Pancreatic leiomyosarcoma: a diagnostic challenge and literature review

Pancreatic leiomyosarcoma in a domestic shorthair cat

Case summary

A 7-year-old female neutered domestic shorthair cat was presented with weight loss, abdominal distension, lethargy, pyrexia and hyporexia. Haematology and biochemistry were unremarkable. Abdominal ultrasound revealed a cystic mass within the left cranial abdominal quadrant, adjacent to the pancreas, stomach and spleen. CT revealed a 10.5 cm, rounded, well-encapsulated, hypodense mass arising from the left pancreatic lobe. The remaining organs of the abdominal and thoracic cavity were unremarkable. A partial left lobe pancreatectomy and splenic lymph node removal were performed. Histopathology of the pancreatic mass reported a proliferating population of neoplastic spindle cells most consistent with a preliminary diagnosis of soft tissue sarcoma. Immunohistochemistry characteristics, together with the morphological findings, were consistent with a diagnosis of leiomyosarcoma. The patient recovered without any concerns after receiving routine postoperative care. Clinical examination and abdominal ultrasound 5 months postoperatively revealed no abnormalities.

Relevance and novel information

To our knowledge, this is the first report of pancreatic leiomyosarcoma in a cat. Pancreatic leiomyosarcoma should be considered as one of the possible differential diagnoses for cats presenting with a pancreatic mass.

Malignant biliary obstruction due to metastatic non-hepato-pancreato-biliary cancer

Malignant biliary obstruction generally results from primary malignancies of the pancreatic head, bile duct, gallbladder, liver, and ampulla of Vater. Metastatic lesions from other primaries to these organs or nearby lymph nodes are rarer causes of biliary obstruction. The most common primaries include renal cancer, lung cancer, gastric cancer, colorectal cancer, breast cancer, lymphoma, and melanoma. They may be difficult to differentiate from primary hepato-pancreato-biliary cancer based on imaging studies, or even on biopsy. There is also no consensus on the optimal method of treatment, including the feasibility and effectiveness of endoscopic intervention or surgery. A thorough review of the literature on pancreato-biliary metastases and malignant biliary obstruction due to metastatic non-hepato-pancreato-biliary cancer is presented. The diagnostic modality and clinical characteristics may differ significantly depending on the type of primary cancer. Different primaries also cause malignant biliary obstruction in different ways, including direct invasion, pancreatic or biliary metastasis, hilar lymph node metastasis, liver metastasis, and peritoneal carcinomatosis. Metastasectomy may hold promise for some types of pancreato-biliary metastases. This review aims to elucidate the current knowledge in this area, which has received sparse attention in the past. The aging population, advances in diagnostic imaging, and improved treatment options may lead to an increase in these rare occurrences going forward.

Pancreatic Leiomyosarcoma With Schistosomiasis Hematobia: A Case Report and Literature Review

Pancreatic leiomyosarcoma (PL) is a very rare, malignant neoplasm with a very poor prognosis. Here, we examine a novel case of PL with schistosomiasis hematobia. The patient had been initially misdiagnosed by the first magnetic resonance imaging (MRI). The second imaging examination demonstrated an enlarged heterogeneous tumor mass in the body-tail of pancreas. Following image analysis, the patient underwent a pancreatectomy, splenectomy and lymph node dissections. Sixteen months after the tumor resection, follow-up computed tomography (CT) and MRI revealed tumor metastasis in the liver and lung. PL has non-specific clinical manifestations and imaging characteristics, making early diagnosis very challenging. When it is difficult to distinguish between benign and malignant pancreatic lesions, short-term imaging follow-up is preferred. In this case report, we discuss the relationship between PL and schistosomiasis hematobia.