Laparoscopic resection of a gastrointestinal stromal tumor of the rectum after treatment with imatinib mesylate: report of a case.

This report describes the laparoscopic resection of a rectal GIST after treatment with imatinib mesylate. A 56-year-old male presented with a submucosal tumor (longest diameter, 8 cm) arising in the lower rectum. A core needle biopsy revealed that the tumor contained bundles of spindle-like cells.

Short- and long-term outcomes of laparoscopic surgery in patients with pathological stage II and III colon cancer.

Background/aims: In Japan, the safety and long-term outcomes of laparoscopic surgery for advanced colorectal cancer remains a matter of debate. We studied the safety and outcomes of laparoscopic surgery in patients with pathological stage II and III colon cancer.

Methodology: The study group comprised 253 patients with colon cancer who underwent laparoscopic surgery from January 1998 through December 2006.

Oncological outcomes of laparoscopic surgery in elderly patients with colon cancer: a comparison of patients 64 years or younger with those 75 years or older.

Background/aims: We compared the results of laparoscopic resection of colon cancer between patients 75 years or older and those 64 years or younger, to confirm whether this procedure is warranted in elderly patients.

Methodology: The study group was comprised of patients with stage I to III colon cancer treated by laparoscopic surgery from 1995 through 2006. Oncologic outcomes were compared between 74 patients 75 years or older (elderly group) and 74 patients 64 years or younger (younger group) who were matched for gender, tumor location and pathological tumor-node-metastasis (TNM) stage.

mPGES-1-expressing bone marrow-derived cells enhance tumor growth and angiogenesis in mice.

Microsomal prostaglandin (PG) E synthase 1 (mPGES-1) is a major PGE synthase and has recently been reported to be expressed at high levels in several cancer types. We previously reported that the PGE receptor EP3 is expressed in bone marrow (BM) derived cells, enriched in stromal tissue, and enhances the potential for tumor angiogenesis. In the present study, we examined the role of mPGES-1-expressing BM cells on tumor angiogenesis using BM chimeric mice.

COX-2 and prostaglandin EP3/EP4 signaling regulate the tumor stromal proangiogenic microenvironment via CXCL12-CXCR4 chemokine systems.

Bone marrow (BM)-derived hematopoietic cells, which are major components of tumor stroma, determine the tumor microenvironment and regulate tumor phenotypes. Cyclooxygenase (COX)-2 and endogenous prostaglandins are important determinants for tumor growth and tumor-associated angiogenesis; however, their contributions to stromal formation and angiogenesis remain unclear. In this study, we observed that Lewis lung carcinoma cells implanted in wild-type mice formed a tumor mass with extensive stromal formation that was markedly suppressed by COX-2 inhibition, which reduced the recruitment of BM cells.

Host prostaglandin EP3 receptor signaling relevant to tumor-associated lymphangiogenesis.

Prostaglandin E(2) (PGE(2)) and prostaglandin E (EP) receptor signaling pathways have been implicated in the promotion of tumor growth and angiogenesis. However, little is known about their roles in lymphangiogenesis during tumor development. The present study evaluates whether endogenous PGE(2) exhibits a critical role in tumor-associated lymphangiogenesis.