Histopathological predictors of regional lymph node metastasis at the invasive front in early colorectal cancer.

AIMS: In early colorectal cancer (ECC), prediction of lymph node (LN) metastasis is vital for the decision of additional surgical treatment after endoscopic mucosal/submucosal resection. The aim of this study was to determine the relationship between LN metastasis and comprehensive histopathological findings including the cancer microenvironment in ECC. METHODS AND RESULTS: Using 111 ECC cases, including 36 cases with LN metastasis, histopathological observations and immunohistochemistry for lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), von Willebrand factor, matrix metalloproteinase-7 (MMP-7), CXC chemokine ligand-12 (CXCL12) and angiopoietin-like-4 (ANGPTL4) were conducted. Relationships between LN metastasis and growth pattern, status of muscularis mucosae, depth of cancer invasion, overall histopathological type, histopathological type at the invasive front, tumour budding, neutrophil infiltration in cancer cells (NIC), fibrotic cancer-stroma type, Crohn's-like lymphoid reaction, microscopic abscess formation and lymphatic invasion were determined. In addition, the expression of MMP-7, CXCL12 and ANGPTL4 in cancer cells at the invasive front were also considered in the context of LN metastasis. By multivariate analysis, lymphatic invasion, NIC and MMP-7 expression at the invasive front were independent predictors of LN metastasis. CONCLUSIONS: LN metastasis is regulated not only by the characteristics of cancer cells but also by microenvironmental factors of lymphatics and neutrophils, especially at the invasive front.

[Coinfection with Pneumocystis jirovecii and Mycobacterium tuberculosis in a patient with AIDS: a first report in Japan].

A 24-year-old man was admitted with a 7-month history of non-productive cough, and recent onset of fever and progressive dyspnea. A chest X-ray film and computed tomography (CT) scan showed bilateral infiltrates that indicated pneumocystis pneumonia (PCP). A transbronchial lung biopsy specimen demonstrated Pneumocystis jirovecii infection on Grocott staining, and was positive for acid-fast bacilli without necrotizing granuloma, which indicated coinfection with both Pneumocystis jirovecii and Mycobacterium tuberculosis. A test for human immunodeficiency virus (HIV) infection was positive, and his CD4 + T-lymphocyte count was 92 cells per cubic millimeter. Chest CT findings and pathological findings.were atypical for active tuberculosis (TB). It is important that clinicians should be aware that HIV-infected patients may have concurrent pulmonary TB and PCP, because the diagnosis is difficult.

Anatomic properties of myocardial bridge predisposing to myocardial infarction.

BACKGROUND: A myocardial bridge (MB) that partially covers the course of the left anterior descending coronary artery (LAD) sometimes causes myocardial ischemia, primarily because of hemodynamic deterioration, but without atherosclerosis. However, the mechanism of occurrence of myocardial infarction (MI) as a result of an MB in patients with spontaneously developing atherosclerosis is unclear. METHODS AND RESULTS: One hundred consecutive autopsied MI hearts either with MBs [MI(+)MB(+) group; n=46] or without MBs (n=54) were obtained, as were 200 normal hearts, 100 with MBs [MI(-)MB(+) group] and 100 without MBs. By microscopy on LADs that were consecutively cross-sectioned at 5-mm intervals, the extent and distribution of LAD atherosclerosis were investigated histomorphometrically in conjunction with the anatomic properties of the MB, such as its thickness, length, and location and the MB muscle index (MB thickness multiplied by MB length), according to MI and MB status. In the MI(+)MB(+) group, the MB showed a significantly greater thickness and greater MB muscle index (P<0.05) than in the MI(-)MB(+) group. The intima-media ratio (intimal area/medial area) within 1.0 cm of the left coronary ostium was also greater (P<0.05) in the MI(+)MB(+) group than in the other groups. In addition, in the MI(+)MB(+) group, the location of the segment that exhibited the greatest intima-media ratio in the LAD proximal to the MB correlated significantly (P<0.001) with the location of the MB entrance, and furthermore, atherosclerosis progression in the LAD proximal to the MB was largest at 2.0 cm from the MB entrance. CONCLUSIONS: In the proximal LAD with an MB, MB muscle index is associated with a shift of coronary disease more proximally, an effect that may increase the risk of MI.