American Journal of Surgical Pathology最新文献

Differences in risk factors (RF) of lymph node metastasis (LNM) and prognosis between submucosal early gastric cardiac (SEGCC) and noncardiac (SEGNCC) carcinomas remain unclear. In this study, we investigated and compared RF of LNM and prognosis in 891 patients with radical gastrectomy for SEGCC (n=217) or SEGNCC (n=674). Compared with SEGNCC, SEGCC displayed significantly higher proportion of elderly patients (70 y or above), the elevated macroscopic type, well/moderately differentiated tubular and low-grade papillary adenocarcinomas, as well as low-grade tumor budding, but lower prevalence of the depressed macroscopic type, poorly differentiated tubular adenocarcinoma, mixed adenocarcinoma, poorly cohesive carcinoma, lymphovascular invasion (LVI), perineural invasion, and high-grade tumor budding. By univariate analysis, significant RF for LNM of the cohort included female sex, poor differentiation, SM2 invasion, LVI, intermediate-grade and high-grade tumor budding, whereas tumor size, histology type, and perineural invasion were the significant RF for LNM in SEGNCC. By multivariate analysis, significant independent RF for LNM included female sex and LVI in SEGCC but were female sex, mixed adenocarcinoma, LVI, and high-grade tumor budding in SEGNCC. The 5-year overall survival was significantly worse in SEGCC than in SEGNCC for patients with LNM, but not for those without. For overall survival, LNM was the only significant independent RF in SEGCC, whereas age 70 years or above and LNM were independent RF in SEGNCC. The results of our study provided the clinicopathologic evidence for individualized clinical management strategies for these 2 groups of patients and suggested different pathogenesis mechanisms between SEGCC and SEGNCC.

A distinctive histological variant of poorly differentiated, sarcomatoid, non-small cell lung carcinoma characterized by a discohesive population of giant tumor cells associated with prominent interstitial inflammatory cell infiltrates is described. The tumors occurred in 7 women and 7 men, 42 to 72 years of age (mean: 56 y). They predominantly affected the upper lobes and measured 1.3 to 9 cm in greatest diameter (mean: 4.6 cm). The tumor cells were characterized by large pleomorphic nuclei with prominent nucleoli, ample cytoplasm, and frequent abnormal mitoses, and were surrounded by a dense inflammatory cell infiltrate, often associated with emperipolesis. Immunohistochemical stains were positive in the tumor cells for cytokeratin AE1/AE3 and CK8/18 and negative for TTF1, napsin A, p40, and CK5/6. Next-generation sequencing was performed in all cases using the Oncomine Precision Assay; the most common abnormalities found included TP53 mutations (9 cases) and AKT1 amplification (8 cases), followed by KRAS mutations (4 cases) and MAP2K1/2 mutations (4 cases). Clinical follow-up was available in 13 patients. Three patients presented with metastases as the initial manifestation of disease; 8 patients died of their tumors from 6 months to 8 years (mean: 2.7 y); 3 patients were alive and well from 4 to 6 years; and 2 patients had metastases when last seen but were lost to follow-up thereafter. The importance of recognizing this distinctive and aggressive variant of non-small cell lung carcinoma lies in avoiding confusion with a sarcoma or other types of malignancy.

Pulmonary complications continue to cause significant morbidity and mortality in posthematopoietic stem cell transplantation (HSCT) settings. The histopathology of pulmonary diseases in the post-HSCT context is poorly characterized, especially in the pediatric population. We sought to characterize the pathologic spectrum of pulmonary disease post-HSCT in a pediatric cohort. Fifty-six specimens, including 53 biopsy specimens, corresponding to 53 patients, were identified. Biopsy slides were reviewed and assigned to diagnostic categories (infectious, graft-versus-host disease, vasculopathy, indeterminate, and others) by consensus among 3 pediatric pulmonary pathologists, taking into consideration pathologic, clinical, radiologic, and laboratory findings. The most common diagnostic category was infection (n=20). Vasculopathy, mostly in the form of fibromyxoid intimal expansion, was very common in the entire cohort (n=26) and was the sole finding in a small subset of patients (n=5), with particularly poor outcomes. A subset of biopsies remained indeterminate (n=10), and the findings in this cohort were dominated by acute lung injury. The latter group had a poor prognosis, with a short biopsy-to-death interval. The overall clinicopathologic concordance was 40%, most commonly agreeing in the infectious category. Finally, wedge biopsies led to a change in management in 69% of cases versus 23% of limited procedures (i.e., core needle biopsies). Our results suggest that while infectious complications continue to be common post-HSCT, other findings such as vasculopathy and acute lung injury portend a particularly poor prognosis and should be actively sought and reported.

