Useful histopathologic features for diagnosing focal liver lesions with spindle cell morphology: A clinicopathologic study

BackgroundFocal liver lesions with spindle cell morphology are rare in the daily practice of pathology. The differential diagnosis is broad, including both tumors and tumor-like lesions. Initial radiologic assessment is sometimes inaccurate. Histopathology is needed to arrive at the correct diagnosis. This study analyzed discrepancies between histopathology and radiologic findings of focal liver lesions with spindle cell morphology.MethodsA six-year retrospective analysis was conducted at a tertiary hospital in Thailand. All focal liver lesions with spindle cell morphology were retrieved. Clinicopathologic features of these cases were analyzed. The pathological diagnosis was rendered primarily based on routine histopathology, using other ancillary studies as an adjunct.Results287 biopsies and 151 resection specimens with focal liver lesions were identified. In 12 (2.7%) cases, tumors or tumor-like lesions with spindle cell morphology were retrieved. A total of five cases had discrepancies between histopathology and radiologic findings. These lesions encompassed primary liver tumors (EBV-associated smooth muscle tumor and leiomyosarcoma); metastatic tumors (gastrointestinal stromal tumor, small cell neuroendocrine carcinoma); and a tumor-like lesion (endometriosis). Several morphologic findings (i.e., cytologic grades, dense and loose areas, intratumoral lymphocytes, distinct perinuclear vacuoles, and hemosiderin) are important clues to diagnose these spindle cell lesions.ConclusionsPathologists play a critical role in diagnosing focal liver lesions with spindle cell morphology, particularly those with limited clinical data at the initial presentation. A thorough evaluation of histomorphology on routine hematoxylin and eosin-stained slides is essential for correct diagnosis.     

Challenges and limitation of MTAP immunohistochemistry in diagnosing desmoplastic mesothelioma/sarcomatoid pleural mesothelioma with desmoplastic features

AimGenomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear.Methods and resultsWe evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity.ConclusionsMTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available.     

Management of calcium pyrophosphate crystal deposition disease: A systematic review

ObjectiveCalcium pyrophosphate crystal deposition disease (CPPD) is a common cause of acute and chronic arthritis, especially in the elderly population. There is a paucity of data regarding the management of CPPD disease, which is currently based on expert opinion and evidence derived from the treatment of gout. We conducted a systematic literature review in order to identify the available treatment options for CPPD, and describe their efficacy and safety.Material and methodsOnline databases were searched from inception to May of 2020 using the search terms: (CPPD [Title/Abstract] OR CPDD [Title/Abstract] OR calcium pyrophosphate [Title/Abstract] OR chondrocalcinosis [Title/Abstract]) AND (treatment [Title/Abstract] OR management [Title/Abstract] OR therapy [Title/Abstract]). Articles evaluating the use of specific treatment agents for CPPD were eligible for inclusion. Case reports were excluded.ResultsA total of 22 eligible studies and 403 unique patients were selected. We identified only 3 randomized, double-blind, controlled trials (RCTs) evaluating the use of methotrexate, hydroxychloroquine, and magnesium carbonate in CPPD, and these therapeutic options, with the exception of methotrexate, have shown efficacy and reduction of pain intensity. Further, 10 case series and 9 cohort studies were included. Intramuscular and intra-articular glucocorticoids, ACTH, as well as the biologic agents anakinra and tocilizumab appear to be efficacious in CPPD. Intra-articular injections of glycosaminoglycan polysulphate, hyaluronic acid and yttrium, as well as synovial membrane destruction by laser irradiation were associated with symptomatic improvement. Due to significant study heterogenicity, direct comparison between studies was not possible.ConclusionThere are a limited number of studies evaluating the treatment of CPPD. High quality evidence is rather limited, while commonly administered agents such as NSAIDs, colchicine and corticosteroids have not been evaluated by RCTs. The need for high quality evidence supporting specific treatment modalities is urgent for this common yet neglected form of arthritis.