive than H&E staining. Sensitivity for the prediction of lymph node metastasis from the lymphatic invasion status in primary tumor by D2-40 was significantly higher than by H&E staining. Based on our results, we recommend the use of D2-40 immunoreactions for the routine evaluation of lymphatic invasion in gastric cancer.

Adenocarcinoma↗

Proteomic analysis of a highly metastatic gastric cancer cell line using two-dimensional differential gel electrophoresis.

Stomach cancer is still a major cause of death in Asian people despite a complete cure after the resection of early cancers, mainly because peritoneal dissemination is difficult to treat. In the present study, we used two-dimensional differential gel electrophoresis (2-D DIGE) to identify specific proteins differentially expressed between a highly metastatic stomach cancer cell line MKN-45-P and its parental cell line MKN-45. We detected 27 protein spots in at least 2 of 3 experiments which showed statistically significant differences in abundance. All 27 protein spots were identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) and database-searching software. A proteomic analysis revealed 13 different proteins with some isoforms sharing different biochemical characteristics, and that 8 proteins were up-regulated, and 5 were down-regulated. The 13 proteins were mainly involved in protein synthesis (transfer RNA synthetase), metabolism (flavoprotein subunit, pyruvate kinase, adenylate kinase), receptor and signal transduction (annexins I and A2), the cytoskeleton (keratin 5, cytokeratin 8) and cell cycling (ts11). These results suggested that a proteomic approach including 2-D DIGE would be an efficient way to identify the proteins responsible for specific biological functions. Moreover, these observations might be novel findings leading to the prediction of postoperative peritoneal recurrence.

Cell Line, Tumor↗

[A case of complete peritonectomy for primary ovarian pseudomyxoma].

A 64-year-old woman had an abdominal distention in February 2002. She was diagnosed with primary ovarian pseudomyxoma. She received a hysterectomy and bilateral salpingo oophorectomy in April 2002. Then, she was referred to our hospital the same year. In October 2002, she received peritonectomy with resection of the hepatic capsule, diaphragmatic peritoneum, pelvic peritoneum, greater omentum and the spleen. Intraperitoneal CDDP administration was done on days 1 and 2 after peritonectomy. She is still alive without recurrence for 3 years after the peritonectomy operation.

Female↗

The diagnostic value of PET-CT for peritoneal dissemination of abdominal malignancies.

AIM: To evaluate the diagnostic value of PET-CT for predicting peritoneal metastasis of abdominal malignancies. METHODS: One hundred fifty four (154) cases of malignant tumor, including 141 cases of gastric cancer, 9 cases of colon cancer, 2 cases of ovary cancer, and 2 cases of pseudomyxoma, had accepted PET CT from Nov. 2002 to Jan. 2006. One hundred twenty three (123) had also accepted high speed spiral CT (HSSCT) as control. The results were compared with peritoneal lavage, pathological examination and clinical manifestation. RESULTS: The accuracy of PET-CT for peritoneal metastasis was 87.7%, with sensitivity 72.7%, specificity 93.6%, PPV 82.1% and NPV 89.6%. HSSCT showed an accuracy of 79.7%, sensitivity 47.4%, specificity 94.1%, PPV 78.3%, and NPV 80.0%. PET-CT had significantly better sensitivity than HSSCT (p < 0.05). For gastric cancer patients alone, PET CT had an accuracy of 87.9%, sensitivity 74.4%, specificity 93.1%, PPV 80.6% and NPV 90.5%, significantly better than HSSCT's 78.1, 39.4, 93.8, 72.2, and 79.2% (p < 0.01), respectively. In case of Cy1P0, PET-CT showed a seemingly better sensitivity of 53.3% vs. 13.3% of HSSCT, although not statistically significant because of the number of observations (p = 0.053). And in P1 cases, PET-CT and HSSCT manifested sensitivity of 84.2% vs 63.2%, respectively, without significance (p = 0.141). CONCLUSION: PET-CT is useful in predicting peritoneal metastasis of malignancies.

