ABSTRACT
Objective@#To understand the consistency of ALK Ventana-D5F3 immunohistochemistry (IHC) interpretation in Chinese lung adenocarcinoma among histopathologists from different hospitals, and to recommend solution for the problems found during the interpretation of ALK IHC in real world, with the aim of the precise selection of patients who can benefit from ALK targeted therapy.@*Methods@#This was a multicenter and retrospective study. A total of 109 lung adenocarcinoma cases with ALK Ventana-D5F3 IHC staining were collected from 31 lung cancer centers in RATICAL research group from January to June in 2018. All cases were scanned into digital imaging with Ventana iSCANcoreo Digital Slide Scanning System and scored by 31 histopathologists from different centers according to ALK binary (positive or negative) interpretation based on its manufacturer′s protocol. The cases with high inconsistency rate were further analyzed using FISH/RT-PCR/NGS.@*Results@#There were 49 ALK positive cases and 60 ALK negative cases, confirmed by re-evaluation by the specialist panel. Two cases (No. 2302 and No.2701) scored as positive by local hospitals were rescored as negative, and were confirmed to be negative by RT-PCR/FISH/NGS. The false interpretation rate of these two cases was 58.1% (18/31) and 48.4% (15/31), respectively. Six out of 31 (19.4%) pathologists got 100% accuracy. The minimum consistency between every two pathologists was 75.8%.At least one pathologist gave negative judgement (false negative) or positive judgement (false positive) in the 49 positive or 60 negative cases, accounted for 26.5% (13/49), 41.7% (25/60), respectively, with at least one uncertainty interpretation accounted for 31.2% (34/109).@*Conclusion@#There are certain heterogeneities and misclassifications in the real world interpretation of ALK-D5F3 IHC test, which need to be guided by the oncoming expert consensus based on the real world data.
ABSTRACT
Objective@#To investigate the multidirectional differentiation potential in epithelioid sarcoma (ES), with special emphasis on its mesothelial and lymphatic endothelial markers expression.@*Methods@#Ten cases of distal-type ES were included. The clinical, histological, and immunohistochemical(including mesothelial and lymphatic endothelial markers expression)features and follow-up data were evaluated.@*Results@#The patients aged between 8 to 66 years. Five cases were male and five were female. The tumors were located at the palm (2 cases), wrist (3 cases), upper arm (2 cases), poplitealfossa (1 case), lower leg (1 case) and thigh (1 case), respectively. Clinically, most cases presented as painful, firm subcutaneous nodules. Histologically, the tumors were mainly composed of epithelioid, rhabdoid, spindle, or transitional cells, with abundant eosinophilic cytoplasm, oval and vesicular nucleus, and one or more prominent nucleoli. They were arranged in nodular, diffuse nodular or sheet like growth patterns, frequently with necrosis at the center with vague granulomatous configuration. Immunohistochemically, all tumors expressed cytokeratins, epithelial membrane antigen, CD34, desmin, mesothelial markers such as Calretinin, WT1, D2-40, M2A, vascular and lymphatic endothelial markers FLI-1, and VEGFR-3. The tumor cells did not express CD31, FⅧRAg, HHF35, HMB45, Melan A, MyoD1, myogenin, S-100 protein and SMA. All 10 patients underwent radical resection or extended excision, with additional radiotherapy or chemotherapy. During the follow-up from October 2012 to August 2016, seven cases showed recurrences and metastases within 2 months to 2 years. Five patients died of the disease due to widespread metastases.@*Conclusions@#ES may show a wide spectrum of morphology, and display a multidirectional differentiating capabilities including towards mesothelial and lymphatic endothelial cells. As such, its diagnosis and differential diagnosis are particularly important as it is easily confused with other tumors with similar morphology or immune phenotype.
ABSTRACT
Objective@#To analyze the clinical and pathological features of Kaposiform hemangioendothelioma (KHE), and to investigate the role of master transcriptional factor Prox-1 in the regulation of lymphatic differentiation.@*Methods@#Nine cases of KHE (during the period from October 2009 to June 2016) were collected with clinical and pathological data. H&E stained section review and immunohistochemietry using the Dako EnVision method were performed.@*Results@#There were 6 female and 3 male patients with age ranging from 2 months to 8 years (median 3 years and 4 months). The patients presented with either single subcutaneous soft tissue mass, or bone tumors, with the duration of disease onset ranging from 1 month to 1 year. The sites of involvement included the skins of neck (2 cases), nose root (1 case), inguinal (1 case), thigh root (1 case), humerus (2 cases), lumbar vertebrae(1 case), and mesentery (1 case). These tumors were histologically composed of nodules of densely packed spindle or ovoid cells and deformed small blood vessels in an invasive growth pattern. The tumor cells were immunohistochemically positive for both blood vessels and lymphatic endothelial markers, including Prox-1, the master transcriptional factor, and VEGFR-3. With followed-up from 1 to 60 months (median 26 months), two patients died of the disease, while the remaining patients were alive without recurrence.@*Conclusions@#KHE is a rare vascular tumor with at least partial lymphatic endothelial differentiation, in which Prox-1 may act as a master regulator for such differentiation. KHE is an aggressive tumor of intermediate malignant potential, with local invasion and recurrence tendency, and long term follow-up is required.