GLI1 -altered mesenchymal tumor is a recently described distinct pathologic entity with an established risk of malignancy, being defined molecularly by either GLI1 gene fusions or amplifications. The clinicopathologic overlap of tumors driven by the 2 seemingly distinct mechanisms of GLI1 activation is still emerging. Herein, we report the largest series of molecularly confirmed GLI1 -altered mesenchymal neoplasms to date, including 23 GLI1- amplified and 15 GLI1 -rearranged new cases, and perform a comparative clinicopathologic, genomic, and survival investigation. GLI1- rearranged tumors occurred in younger patients (42 vs. 52 y) and were larger compared with GLI1 -amplified tumors (5.6 cm vs. 1.5 cm, respectively). Histologic features were overall similar between the 2 groups, showing a multinodular pattern and a nested architecture of epithelioid, and less commonly spindle cells, surrounded by a rich capillary network. A distinct whorling pattern was noted among 3 GLI1 -amplified tumors. Scattered pleomorphic giant cells were rarely seen in both groups. The immunoprofile showed consistent expression of CD56, with variable S100, CD10 and SMA expression. Genomically, both groups had overall low mutation burdens, with rare TP53 mutations seen only in GLI1- amplified tumors. GLI1 -amplified mesenchymal tumors exhibit mostly a single amplicon at the 12q13-15 locus, compared with dedifferentiated liposarcoma, which showed a 2-peak amplification centered around CDK4 (12q14.1) and MDM2 (12q15). GLI1 -amplified tumors had a significantly higher GLI1 mRNA expression compared with GLI1 -rearranged tumors. Survival pooled analysis of current and published cases (n=83) showed a worse overall survival in GLI1 -amplified patients, with 16% succumbing to disease compared with 1.7% in the GLI1- rearranged group. Despite comparable progression rates, GLI1 -amplified tumors had a shorter median progression-free survival compared with GLI1 -rearranged tumors (25 mo vs. 77 mo). Univariate analysis showed that traditional histologic predictors of malignancy (mitotic count ≥4/10 high-power fields, presence of necrosis, and tumor size ≥5 cm) are associated with worse prognosis among GLI1 -altered mesenchymal tumors.

Loss of S-methyl-5'-thioadenosine phosphorylase (MTAP) expression is a common event in cancer leading to a critical vulnerability of cancer cells towards anti-cancer drugs. Homozygous MTAP deletions result in a complete expression loss that can be detected by immunohistochemistry (IHC). In this study, a tissue microarray containing 17,078 samples from 149 different tumor entities was analyzed by IHC, and complete MTAP loss was validated by fluorescence in situ hybridization. MTAP loss was observed in 83 of 149 tumor categories, including neuroendocrine neoplasms (up to 80%), Hodgkin lymphoma (50.0%), mesothelioma (32.0% to 36.8%), gastro-intestinal adenocarcinoma (4.0% to 40.5%), urothelial neoplasms (10.5% to 36.7%), squamous cell carcinomas (up to 38%), and various types of sarcomas (up to 20%) and non-Hodgkin lymphomas (up to 14%). Homozygous MTAP deletion was found in 90% to 100% of cases with MTAP expression loss in most tumor categories. However, neuroendocrine tumors, Hodgkin lymphomas, and other lymphomas lacked MTAP deletions. MTAP deficiency was significantly linked to unfavorable tumor phenotype in selected tumor entities and the presence of PD-L1 expression on tumor cells, absence of PD-L1 expression on immune cells, and a low density of CD8 + lymphocytes. In summary, MTAP deficiency can occur in various tumor entities and is linked to unfavorable tumor phenotype and noninflamed tumor microenvironment, but is not always related to deletions. MTAP IHC is of considerable diagnostic value for the detection of neoplastic transformation in multiple different applications.

