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Laparoscopic Versus Open Surgery for Advanced Gastric Cancer
Open gastrectomy is the standard surgical treatment for gastric cancer worldwide; however, laparoscopic gastrectomy is performed with increasing frequency for early gastric cancers in high-volume centers with the requisite expertise, mainly in Asia. A recent randomized trial conducted in China compared the safety and efficacy of laparoscopic versus open resection in 1056 patients with advanced gastric cancers (T2-4a, N0-3, M0). Rates of postoperative mortality and morbidity, severe morbidity, and completion of a D2 lymphadenectomy were similar in both groups; follow-up has been inadequate for meaningful assessment of oncologic outcomes. Western populations, however, may have different outcomes since surgeon experience and patient characteristics are different. Patients in Western countries are generally older, more obese, and more likely to have poorly differentiated tumors than Asian populations, which could impact successful use of laparoscopic surgery. Further trials in Western countries are required before laparoscopic surgery can be recommended for the routine treatment of all gastric cancers.
Cabozantinib in Metastatic Renal Cell Carcinoma
In an initial report from the phase III trial comparing cabozantinib with everolimus, cabozantinib significantly prolonged progression-free survival in previously treated patients with metastatic renal cell carcinoma. Updated analysis from that trial has now shown that cabozantinib significantly prolongs overall survival, and this survival data has led to its approval by the US Food and Drug Administration. However, nivolumab has a better safety profile in this setting and has the potential for durable response off treatment, while cabozantinib is associated with multiple serious toxicities. Although there are no direct comparisons, we suggest nivolumab rather than cabozantinib for patients with metastatic renal cell carcinoma who have progressed after an initial vascular endothelial growth factor (VEGF) pathway inhibitor. The formulation and dose of cabozantinib for renal cell carcinoma (Cabometyx) is different from that used for metastatic medullary thyroid cancer (Cabometriq), and the two forms of cabozantinib should not be interchanged.
Nivolumab Immunotherapy for Platinum Refractory Head and Neck Cancer
The management of advanced squamous cell carcinoma of the head and neck that is refractory to platinum-based chemotherapy is difficult, and until now no other systemic therapy has been shown to improve overall survival in this setting. In a preliminary report of a phase III clinical trial, reported as an abstract at the American Association for Cancer Research 2016 meeting, immunotherapy with nivolumab, an antibody targeting programmed death receptor 1 (PD-1), significantly prolonged overall survival compared with single agent systemic therapy (methotrexate, docetaxel, or cetuximab) chosen at the discretion of the investigator. Detailed analysis of this trial and results from other ongoing randomized trials are needed to confirm the benefits of anti-PD-1 immunotherapy.
Checkpoint Inhibitor Immunotherapy of Merkel Cell Carcinoma
For patients with advanced Merkel cell carcinoma, systemic chemotherapy as used in other small cell carcinomas has been the only available treatment option. In a phase II study, checkpoint inhibitor immunotherapy with pembrolizumab, a programmed cell death protein 1 (PD-1) pathway blocker, yielded a 56 percent response rate and the six-month progression free survival rate was 67 percent. Although similar response rates have been reported with cytotoxic chemotherapy, the duration of disease control was substantially longer with immunotherapy. Immunotherapy with a PD-1 pathway blocker is an appropriate alternative to systemic chemotherapy, although it preferably should be administered in the context of a formal clinical trial. Use of pembrolizumab for advanced Merkel cell carcinoma is not currently approved by the Food and Drug Administration in the United States.
Underutilization of Pancreatic Enzyme Replacement Therapy in Advanced Pancreatic Cancer
Patients with advanced pancreatic cancer often have extreme weight loss, and one contributory factor is pancreatic exocrine insufficiency, which leads to maldigestion, fat malabsorption, steatorrhea, and weight loss. Despite recommendations from expert groups that patients who are suspected of having fat malabsorption should be treated empirically with oral pancreatic enzyme replacement therapy (PERT), the available evidence suggests that PERT is underutilized. In a review of 129 patients with metastatic pancreatic cancer who were referred to a specialist palliative care service in Australia, over 70 percent had symptoms that could be attributed to malabsorption (abdominal pain, bloating, gaseousness and steatorrhea), yet only 21 percent were prescribed PERT.