Abdominal Neoplasms↗

[The results of surgical treatment for pseudomyxoma peritonei].

The surgical results of 37 patients with pseudomyxoma pertonei are reported. Twenty eight patients received laparotomy and complete cytoreduction (CC-0) could be done in 6 patients. However, 13 patients received incomplete cytoreduction, and 9 patients underwent drainage of ascites and peritoneal washing. The Peritoneal Carcinomatosis Index (PCI) was less than 20 in CC-0 patients. CC-0 patients survived significantly better than patients with residual disease. Accordingly, peritoneal washing to remove free cancer cells should be aimed for complete cytoreduction of the solid mucinous nodules.

Adult↗

S100A4 regulates E-cadherin expression in oral squamous cell carcinoma.

S100A4 has multiple functions in cell cycle progression and cell motility, and has been implicated in cancer invasion. In this study, we examined the expression of S100A4, E-cadherin and its related proteins in oral squamous cell carcinoma (SCC) cell lines with different invasive phenotypes, grade 4C and 4D. Furthermore, grade 4C OSC-19 cells expressing E-cadherin were transfected with S100A4-expression vector and the expression of E-cadherin-related proteins in the stable clone was examined to elucidate the relationship between S100A4 and E-cadherin. Constitutive over-expression of S100A4 in stable transformant of OSC-19 (OSC-19/S100A4) cells led to down-regulation of E-cadherin and beta-catenin. Furthermore, grade 4D invasive cell lines (HOC313 and TSU) expressing S100A4 mRNA did not express E-cadherin, P-cadherin, and beta-catenin, while gamma-catenin protein was only weakly expressed. Thus, the mRNA expression of E-cadherin was reversely correlated with S100A4 expression in oral SCCs. Interestingly, vascular endothelial growth factor-C was up-regulated in OSC-19/S100A4 cells. In summary, S100A4-mediated regulation of E-cadherin expression may play an important mechanism in invasion and metastasis of oral SCC.

Cadherins↗

Role of VEGF-C and VEGF-D in lymphangiogenesis in gastric cancer.

BACKGROUND: The molecular mechanisms of lymphangiogenesis induced by vascular endothelial growth factor (VEGF)-C and VEGF-D in gastric cancer were studied. METHODS: VEGF-C and VEGF-D gene expression vectors were transfected into the gastric cancer cell line KKLS, which did not originally express VEGF-C and VEGF-D, and stable transfectants (KKLS/VEGF-C and KKLS/VEGF-D) were established. The cell lines were inoculated into the subserosal layer of the stomach and subcutaneous tissue of nude mice. RESULTS: VEGF-C and VEGF-D expression in KKLS/VEGF-C and KKLS/VEGF-D cells was found by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Expression of mouse VEGF receptor (VEGFR)-2 and mouse VEGFR-3 mRNA was detected in the KKLS/VEGF-C and KKLS/VEGF-D gastric tumors. Newly formed lymphatic vessels were detected not only in the periphery but also in the center of the tumors. The intratumor lymphatic vessels connected with the preexisting lymphatic vessels in the muscularis mucosa. The average numbers of lymphatic vessels in KKLS/VEGF-C (52.0 +/- 9.5) and KKLS/VEGF-D (16.4 +/- 0.6) gastric tumors were significantly higher than that in the KKLS/control vector tumors (4.0 +/- 1.4). CONCLUSION: VEGF-C and VEGF-D may induce neoformation of lymphatic vessels in experimental gastric tumors by the induction of VEGFR-3 expression.

Animals↗

Pharmacokinetic advantage of intraperitoneal injection of docetaxel in the treatment for peritoneal dissemination of cancer in mice.

