Mixed Adenoneuroendocrine Carcinoma of the Esophagus: A Case Report and Review of the Literature.

The most frequent presentation of esophageal cancer is adenocarcinoma and squamous cell carcinoma. In recent years, the latter has decreased its incidence increasing the adenocarcinoma. Currently, another type of tumor with a much lower incidence has been described, which has a neuroendocrine component along with another exocrine glandular component and has been classified since 2010 as mixed adenoneuroendocrine carcinoma (MANEC). We present the case of a 68-year-old male with a history of dyspepsia and epigastric pain who after performing a gastroscopy, was diagnosed with a malignant neoplasm of the esophagus. The patient underwent a total esophagectomy with reconstruction by tubular gastroplasty with cervical anastomosis. The final result of the piece after immunohistochemistry revealed that the tumor was composed of one component of adenocarcinoma in 60% together with another component compatible with neuroendocrine in 40%. With these findings and according to the World Health Organization classification of 2010 was diagnosed as esophageal MANEC. MANECs are rare tumors, described in other locations of the digestive tract, the esophagus being an infrequent location. Its preoperative diagnosis is difficult, and it is not until the final analysis of the complete piece by means of specific immunohistochemical techniques when its diagnosis can be established. Its treatment is fundamentally surgical, whereas the adjuvant therapeutic schemes with chemotherapy are not well defined at present because of their low incidence.

Life-supporting human complement regulator decay accelerating factor transgenic pig liver xenograft maintains the metabolic function and coagulation in the nonhuman primate for up to 8 days.

BACKGROUND: It is not known whether the pig liver is capable of functioning efficiently when transplanted into a primate, neither is there experience in transplanting a liver from a transgenic pigs expressing the human complement regulator human complement regulator decay accelerating factor (h-DAF) into a baboon. The objective of this study was to determine whether the porcine liver would support the metabolic functions of non-human primates and to establish the effect of hDAF expression in the prevention of hyperacute rejection of porcine livers transplanted into primates. METHODS: Five orthotopic liver xenotransplants from pig to baboon were carried out: three from unmodified pigs and two using livers from h-DAF transgenic pigs. FINDINGS: The three control animals transplanted with livers from unmodified pigs survived for less than 12 hr. Baboons transplanted with livers from h-DAF transgenic pigs survived for 4 and 8 days. Hyperacute rejection was not detected in the baboons transplanted with hDAF transgenic pig livers; however, it was demonstrated in the three transplants from unmodified pigs. Baboons transplanted with livers from h-DAF transgenic pigs were extubated at postoperative day 1 and were awake and able to eat and drink. In the recipients of hDAF transgenic pig livers the clotting parameters reached nearly normal levels at day 2 after transplantation and remained normal up to the end of the experiments. In these hDAF liver recipients, porcine fibrinogen was first detected in the baboon plasma 2 hr postreperfusion, and was present up to the end of the experiments. One animal was euthanized at day 8 after development of sepsis and coagulopathy, the other animal arrested at day 4, after an episode of vomiting and aspiration. The postmortem examination of the hDAF transgenic liver xenografts did not demonstrate rejection. INTERPRETATION: The livers from h-DAF transgenic pigs did not undergo hyperacute rejection after orthotopic xenotransplantation in baboons. When HAR is abrogated, the porcine liver maintains sufficient coagulation and protein levels in the baboon up to 8 days after OLT.