[Successful Long-Term Treatment with Intermittent Oxaliplatin Administration for Recurrent Sigmoid Colon Cancer without Developing Neuropathy].

We report a case ofrecurrent sigmoid cancer in which long-term disease control was achieved by intermittent oxaliplatin (L-OHP)administration. A 58-year-old woman underwent first-line chemotherapy with capecitabine and L-OHP(CapeOX) following peritoneal lymph node recurrence of sigmoid cancer. Tumor shrinkage was confirmed by a computed tomography (CT)scan following 4 courses of CapeOX treatment. However, L-OHP administration was discontinued by the 9 course due to peritoneal neuropathy. L-OHP was reintroduced following tumor progression confirmed by CT or elevation of carcinoembryonic antigen levels detected by a blood test. This stop-and-go strategy controlled lymph node recurrence effectively for over 5 years and was not associated with the development ofperitoneal neuropathy. We suggest that the intermittent administration ofL -OHP-containing chemotherapy is an important treatment option for some patients with advanced colorectal cancer, achieving effective long-term disease control with no associated peripheral neuropathy.

[Efficacy of low-dose erlotinib against gefitinib-induced hepatotoxicity in a patient with lung adenocarcinoma harboring EGFR mutations].

We report a case of a female in her 80s who was diagnosed with recurrent lung adenocarcinoma after primary surgery. She was treated with a systemic chemotherapy regimen consisting of carboplatin plus paclitaxel until the disease showed progression. On detection of epidermal growth factor receptor(EGFR)mutations, we administered gefitinib, an EGFR tyrosine kinase inhibitor, at a dosage of 250 mg daily. After 6 months of gefitinib therapy, laboratory findings revealed elevated serum aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels(grade 2), indicative of hepatotoxicity. Gefitinib was discontinued and erlotinib was initiated at a dosage of 50 mg daily. She continued the therapy for 3 years, during which her disease stabilized without any further complications or hepatotoxicity. Thus, low-dose erlotinib may be effective and well tolerated by patients with non-small cell lung cancer harboring EGFR mutations who are intolerant to gefitinib.

[A case of colon cancer with chronic renal dysfunction responding to effective retreatment with FOLFIRI].

A 76-year-old man with renal dysfunction received FOLFIRI due to a relapse in his pelvis after surgery for sigmoid colon cancer. FOLFIRI was continued for approximately 21 months with stabilization of disease observed on CT scans, but his tumor marker levels increased and tumors showed progression. He then began treatment with cetuximab/CPT-11, but disease progression was observed. XELOX in a low-dose was then administered, but this therapy was discontinued because of progression. He could not receive the other antitumor agents, due to mutations of the KRAS gene and renal dysfunction. Therefore, FOLFIRI was restarted, because it can be continued for long periods of time. Consequently, his tumor marker levels decreased with stabilization of disease on CT scans, and he continued the therapy for 7 months while maintaining quality of life. Ultimately, this case suggested that if there was effectiveness from a previous treatment, retreatment would be successful as chemotherapy for colon cancer in the difficult situation of selecting the other effective antitumor agents.

A case of advanced pancreatic neuroendocrine tumor in which octreotide long-acting repeatable was effective after failure of everolimus and sunitinib.

Molecular targeted drugs, such as everolimus and sunitinib, have shown efficacy against advanced pancreatic neuroendocrine tumors. Octreotide, a somatostatin analogue, improves the hormone-related symptoms in patients with neuroendocrine tumors. Furthermore, it has been reported that octreotide has antitumor activity in patients with metastatic midgut neuroendocrine tumors. However, whether octreotide has anti-proliferative effects in patients with advanced pancreatic neuroendocrine tumors is not fully understood. We report a 71-year-old man with multiple liver metastases of pancreatic neuroendocrine tumor. He was treated with everolimus 10 mg daily and sunitinib 25 mg daily on days 1-14 every 3 weeks at the physician's discretion. However, these molecular targeted drugs were discontinued due to disease progression or severe adverse effects. Octreotide long-acting repeatable was administered continuously from the initiation of everolimus treatment. The tumor marker level markedly decreased and the metastatic liver lesions showed shrinkage with octreotide treatment. Immunohistochemistry of tumor specimens obtained before treatment showed that somatostatin receptor 2, a high-affinity receptor for octreotide, was highly expressed. The clinical course of this patient suggested that octreotide long-acting repeatable may be a treatment option for advanced pancreatic neuroendocrine tumors after failure of everolimus and sunitinib. Further clinical trials are warranted to determine whether the expression of somatostatin receptor 2 in tumor tissues is predictive of octreotide efficacy.

Elevated prothrombin time/international normalized ratio associated with concurrent administration of regorafenib and warfarin in a patient with advanced colorectal cancer.

BACKGROUND: Regorafenib and its metabolites may inhibit the activities of several CYP or UDP-glucuronosyltransferase isoforms, including that of CYP2C9. Therefore, pharmacological agents that are CYP2C9 substrates may show elevated circulating levels and enhanced drug efficacy when concurrently used with regorafenib. Previous studies showed that the area under the plasma concentration-time curve of warfarin, which is the substrate for CYP2C9, increased upon co-administration of regorafenib. However, there are no reports indicating that the anticoagulant effects of warfarin increased upon co-administration of regorafenib. CASE PRESENTATION: We report a case of a 76-year-old man with liver metastasis of colon cancer. He was treated with regorafenib at a dosage of 120 mg daily on days 1 to 21 every 4 weeks as a third-line therapy. He had a history of acute myocardial infarction and had taken 2 mg warfarin daily. Three weeks after the treatment began, PT/INR values markedly increased, although there was no hemorrhage. Administration of regorafenib and warfarin was discontinued, and then PT/INR rapidly decreased. Warfarin administration was restarted (0.5 mg daily) and the dose was increased up to 1.5 mg daily. The patient's PT/INR values exhibited a tendency to increase when concurrently used with regorafenib, the dose of which was reduced to 80 mg daily on days 1 to 14 every 3 weeks at a physician's discretion. CONCLUSIONS: The clinical course of this patient suggested that PT/INR might increase during concurrent use of warfarin and regorafenib. Therefore, PT/INR should be periodically monitored during the concurrent use of warfarin and regorafenib.