We assessed the frequency of programmed death-ligand 1 (PD-L1) expression by immunohistochemistry (IHC) in a cohort of 522 sarcomas from 457 patients, incuding a subset of 46 patients with 63 matched ...samples from local recurrence or metastases with primary tumours and/or metachronous metastases. We also investigated the correlation of PD-L1 with the presence and degree of tumour-infiltrating lymphocytes (TILs) in a subset of cases. IHC was performed using the PD-L1 SP263 companion kit (VENTANA) on tissue microarrays from an archival cohort. Evaluation of PD-L1 and TILs was performed on full sections for a subset of 23 cases. Fisher's exact and Mann Whitney test were used to establish significance (P <0.05). PD-L1 positive expression (≥1%) was identified in 31% of undifferentiated pleomorphic sarcomas, 29% of angiosarcomas, 26% of rhabdomyosarcomas, 18% of myxofibrosarcomas, 11% of leiomyosarcomas and 10% of dedifferentiated liposarcomas. Negative expression was present in all atypical lipomatous tumous/well-differentiated lipoasarcomas, myxoid liposarcomas, synovial sarcomas, pleomorphic liposarcomas, and Ewing sarcomas. PD-L1 IHC was concordant in 81% (38 of 47) of matched/paired samples. PD-L1 IHC was discordant in 19% (9 of 47 matched/paired samples), displaying differences in the proportion of cells expressing PD-L1 amongst paired samples with the percentage of PD-L1-positive cells increasing in the metastatic/recurrent site compared to the primary in 6 of 9 cases (67%). Significant correlation between PD-L1 expression and the degree of TILs was exclusively identified in the general cohort of leiomyosarcomas, but not in other sarcoma subtypes or in metastatic/recurrent samples. We conclude that the prevalence of PD-L1 expression in selected sarcomas is variable and likely to be clone dependent. Importantly, we demonstrated that PD-L1 can objectively increase in a small proportion of metastases/recurrent sarcomas, offering the potential of treatment benefit to immune checkpoint inhibitors in this metastatic setting.
Fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) is a rare and recently described entity associated with hereditary leiomyomatosis and RCC syndrome. FH-deficient RCC may show ...variable clinical and pathologic findings, but commonly presents with locally advanced and metastatic disease and carries a poor prognosis. We identified 32 patients with FH-deficient RCC, confirmed by FH immunohistochemistry (IHC) and/or FH mutation analysis, and performed a retrospective review of the clinical and pathologic features. Median age at presentation was 43 years (range, 18 to 69 y), and the M:F ratio was 2.2:1. Median tumor size was 6.5 cm (range, 2.5 to 28 cm), and 71% presented at stage ≥pT3a. After a median follow-up of 16 months (range, 1 to 118 mo) in 26 patients, 19% showed no evidence of disease, 31% were alive with disease, and 50% were dead of disease. The vast majority of cases showed multiple histologic growth patterns, with papillary (52%) being the most common predominant pattern, followed by solid (21%), cribriform/sieve-like (14%), sarcomatoid (3%), tubular (3%), cystic (3%), and low-grade oncocytic (3%). Viral inclusion-like macronucleoli with perinucleolar clearing were present in almost all cases (96%). All cases were evaluated using FH IHC, and 3 cases (9%) showed retained FH expression. Nineteen cases had germline or tumor mutation analysis confirming a FH mutation, with 79% (11/14) of cases showing mutations within coding regions and 21% (3/14) showing mutations within intronic splice-sites. By IHC, 97% (32/33) of cases were negative for CK7, 93% (27/29) were negative for p63, and 52% (15/29) were negative for GATA3. All cases stained were positive for PAX8 and showed retained succinate dehydrogenase B expression. Our overall findings show that FH-deficient RCC is considerably heterogenous in morphology and frequently behaves aggressively. Suspicion for this entity should be raised even in the absence of predominantly papillary architecture and characteristic nucleolar features. We have included cases with uncommonly seen features, including 4 cases with predominantly cribriform/sieve-like architecture as well as one case with pure low-grade oncocytic morphology (9 y of clinical follow-up without evidence of disease). Although FH IHC is a useful tool for identifying cases of FH-deficient RCC, not all cases of FH-deficient RCC show loss of FH staining, and FH mutation analysis should be considered for patients with suspicious clinical or pathologic features, even in cases with retained FH IHC expression.
