Clinicopathological Characteristics of Cancer-Associated Venous Thromboembolism (CAT-VTE) from a Medicolegal Autopsy.

Objective: This study aimed to determine the clinicopathological characteristics of cancer-associated venous thromboembolism (CAT-VTE). Methods: A total of 47 cases of lethal pulmonary thromboembolism (PTE) with active cancer were investigated by autopsy records. Results: We studied 22 men and 25 women who were deceased at a mean age of 66±11 years. Nine (19%) patients had recently undergone cancer resection, 14 (30%) were undergoing clinical treatment for cancer, and 24 (51%) were autopsy-proven CAT-VTE. The colon (eight cases), lungs (seven cases), and ovaries (six cases) were frequent sites of a tumor. There were 29 (62%) cases of acute PTE and 18 (38%) of recurrent PTE. The embolic source was detected in 36/39 (92%) cases. Among them, 33 cases were leg deep vein thrombosis (DVT) and 31 were calf-type DVT. Three cases were isolated vena cava thrombi that were present near the tumor. Twenty-three (64%) cases were recurrent DVT. Conclusion: Most of the lethal CAT-VTE cases were induced by the same mechanism as non-CAT-VTE that originated from calf-type DVT with proximal propagation. However, the finding that patients had tumor-related vena cava thrombi suggested that prevention of CAT-VTE requires individualized treatment of patients according to their pathological condition. (This is secondary publication from Jpn J Phlebol 2020; 31(3): 123-129.).

An autopsy case of pulmonary artery intimal sarcoma: detailed observation of tumor and its related lesions in pulmonary arteries.

We report an autopsy-proven case of a 33-year-old man who died of intimal sarcoma of the pulmonary artery. A large mass (5×4 cm) occluded the main and bilateral pulmonary arteries. Tumor cell morphology was consistent with that of undifferentiated pleomorphic sarcoma. Comprehensive histological observation of 18 pulmonary arteries from proximal to distal revealed continuous extension of the tumor from the main to the subsegmental arteries along the intima, forming an arteriosclerosis-like intimal thickening. Distal small arteries were also affected by eccentric intimal thickening or recanalization. Lung parenchyma was not involved, although there were two wedge-shaped small pulmonary infarctions caused by tumorous obstruction of the associated arteries. Histological results indicated that the intimal sarcoma in the pulmonary artery, which appeared occlusive with growth limited to the proximal artery, had in fact already spread more peripherally than expected. Both the proximal lesions and the distal small arteries were affected by peripheral tumor emboli or by pulmonary hypertension induced by the proximal tumor. However, as seen in this case, most of the occlusive tumor was located locally and intraluminally, in the proximal artery, and removing the proximal tumor by pulmonary endarterectomy was considered effective for symptomatic improvement.

Abdominal Stab Wounds with Tension Pneumopericardium Confirmed by Autopsy and Postmortem Computed Tomography.

We present the first report of pneumopericardium observed by autopsy and on postmortem computed tomography (PMCT) images. The subject was a woman who died of self-inflicted stab wounds to the abdomen. The PMCT scan revealed air in the pericardial sac, a "flattened heart" sign, and retroperitoneal hemorrhage. Medicolegal autopsy revealed two abdominal stab wounds near the xiphoid process that had cut the apical pericardium and adjacent diaphragm and liver. Examination of the open thorax confirmed that the pericardial sac was distended with air. The wound extended to the abdominal aorta, causing retroperitoneal hemorrhage. PMCT images showed that the pneumopericardial volume was 133 mL. We believe that cardiac tamponade occurred resulting from the tension pneumopericardium; however, the effects were mitigated by hypovolemia secondary to the retroperitoneal hemorrhage as well as obstructive shock. Therefore, the cause of death appears to have been low-pressure cardiac tamponade.

Two autopsy cases of rupture of the aorta by fistula formation after thoracic endovascular aortic repair and open stent-grafting on aortic arch aneurysm.