Carcinoma ex pleomorphic adenoma (CXPA) is an aggressive epithelial and/or myoepithelial neoplasm that arises in association with a pleomorphic adenoma (PA). Its etiopathogenesis remains poorly understood, but it is believed that the development of this tumor is due to the accumulation of genetic, protein, metabolic, and epigenetic alterations in a PA. A retrospective review of the Salivary Gland Tumor Registry in Pilsen yielded 84 CXPA, namely 25/84 salivary duct carcinoma (SDC), 15/84 myoepithelial carcinoma (MC), 1/84 epithelial-myoepithelial carcinoma (EMC), and 1/84 adenoid cystic carcinoma (AdCC). All 84 CXPA cases were analyzed by next-generation sequencing (NGS) and/or fluorescence in situ hybridization (FISH). Forty-three tumors originally diagnosed as CXPA (43/84, 51.2%) showed some molecular alteration. Fusion transcripts were identified in 12/16 (75%) CXPA, including LIFR::PLAG1, CTNNB1::PLAG1, FGFR1::PLAG1, and a novel fusion, HMGA2::LINC02389. Most of the fusions were confirmed by FISH using PLAG1 (6/11) and HMGA2 (1/1) gene break probes. Split signals indicating gene break were identified by FISH for PLAG1 (12/17), HMGA2 (3/4), EWSR1 (7/22), and MYB (2/7). Concerning pathogenic mutations, only CXPA with epithelial differentiation (SDC) presented these alterations, including HRAS mutation (2/4), TP53 (1/4), PTEN (1/4), and ATK1 (1/4). In addition, amplifications in ERBB2 (17/35), MDM2 (1/4), and EWSR1 (1/7) were detected. A novel finding was the discovery of an HMGA2::LINC02389 fusion in 1 patient with EMC ex-PA. The present results indicate that molecular profiling of CXPA with myoepithelial differentiation (MC) tends to reveal chromosomal fusion events, whereas CXPA with epithelial differentiation (SDC) tends to have a higher frequency of pathogenic mutations and gene amplifications.

Vulvar lichen sclerosus (LS) is a common, chronic inflammatory disorder with a subset of cases progressing to differentiated vulvar intraepithelial neoplasia (dVIN) and/or squamous cell carcinoma (SCC). Histopathologic diagnosis of LS and dVIN can be challenging, and it is difficult to predict the subset of LS cases that progress. Immunohistochemistry (IHC) may be a useful diagnostic aid in this setting. CK17 has been shown to be overexpressed in invasive SCC and dVIN, and less commonly in LS. Similar to CK17, D2-40 has been correlated with cutaneous SCC prognosis but has not been evaluated in vulvar lesions. We identified a total of 13 patients with HPV-independent vulvar SCC that had precursor LS or dVIN. CK17 and D2-40 IHC stain intensity and pattern was scored in foci of LS, dVIN, and SCC. An increase in basal layer D2-40 expression was observed with progression from LS to dVIN with strong and diffuse staining in SCC. CK17 maintained similar stain intensity among squamous lesions, but displayed different patterns of staining, with superficial staining in LS, suprabasal staining in dVIN, and diffuse staining in SCC. A subset of LS cases displayed an intermediate (suprabasal) CK17 IHC profile, wild-type p53 expression, and cytomorphologic and architectural features intermediate between LS and dVIN; we defined such cases as "atypical LS." We found that a panel of D2-40/CK17 can serve as a diagnostic adjunct to differentiate LS, dVIN, and invasive SCC. Additional studies with larger patient cohorts are needed to validate these findings and determine their prognostic significance.