ObjectivesIn the face of unprecedented demand, the Welsh Ambulance Services University NHS Trust developed ‘Blue Light Hub’: a new app to educate primary school-aged children about emergency ...services. Our overarching aim was to examine the effectiveness of the app.DesignPrimary school-aged children from three schools in South Wales, UK, played with the app for 2 hours over 2 weeks in class time. Children completed quizzes to assess their knowledge and awareness of, and confidence in engaging with, emergency services before and after using the app.ParticipantsOur evaluation focused on N=393 children who completed both the pre-test and post-test quizzes. On average, children were 8–9 years old (median school year, Year 4); 47.8% were male and 50.9% were female.ResultsAfter using the app, there was a significant increase in the proportion of children who knew of appropriate actions to take in non-emergency scenarios, χ2(1) = 26.01, and could provide a question a call handler would ask them if they called 999, χ2(1) = 13.79. There was also an increase in the proportion of children who could identify an National Health Service (NHS) service that could help them if they were unwell, χ2(1) = 33.31, name different roles in the NHS, χ2(1) = 12.80 and knew how dialling 111 could help them χ2(1) = 90.05 (all p values<0.001).ConclusionTo our knowledge, Blue Light Hub is the first app of its kind designed to educate primary school-aged children about emergency services. Our findings provide preliminary evidence that the app supports children’s knowledge and awareness of emergency services.
Background
T‐cell‐rich angiomatoid polypoid pseudolymphoma (TRAPP) and inflammatory lobular hemangioma (ILH) encompass a spectrum of cutaneous vascular lesions in which a prominent lymphoplasmacytic ...component may impart a pattern highly reminiscent of low‐grade cutaneous lymphoma (pseudolymphoma). Epithelioid hemangioma, including its most common variant angiolymphoid hyperplasia with eosinophilia (ALHE), is a distinct entity associated with FOS and/or FOSB expression detected by immunohistochemistry (IHC). These entities can show significant morphological overlap.
Methods
We performed IHC for FOSB, FOS, and lymphoid markers in a series of TRAPP/ILH and ALHE.
Results
We identified 13 cases of ILH/TRAPP, which showed a predominance in CD8+ T‐cells (CD8>CD4: 11/13) while FOSB and FOS were expressed in 36% (4/11) and 27% (3/11) of cases, respectively. ALHE (n = 9) showed a predominance in CD4+ T‐cell (67%) with FOSB and FOS co‐expression in 78% (seven of nine) of the cases.
Conclusion
We showed, based on FOS and/or FOSB immunohistochemical expression, that there is a possible link between ILH/TRAPP and epithelioid hemangioma/ALHE. The use of FOS and FOSB IHC in the routine diagnostic setting of cutaneous vascular lesions will help to redefine cases of ILH/TRAPP as a subset of these may represent inflammatory variants of epithelioid hemangioma.
Aims
Synovial sarcoma is defined by recurrent t(X;18)(p11;q11) translocations creating SS18–SSX1, SS18–SSX2 or SS18–SSX4 fusions. Recently, a novel rabbit monoclonal antibody designed to identify ...these fusions (SS18–SSX, clone E9X9V) was proposed to be highly specific (100%), but not completely sensitive (95%) for this diagnosis. Another antibody designed to identify the C‐terminal end of SSX (SSX_CT, clone E5A2C) was proposed to be highly sensitive (100%), but not completely specific (96%). We sought to validate these antibodies in an independent cohort.
Methods and results
We performed immunohistochemistry for SS18–SSX and SSX_CT on 39 synovial sarcoma samples from 25 patients with confirmed gene rearrangements. Thirty‐four (87%) and 36 (92%) were positive for SS18–SSX and SSX_CT, respectively. False‐negative staining was associated with suboptimally handled small biopsies and decalcified specimens, even when staining was diffuse and strong in subsequent optimally processed excisions and non‐decalcified areas. None of 580 non‐synovial sarcoma tumours (76 whole sections, 504 TMA samples) were positive for SS18–SSX (100% specificity), whereas 39 (93% specificity) were positive for SSX_CT.