Intraperitoneal administration of docetaxel has been used to treat peritoneal dissemination of cancer, but its safety has not yet been confirmed. We have compared the pharmacokinetic behaviour of docetaxel after intravenous and intraperitoneal administration in CD-1-nu/nu mice bearing MKN45P, a gastric cancer variant line producing peritoneal dissemination. Docetaxel (8 mg kg(-1)) was intravenously or intraperitoneally injected into the mice and at designated times the drug concentration was measured in plasma, ascites fluid, and abdominal tissues (liver, kidney, intestine and spleen, solid cancer, and suspended free cancer). The pharmacokinetic behaviour of docetaxel was similar in control mice and cancer-bearing mice after administration via either route, except that the transfer of docetaxel from the abdominal cavity to systemic blood (plasma) was slower in cancerbearing mice than in control mice. As expected, the intraperitoneal drug concentration was much higher (approximately 100-fold) and was maintained for a longer time in the intraperitoneal injection group than in the intravenous injection group. The drug concentrations in peritoneal solid cancer tissue and suspended free cancer cells were also significantly higher for a longer time in the intraperitoneal injection group than in the intravenous injection group. The values of the plasma area under concentration-time curves (AUC) were similar for both administration routes. The ratio of AUC ascite/AUC plasma after intraperitoneal administration was higher than after intravenous administration. The drug concentration in abdominal organs after intraperitoneal injection was lower during the first 2 h, then became similar to those after intravenous injection. These results indicated that the intraperitoneal administration of docetaxel for peritoneal dissemination was likely to be an effective treatment method, without causing any increase in systemic toxicity.

Animals↗

[Effect of intraperitoneal chemotherapy on experimental peritoneal dissemination of gastric cancer].

In vitro chemosensitivity test using a collagen-gel method was done on 165 primary gastric cancers. All of 5-FU, CBDCA, CDDP and docetaxel showed a high sensitivity. The effects of per oral (po) administration of TS-1, a combination of po TS-1 and intraperitoneal (ip) administration of CDDP, ip 5-FU and ip docetaxel, were evaluated in athymic mice bearing peritoneal dissemination of a gastric cancer cell line (MKN-45-P that shows a high rate of metastasis to the peritoneal cavity of nude mice). Nude mice were inoculated by ip with 10(7) MKN-45-P cells. No survival benefit was obtained after po administration of TS-1 (12 mg/kg) alone or ip CDDP alone. However, a combination of po TS-1 (8 mg/kg x 10 days, from day 3) and ip CDDP (3.5 mg/kg, day 6 and 13) showed a significant survival improvement than that of po TS-1 or ip CDDP treatment alone. ip administration of 30 mg/kg (3 times/week x 3 weeks) or 15 mg/kg (6 times/week x 3 weeks) of 5-FU significantly improved the survival of mice bearing MKN-45-P. 5-FU concentration of ascites after ip administration of 30 mg/kg of 5-FU was 600-fold higher than po administration of 12 mg/kg of TS-1 at peak level. ip injections of docetaxel of 8 mg/kg, and 2 mg/kg improved the survival of 4 and 1 mice, respectively, and they were tumor-free on day 90. Survival of mice treated with ip injection of CBDCA (100 mg/kg, on day 3, or 50 mg/ kg on day 3 and 10) was significantly better than the control group. These results suggest the potential of po TS-1 + ip CDDP, ip 5-FU, ip docetaxel and ip CBDCA administration for the treatment of peritoneal dissemination of gastric cancer.

Animals↗

Effect of intraperitoneal administration of docetaxel on peritoneal dissemination of gastric cancer.

The effect of intraperitoneal (i.p.) administration of docetaxel was evaluated for preclinical evidence of anticancer activity in athymic mice bearing a gastric cancer cell line, MKN-45-P that shows a high rate of metastasis to the peritoneal cavity of nude mice. Nude mice were inoculated i.p. with 10(7) MKN-45-P cells. On days 2, 5, 9, 12, 16 and 19 after tumor inoculation, mice were treated with i.p. injection of docetaxel. Treatment doses of docetaxel were 8 mg/kg (N = 7) 2 mg/kg (N = 7) and 0.5 mg/kg (N = 7). Intraperitoneal carcinoembryonic antigen (CEA) levels, animal body weight, mortality and survival were determined. All control mice developed ascites and died within 19-40 days. The median survival time in the control group was 32 days, while those of mice treated with 8, 2 and 0.5 mg/kg were 90, 63 and 49.5 days, respectively. One of seven mice treated with 8 mg/kg of docetaxel died of toxicity on day 12. Four mice were tumor-free on day 90, but two had tumors in the abdomen when autopsied on day 90. One mouse treated with 2 mg/kg was ascertained to be tumor-free on day 90. All seven mice treated with 0.5 mg/kg of docetaxel died of peritoneal dissemination within 71 days. The results suggest the potential of intraperitoneal docetaxel administration for the treatment of peritoneal dissemination of gastric cancer.