The mortality rate of aortic aneurysm/dissection is low in Japan. Two surgical procedures, the thoracic endovascular aortic repair (TEVAR) and the open stent-grafting have contributed much in survival of such aneurysmal patients. We encountered with two autopsy cases of death by aortic rupture with fistula formation after these procedures. Case 1 is an 85-year-old male who had the history of TEVAR for thoracic aorta aneurysm one and a half year before his death. His endovascular stent-graft was composed of a steel endoskeleton consisting of six Z-shape elements while at autopsy, one of the elements locating at the distal part was found inserted deep into the wall of descending aorta, causing aorto-esophageal fistula. Case 2 is an 88-year-old male who had the history of open stent-grafting for aortic aneurysm eight years ago. At autopsy, the stent-graft was found detached from aorta at its lesser curvature, causing gap formation between the aorta and the stent. Six Z-shaped stent elements, the parts of stent-graft, were found separated from descending aorta and located in the aneurism. Furthermore, three of the separated elements were found inserted deep in the aortic wall, causing aorto-pulmonary fistula. Since aorto-esophageal fistula formation after surgery for aortic aneurysm is very rare in TEVAR and there are no reported cases of death by aorto-pulmonary fistula in the open stent-grafting, these cases are reported here.

Cellular uptake of paraquat determines subsequent toxicity including mitochondrial damage in lung epithelial cells.

Paraquat (PQ) is one of the commonly used herbicides in the world, despite its high toxicity. The ingestion of PQ accidentally or intentionally causes severe damage in diverse organs including the lung. Pulmonary fibrosis triggered by PQ accumulation in the lung epithelial cells is one of the major causes of death. This study investigated the intracellular accumulation of PQ, reactive oxygen species (ROS) generation and mitochondrial injury using two lung epithelial cell lines A549 and BEAS-2B (BEAS). Although A549 exhibit greater resistance to oxidative stress than BEAS, a cytotoxicity assay for PQ demonstrated that EC50 for lethality in A549 was 7 times lower than that in BEAS. When exposed to PQ at a concentration around EC50 for lethality, the amount of ROS generated in A549 was as low as that in BEAS. Conversely, the cellular concentration of PQ in A549 after exposure was higher than that in BEAS, which suggests a distinct difference in the susceptibility to PQ between these cell lines. After a 16 h exposure to PQ, mitochondrial membrane potential (MMP) decreased in A549, but decreased only slightly in BEAS even following a 30 h exposure. PQ-exposed A549 reduced an accumulation of PTEN-induced kinase 1 (PINK1), which works in degradation of damaged mitochondria, following the decrease of MMP, whereas PQ did not decline the PINK1 in BEAS. These results suggest that mitochondrial dysfunction due to cellular accumulation of PQ might contribute to the PQ-provoked toxicity more than the ROS generation in the lung epithelial cells.

Fatal vascular injury as a result of operations: experience of two surgery-related autopsies.

We experienced two autopsy cases of unexpected death during surgical operation. Case 1 was a 60-year-old male. Salvage esophagectomy was performed from the right side of the thrax. After dissection of the lymph node, blood pressure decreased suddenly. Emergency thoracotomy was done for diffuse hemothorax in the left thoracic cavity. The patient died despite aggressive hemostasis. Autopsy findings revealed that the operator dissected the left subclavian artery instead of the lymph nodes. Case 2 was a 60-year-old male with advanced thyroid cancer with pelvic metastasis. Surgical removal of the sacrum was attempted for pain relief. The operation was interrupted because of massive hemorrhage from the iliac veins. After the operation, the patient's left leg quickly became necrotic. Despite the bypass grafting from the right to the left femoral artery, the patient died of reperfusion injury. Autopsy revealed ligation of the left common iliac artery along with the accompanying vein. The leg necrosis was thought to have resulted from the vascular ligation. In these two cases, the demonstration and elucidation of the causes of deaths were required with medicolegal autopsies. However, it proved difficult to visualize the operated vessels in detail. In autopsy investigations related to surgical operations, detailed information of the clinical course is valuable and should be provided by the operators themselves, as well as being obtained from clinical charts.