Diagnosis of a Primary Pleomorphic Liposarcoma in a Tree Shrew（Tupaia belangeri subsp. yaoshanensis） / 实验动物与比较医学

A large spontaneous mass on the dorsal abdomen near the hip joint was found in an aged female Tupaia belangeri subsp. yaoshanensis after 5 years of routine feeding. The tumor in the diseased tree shrew was huge, with an intact surface and no ulceration; however, it caused inconvenience in movement while maintaining a good mental state. After inhalation anesthesia with isoflurane (2%-4%), the tree shrew was euthanized after the tree shrew entered deep anesthesia. Anatomical dissection of the tumor, the tumor boundary was unclear and infiltrated into surrounding tissues. HE staining showed that small focal pleomorphism and large areas of adipocytes were seen in the tumor tissue. The pleomorphic sarcoma area was mainly composed of atypical epithelioid cells with easily visible nuclear divisions. The size of the adipocytes was significantly different, and more pleomorphic adipocytes were seen. The cell volume was large, the nucleus was deeply stained and deformed, the edge was impressed, and the cytoplasm was seen with multiple vesicular lipid droplets. Immunohistochemical results showed that the tumor cells were positive for Vimentin, the small focal polymorphic adipocyte nucleus was positive for S-100, and Ki-67 exhibited a higher proportion of positivity. Combined with HE staining and immunohistochemical results, the spontaneous tumor in this tree shrew was comprehensively diagnosed as pleomorphic liposarcoma.

Diagnosis of Trichoepithelioma in a Tree Shrew and Observation of Cell Biological Characteristics / 实验动物与比较医学

ObjectiveTo observe the primary tumor of tree shrews and to provide a basis for studying the pathogenesis and prevention of trichoepithelioma. MethodsA tumor was discovered in the chest and abdomen of a tree shrew during natural cultivation. The tree shrew was anesthetized, and the tumor was surgically removed. Hematoxylin and eosin (HE) staining and immunohistochemical staining were performed on the tumor tissue after paraffin section, and the tumor cells were isolated and cultured by passage. The isolated tumor cells were subcutaneously injected into healthy tree shrews and nude mice. The tumorigenesis of tumor cells in vivo was observed once a day, with nude mice continuously observed for 2 months and tree shrews observed for more than 6 months. ResultsHE staining showed that the basal cells in the dermis were arranged as a whole, like a string of petals, forming nests and stripe-like structures with clear boundaries. The observation results after magnification revealed that the tumor cells were arranged in a pallisade-like and basal pattern, with deep nuclear staining and minimal cytoplasmic. Immunohistochemical staining showed the high expression of CK protein and low proportion expression of ki-67 protein in tumor cells, as well as the high expression of vimentin and low expressions of Bcl2 and CD10 in tumor cell mesenchyme. The isolated tumor cells grew well in DMEM medium containing 10% fetal bovine serum and could be cultured by passage, but no tumor formation was observed in healthy tree shrews and nude mice inoculated with tumor cells. ConclusionCombined with the location of the tumor, overall morphology, HE staining, and immunohistochemical results, the thoracoabdominal mass of the tree shrew was diagnosed as a trichoepithelioma.

Portal vein-superior mesenteric vein resection and reconstruction during pancreaticoduodenectomy using the perivenous occlusion management strategy / 中华肝胆外科杂志

Objective:To explore the perivenous blocking management strategy for portal vein-superior mesenteric vein (PSMV) resection and reconstruction and its effect on postoperative complications in patients undergoing pancreaticoduodenectomy (PD).Methods:The data of 137 patients with pancreatic cancer treated with PD in Beijing Chaoyang Hospital Affiliated to Capital Medical University, Chaoyang Central Hospital, the Second Hospital of Chaoyang, Rizhao Central Hospital, the Second People's Hospital of Binzhou from January 2010 to December 2020 were collected. There were 83 males and 54 females with an average age of 61.8 years. There were 42 patients in the reconstruction group and 95 patients in the control group. The main intraoperative indexes and postoperative complications were compared between the two groups with the aim to review our experience in PSMV resection and reconstruction by using the perivenous blocking management strategy.Results:PD was successfully completed in 137 patients in the reconstruction group, the PSMV blocking time was 15-120 min, with a median of 30 min. The operation time 380 (330, 465) min, intraoperative blood loss 725 (500, 1000) ml, and postoperative hospital stay 21.0 (16.0, 28.0) d in the reconstruction group were significantly higher than those of control group [305 (280, 340) min, 400 (300, 500) ml and 18.0 (14.0, 24.5) d] (all P<0.05). The reoperation rate and perioperative mortality were 4.8% (2/42) and 2.4% (1/42) in the reconstruction group, while 2.1% (2/95) and 1.0% (1/95) in the control group, respectively. There was no significant difference between the two groups (both P>0.05). The incidence of pancreatic fistula, peritoneal effusion and infection, pulmonary infection of the reconstruction group was significantly higher than those of the control group ( P<0.05). There was no significant difference in the incidence of postoperative bleeding, delayed gastric emptying, biliary fistula, incision infection, reoperation between the two groups ( P>0.05). Conclusions:PSMV resection and reconstruction significantly increased the incidences of complication after PD, including pancreatic fistula, peritoneal effusion/infection and pulmonary infection. The perivenous blocking management strategy significantly promoted smooth postoperative recovery and effectively reduced morbidity rates of postoperative bleeding and mortality after PSMV resection and reconstruction in PD.