Animals↗

Correlation of S100A4 expression with invasion and metastasis in oral squamous cell carcinoma.

S100A4 is known to be involved in cancer cell motility by virtue of its ability to activate non-muscle myosin. In the current study, we investigated the interrelationship of clinico-pathological findings and S100A4 expression in oral squamous cell carcinoma (SCC). The expression of S100A4 was examined immunohistochemically in 41 clinical specimens of oral SCC. S100A4 expression was detected in 11 (26.8%) of 41 cases. Although the expression of S100A4 was not associated with the primary tumor site and degree of differentiation, there was a significant correlation between the increased S100A4-expression and the mode of invasion (p < 0.0001). In addition, the S100A4 status showed a clear correlation with lymph node metastasis (P < 0.01). These results lead us to conclude that S100A4 expression status may be a useful prognostic factor in patients with invasive and metastatic oral SCCs.

Carcinoma, Squamous Cell↗

Severe hypoglycemia and hypokalemia in association with liver metastases of gastric cancer.

We report an 80-year-old man who presented with non-islet cell tumor hypoglycemia (NICTH) in association with hepatic recurrence of gastric cancer. His serum potassium was reduced from 3.9 to 3.1 mmol/l 5 weeks after gastrectomy, and he subsequently developed hypoglycemic coma. He was diagnosed as having NICTH because of the presence of serum big IGF-II and positive staining for IGF-II in gastric cancer cells obtained at surgery. A computed tomography showed multiple liver metastases. His hypoglycemia was refractory to steroid therapy. This case suggested that NICTH could develop in association with hepatic metastases of gastric cancer. Unexpected hypokalemia may be a manifestation of occult NICTH.

Adenocarcinoma↗

[Treatment results of peritoneal dissemination from gastric cancer by neoadjuvant intraperitoneal-systemic chemotherapy].

UNLABELLED: No standard treatment exists for peritoneal dissemination from gastric cancer. We reviewed our experience using a novel treatment consisting of peritonectomy and intraoperative chemo-hyperthermic peritoneal perfusion (CHPP). Records of all patients who underwent CHPP and cytoreductive surgery from 1992 to 2001 were reviewed. RESULTS: Data from 107 patients (average age, 52 years) were available. P3 dissemination was found in 72 patients, and 8 and 27 patients showed P1 or P2 dissemination, respectively. Peritoneal metastasis was synchronous in 75 and metachronous in 32 patients. All patients received CHPP after cytoreductive surgery. Peritonectomy was performed in 42 patients. Complete cytoreduction (CC-0) was achieved in 47 patients (44%). Peritonectomy, resulted in CC-0 in 69% (29/42), but CC-0 was achieved in 18 of 65 (28%) patients by ordinary surgical techniques. There were 23 postoperative complications (21%) after operation. The overall operative mortality was 2.8% (3/107). Median follow-up for the entire study group was 46 months. Seventeen patients (15%) were disease-free, and 90 patients were dead at the time of analysis. Eighty-seven deaths were related to progression of disease. The median survival of all patients was 16.2 months, with an actual 5-year survival of 6%. Median survival of CHPP plus ordinary cyoreduction was 12.0 months and that after CHPP and peritonectomy was 22.8 months. Completeness of cytoreduction and peritonectomy were significant prognostic factors on univariate analysis and 5-year survival rate was 27%. Lymph node status, grade of peritoneal dissemination (P1-2 vs P3), age (>60 years vs <60 years), tumor volume of dissemination (>2.5 cm vs <2.5 cm in diameter), and histologic type (differentiated vs. poorly differentiated type) did not affect survival. The cox proportional model demonstrated that completeness of cytoreduction was the strongest prognostic factor. Patients who had an incomplete resection had 2.8-fold higher risk of dying from disease than patients who underwent complete cytoreduction. The 5-year survival after complete cytoreduction was 12%, compared with 2% for incomplete resection. Four patients lived more than 5 years. Cytoreduction was incomplete in one 5-year survivor who showed complete response to CHPP. CONCLUSION: Complete cytoreduction using peritonectomy and CHPP may improve survival of patients with peritoneal dissemination from gastric cancer. This procedure is most appropriate for highly motivated patients who are committed to survive as long as possible.