Conclusions
SS18–SSX fusion‐specific IHC is 87–95% sensitive for the diagnosis of synovial sarcoma and highly (perhaps perfectly) specific. Therefore, positive SS18–SSX staining definitively confirms the diagnosis of synovial sarcoma. SSX_CT is less specific (93–96%) but highly sensitive (92%, but approaching 100% when suboptimally processed biopsies and decalcified specimens are excluded). Negative SSX_CT staining may therefore have an ancillary role as a rule‐out test for synovial sarcoma. We caution that both antibodies are prone to false‐negative staining in decalcified specimens.
Angiomatoid fibrous histiocytoma (AFH) is a soft tissue tumour of intermediate (rarely metastasising) malignant potential, which harbours
gene fusions. These tumours can express anaplastic lymphoma ...kinase (ALK) in the absence of gene rearrangement or copy number alteration and can also coexpresses Pan-TRK immunohistochemistry (IHC). All
-rearranged AFH were retrieved from the files of three institutions and Pan-TRK (EPR17341), ALK and BRAF V600E IHC were performed. Fourteen AFH cases were identified, which included three cases of intracranial mesenchymal tumours with FET-CREB fusions. PanTRK and ALK positive immunostaining was identified in 9 (64.2%) and 12 (85.7%) cases, respectively. No
or
translocations or increased copy number/amplification were identified in all eight cases which had fluorescence in situ hybridisation and/or next generation sequencing for
and
available for assessment. None of the cases expressed BRAF-V600E.Although our study is limited, our report is the first to document PanTRK expression in AFH in the absence of identifiable
gene alterations.
Aims
Spermatocytic tumour (ST) is a rare testicular germ cell neoplasm with few confirmatory biomarkers that can be challenging to diagnose. Like normal spermatogonia, STs are known to express SSX ...proteins. Recently, a novel SSX antibody directed against a conserved C‐terminal region of SSX1, SSX2 and SSX4 (SSX_CT) has emerged as a reliable biomarker for these SSX proteins and synovial sarcoma. However, SSX_CT immunostaining has not been demonstrated in ST. The aim of this study was to assess the diagnostic utility of SSX_CT immunohistochemistry in ST and other tumours in the differential diagnosis with ST.
Methods and results
SSX_CT, OCT3/4 and c‐KIT immunohistochemistry was performed on 15 STs, 38 seminomas, 13 embryonal carcinomas, 12 yolk sac tumours, six choriocarcinomas, four teratomas, seven Sertoli cell tumours, and six lymphomas. Staining was scored as negative, rare, focal, or diffuse. SSX_CT was positive in all (15/15) STs, and diffusely positive in 14 of 15 (93%). SSX_CT was positive in 22 of 38 (58%) seminomas; however, only two cases showed diffuse expression. SSX_CT was negative in all other tumours. OCT3/4 was negative in all STs, but positive in all seminomas and embryonal carcinomas. c‐KIT was frequently positive in both STs (12/15; 80%) and seminomas (33/38; 87%). OCT3/4 and c‐KIT were negative in all other tumours.
Conclusions
SSX_CT is a valuable and highly sensitive biomarker that supports the diagnosis of ST. Diffuse expression of SSX‐CT in STs is also highly specific for ST. Nevertheless, SSX_CT is best used in combination with OCT3/4 when ST is in the differential diagnosis.
In this study we used the Illumina Infinium Methylation array to investigate in a cohort of matched archival human tissue samples (n = 32) from 14 individuals with soft tissue sarcomas if genome-wide ...methylation changes occur during metastatic and recurrent (Met/Rec) disease. A range of sarcoma types were selected for this study: leiomyosarcoma (LMS), myxofibrosarcoma (MFS), rhabdomyosarcoma (RMS) and synovial sarcoma (SS). We identified differential methylation in all Met/Rec matched samples, demonstrating that epigenomic differences develop during the clonal evolution of sarcomas. Differentially methylated regions and genes were detected, not been previously implicated in sarcoma progression, including at PTPRN2 and DAXX in LMS, WT1-AS and TNXB in SS, VENTX and NTRK3 in pleomorphic RMS and MEST and the C14MC / miR-379/miR-656 in MFS. Our overall findings indicate the presence of objective epigenetic differences across primary and Met/Rec human tissue samples not previously reported.
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