Role of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in the treatment of gastric cancer.

Patients with peritoneal carcinomatosis (PC) of gastric origin have a poor prognosis of life with an average survival of 1-3 months. Systemic chemotherapy has improved the survival of those patients with gastric metastatic cancer at 7-10 months. However, this benefit could not be reproduced in those patients with PC. The current literature for the use of hyperthermic intraperitoneal chemotherapy (HIPEC) for gastric PC has significant variation related to patient selection, treatment intent (palliative vs. attempt at curative treatment), surgical technique, intraperitoneal chemotherapy agent utilized, and systemic chemotherapy administered adjuvantly. From the perspective of patient selection for cytoreduction and HIPEC, patients with extensive PC are not candidates. In addition, unresectable location would make a patient a poor candidate for cytoreduction and HIPEC. Optimally, those with positive peritoneal cytology alone could benefit most. However, the role of cytoreductive surgery and HIPEC in patients with PC of gastric origin has not yet been clarified.

Los pacientes con carcinomatosis peritoneal (CP) de origen gástrico tienen un mal pronóstico de vida, con una supervivencia media de 1 a 3 meses. La quimioterapia sistémica ha mejorado la supervivencia de los pacientes con cáncer gástrico metastásico a los 7-10 meses. Sin embargo, este beneficio no se ha podido reproducir en los pacientes con CP. En cuanto a lo relacionado con la literatura actual para el uso de HIPEC (hyperthermic intraperitoneal chemotherapy) en la CP de origen gástrico, existe una variación significativa en la selección de pacientes, la intención de tratamiento (paliativo frente a intento de tratamiento curativo), la técnica quirúrgica, el agente quimioterapéutico intraperitoneal utilizado y la quimioterapia sistémica adyuvante administrada. Desde la perspectiva de la selección de pacientes para citorreducción y tratamiento con HIPEC, los pacientes con CP extensa no son candidatos. Además, lesiones irresecables por su localización harían al paciente un pobre candidato para citorreducción y tratamiento con HIPEC. De manera óptima, aquellos pacientes con citología peritoneal positiva en ausencia de CP son quienes más podrían beneficiarse. Sin embargo, el papel de la cirugía citorreductora y del tratamiento con HIPEC en los pacientes con CP de origen gástrico aún no ha sido esclarecido.

Primary retroperitoneal Merkel cell carcinoma: Case report and literature review.

BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma that affects elderly patients and typically arises in sun-exposed skin. The disease is very rare and only few cases present with no apparent skin lesion. In the retroperitoneum there are only two cases reported in the literature. CASE PRESENTATION: We report a case of a 54-year-old Mexican male with MCC, which presented as a large retroperitoneal mass. Pathological and immunohistochemical analysis of the transabdominal CT-guided biopsy specimen revealed a MCC. The patient underwent preoperative chemotherapy followed by a laparotomy and the mass was successfully excised. DISCUSSION: There are two possible explanations for what occurred in our patient. The most plausible theory is the retroperitoneal mass could be a massively enlarged lymph node where precursor cells became neoplastic. This would be consistent with a presumptive diagnosis of primary nodal disease. Moreover, metastasis to the retroperitoneal lymph nodes has been reported as relatively common when compared to other sites such as liver, bone, brain and skin. The less probable theory is the non-described "regression" phenomena of a cutaneous MCC, but we are not found a primary skin lesion. CONCLUSION: Preoperative chemotherapy and excision of the primary tumor is the surgical treatment of choice for retroperitoneal MCC. We propose that further studies are needed to elucidate the true efficacy of chemotherapy in conventional and unconventional patients with MCC.