Analysis of Variance↗

REG gene expression is associated with the infiltrating growth of gastric carcinoma.

BACKGROUND: The Reg gene is known to be involved in the growth of not only pancreatic B-cells, but also epithelial cells of the gastrointestinal tract and carcinoma of its lineage. METHODS: Because, to the authors' knowledge, no studies have been reported regarding REG expression in gastric carcinoma, the authors investigated REG mRNA and REG protein expression using reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot analysis, and immunohistochemical study and correlated the results with the clinical features of gastric carcinoma. RESULTS: Using RT-PCR and Western blot analyses, reg mRNA and 16-kilodalton REG proteins were detected in two of eight human gastric carcinoma cell lines. Cytoplasmic localization of REG proteins in the cell lines was confirmed by fluorescent immunocytochemistry. The RT-PCR analysis revealed the presence of REG mRNA in as many as 77% (87 of 112 tumors) of primary gastric carcinoma tumors. Screening of a total of 195 patients with primary gastric carcinoma using immunoperoxidase staining revealed positive REG immunoreactivity in 60 of the 195 primary tumors (31%). REG expression in infiltrating tumors was found to be significantly higher compared with localized tumors (P < 0.05). Strong REG expression was noted in the cytoplasm of signet ring cell carcinoma tumors at a significantly higher incidence than in nonsignet ring cell tumors. Moreover, patients with REG-negative differentiated adenocarcinoma were found to have a significantly better prognosis compared with patients with REG-positive tumors. The incidence of venous invasion of REG-positive tumors was significantly higher than that of REG-negative tumors. CONCLUSIONS: The results of the current study suggest that the expression of the REG gene is closely related to the infiltrating property of gastric carcinoma, and may be a prognostic indicator of differentiated adenocarcinoma of the stomach.

Adenocarcinoma↗

Gastrectomy, peritonectomy, and perioperative intraperitoneal chemotherapy: the evolution of treatment strategies for advanced gastric cancer.

Gastric cancer disseminates by hematogenous, lymphatic, and transcoelomic routes. For maximal containment of the malignant process, perioperative intraperitoneal chemotherapy is necessary in two groups of patients in whom the primary cancer can be resected. Those patients who have been resected for cure and have a high likelihood of microscopic residual disease require intraperitoneal chemotherapy. This includes all T3 and T4 patients, and patients with N2 nodes present. A series of randomized and nonrandomized clinical studies have established the benefits of perioperative intraperitoneal chemotherapy in this group of patients. Patients with stage IV disease who are able to undergo a palliative resection require these treatments if peritoneal seeding is observed. Systemic chemotherapy is largely ineffective for peritoneal seeding, while intraperitoneal chemotherapy is most likely to produce a response with small volume, surgically debulked carcinomatosis. In addition, intraperitoneal chemotherapy can eliminate the future development of debilitating ascites. Sufficient data are available from the gastric cancer literature to support the use of these combined treatments on a routine basis if the primary cancer is resectable and gastrointestinal function can be reestablished.

Antineoplastic Combined Chemotherapy Protocols↗

Expression of collagenase-3 (matrix metalloproteinase-13) in human gastric cancer.

