Pulmonary tumor thrombotic microangiopathy with thrombus in pulmonary artery caused by diffuse sclerosing variant of thyroid papillary adenocarcinoma: A case report.

Pulmonary tumor thrombotic microangiopathy (PTTM) is a fatal disease associated with malignant tumors that progresses to pulmonary hypertension. Gastric cancer is the most common cause, followed by breast cancer and lung cancer, whereas PTTM due to thyroid cancer has not been reported. In addition to pulmonary obstruction by tumor embolism, tumor cells stimulate endothelial cells to release angiogenetic factors, which induce remodeling of pulmonary arteries and veins and lead to lymphatic obstruction. There is limited information on the relationship between thrombus and PTTM. We herein report an autopsy case with PTTM which was caused by diffuse sclerosing variant of thyroid papillary adenocarcinoma, in which differential diagnosis included the acute phase of chronic thromboembolic pulmonary hypertension.

Amelanotic Malignant Melanoma with a BRAF V600E Mutation Mimicking Primary Lung Cancer.

Amelanotic melanoma is a rare type of melanoma that shows little or no melanin pigmentation. When tumor lesions are not detected in cutaneous sites, the presence of melanin is the hallmark sign of malignant melanoma. We herein report a case of amelanotic melanoma with a BRAF V600E mutation mimicking primary lung cancer that was finally diagnosed on an autopsy. The current case suggests important caveats for the differential diagnosis of patients with BRAF V600E mutation-positive poorly differentiated lung tumors. In terms of the pathological diagnosis, routine immunohistochemical staining may be useful, especially in patients with a poorly differentiated lung tumor without TTF-1 expression.

Association of peripheral blood neutrophil gelatinase-associated lipocalin levels with bone marrow neutrophil gelatinase-associated lipocalin levels and neutrophil count in hematologic malignancy.

BACKGROUND: Although neutrophil gelatinase-associated lipocalin (NGAL) is a biomarker for acute kidney injury, recently, high NGAL levels have been reported in hematologic malignancies. Given the mechanism underlying NGAL synthesis and secretion in neutrophilic series, it is speculated that NGAL levels are higher in bone marrow (BM) than in peripheral blood (PB). Additionally, PB NGAL levels are thought to be associated with neutrophilic parameters. We aimed to test both hypotheses in hematologic malignancies. METHODS: Paired BM and PB samples were collected from 41 patients undergoing BM examination for hematologic malignancies. NGAL levels were measured using immunoassays. Data on hematologic parameters were collected from medical records. Single and multiple regression analyses were performed to analyze the relationship. RESULTS: PB and BM NGAL (n = 41) levels were significantly different (163.0 ± 258.3 and 413.1 ± 616.2 ng/mL [mean ± standard deviation], respectively; P < 0.05). Simple regression analysis and multicollinearity assessment showed that BM NGAL levels, BM neutrophil%, and neutrophil count were significant predictors of PB NGAL. Two multiple regression models were developed (model 1, PB NGAL = 21.467* neutrophil count - 0.785*BM neutrophil%; model 2, PB NGAL = 21.202*neutrophil count- 0.915*BM neutrophil% +0.10*BM NGAL). Akaike's information criterion and adjusted R2 values showed that model 1 had higher predictive accuracy for PB NGAL. In both models, neutrophil count was the only significant predictor. CONCLUSION: BM NGAL was significantly higher than PB NGAL in hematologic malignancy. In addition, PB NGAL could be expressed as a multiple regression model including neutrophil count and BM neutrophil%, being significantly influenced by neutrophil count.