BACKGROUND: Collagenase-3 (matrix metalloproteinase-13; MMP-13) is a recently identified member of the matrix metalloproteinases (MMPs) with broad substrate specificity, and a potential role in tumor metastasis and invasion has been proposed for this enzyme. To date, in gastrointestinal tract tumors, collagenase-3 expression has been reported only in esophageal carcinoma; the presence and possible implications of this enzyme in the progression of gastric cancer are unknown. METHODS: In this study, MMP-13 mRNA expression was analyzed in a series of 110 matched gastric adenocarcinomas and the corresponding adjacent normal mucosae as well as in nine gastric cancer cell lines. In addition, the mRNA expression of gelatinase a (MMP-2) and membrane type-1 matrix metalloproteinase (MT1-MMP), two MMPs which have the ability to activate MMP-13 in vitro, was also examined in the same cases and cell lines. the production and localization of MMP-13, MMP-2, and MT1-MMP were investigated by immunohistochemistry, immunofluorescence, western blot analysis, and zymography. RESULTS: MMP-13 mrna was expressed in 23 of the 110 carcinomas (21%), and MT1-MMP mRNA was expressed in 45 (40%), but no MMP-13 or MT1-MMP mRNA was detected in any of the normal mucosae. Also, eight of the nine gastric cancer cell lines expressed mRNA of MMP-13, and in each cell line there was coordinate expression with either MT1-MMP or MMP-2 mRNA. MMP-13 and MT1-MMP were detected at the bases of invadopodia of the cultured cancer cells as well as in the invasive front of the tumors, as shown by immunofluorescence and immunohistochemistry, respectively. Western blot analysis revealed the presence of MMP-13 protein in those cell lines and carcinomas that expressed its mrna. on zymography, almost all cell lines that expressed MMP-13 showed gelatinolytic bands corresponding to the active form of MMP-13 or one of its intermediate forms. Also, zymographic analysis of the tumor specimens revealed strong gelatinolytic bands of MMP-13 and MMP-2, whereas these bands in normal mucosa were weak. There was no significant relationship between MMP-13 mRNA expression and histologic type, lymph node metastasis, wall invasion, or distant metastasis. However, patients with MMP-13 mRNA-positive tumors had a poorer prognosis than those with MMP-13-mrna-negative cancer. Furthermore, patients with simultaneous expression of MMP-13 and MT1-MMP mRNA showed the poorest prognosis, as compared with those having tumors expressing either MMP-13 or MT1-MMP, or neither MMP-13 nor MT1-MMP mRNA. CONCLUSION: These findings suggest that MMP-13 expression may contribute to the progression of gastric cancer, and its coordinate overexpression with MT1-MMP and/or MMP-2 may have a cooperative effect in the progression of gastric cancer.

Adenocarcinoma↗

Effective therapy for peritoneal dissemination in gastric cancer.

Peritoneal dissemination is the most frequent cause of death from gastric cancer, accounting for death in 20% to 40% of patients. Preoperative intraperitoneal chemotherapy, peritonectomy, intraoperative chemohyperthermic perfusion, and early postoperative intraperitoneal chemotherapy are treatment modalities specifically designed to eliminate peritoneal dissemination and progression. Preoperative intraperitoneal chemotherapy is for containment of peritoneal free cancer cells, and also may facilitate complete eradication of visible peritoneal dissemination by peritonectomy. Further, complete cytoreduction can be achieved more often when peritonectomy is included in the surgical treatment of gastric cancer with peritoneal dissemination. Phase III data shows prolonged survival attributed to complete cytoreduction. Aggressive cytoreduction of peritoneal dissemination by peritonectomy can reduce residual tumor burden to micrometastases on the peritoneal surface that can be treated by intraoperative intraperitoneal chemotherapy and early postoperative intraperitoneal chemotherapy. Among all these modalities, surgical cytoreduction is probably the most important for survival benefit. If the surgical cytoreduction is visibly incomplete, prolonged survival cannot be expected, despite subsequent treatment. The surgeon's goal is to reduce the cancer cell burden to a microscopic level. Continued refinement of phase II studies is needed for maximal benefit and to standardize the technical and chemotherapeutic options of each modality.

Adult↗