Increase of follicular helper T cells skewed toward a Th1 profile in CVID patients with non-infectious clinical complications.

Common variable immunodeficiency (CVID) is characterized by low levels of circulating immunoglobulins and defects in B cell maturation leading to an increased susceptibility to infections. Some patients develop complications such as autoimmune diseases, enteropathy, and lymphoproliferation, resulting in higher morbidity and mortality. Follicular helper T (Tfh) cells are specialized in helping B cell differentiation into Ig-producing cells. Three subsets have been described, namely non B-cell helper Tfh1 and the two B-helper cell subsets Tfh2 and Tfh17. We determined that circulating Tfh cells were elevated in CVID patients and skewed toward a Tfh1 profile. Interestingly, elevated levels of Tfh1 cells were significant only in patients harboring non-infectious complications regardless of the type of complication and inversely correlated with switched memory B cells. Moreover, CXCR3+ cells are increased in splenic CVID germinal centers. Our observations suggest that the altered balance in Tfh subsets in CVID is linked to a more severe disease.

Detection of the Merkel cell polyomavirus in the neuroendocrine component of combined Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. The main etiological agent is Merkel cell polyomavirus (MCPyV), detected in 80% of cases. About 5% of cases, called combined MCC, feature an admixture of neuroendocrine and non-neuroendocrine tumor cells. Reports of the presence or absence of MCPyV in combined MCC are conflicting, most favoring the absence, which suggests that combined MCC might have independent etiological factors and pathogenesis. These discrepancies might occur with the use of different virus identification assays, with different sensitivities. In this study, we aimed to determine the viral status of combined MCC by a multimodal approach. We histologically reviewed 128 cases of MCC and sub-classified them as "combined" or "conventional." Both groups were compared by clinical data (age, sex, site, American Joint Committee on Cancer [AJCC] stage, immunosuppression, risk of recurrence, and death during follow-up) and immunochemical features (cytokeratin 20 and 7, thyroid transcription factor 1 [TTF1], p53, large T antigen [CM2B4], CD8 infiltrates). After a first calibration step with 12 conventional MCCs and 12 cutaneous squamous cell carcinomas as controls, all eight cases of combined MCC were investigated for MCPyV viral status by combining two independent molecular procedures. Furthermore, on multiplex genotyping assay, the samples were examined for the presence of other polyoma- and papillomaviruses. Combined MCC differed from conventional MCC in earlier AJCC stage, increased risk of recurrence and death, decreased CD8 infiltrates, more frequent TTF1 positivity (5/8), abnormal p53 expression (8/8), and frequent lack of large T antigen expression (7/8). With the molecular procedure, half of the combined MCC cases were positive for MCPyV in the neuroendocrine component. Beta papillomaviruses were detected in 5/8 combined MCC cases and 9/12 conventional MCC cases. In conclusion, the detection of MCPyV DNA in half of the combined MCC cases suggests similar routes of carcinogenesis for combined and conventional MCC.

Adult Primary Immune Thrombocytopenia: Spleen Histology Findings and Outcomes According to Rituximab Use Based on Analysis of 41 Cases.

Immune thrombocytopenia (ITP) is an acquired antibody-mediated disease, for which splenectomy remains a curative treatment. We analyzed histology and phenotypes of ITP-splenectomy specimens from 41 adult patients, with different previous ITP-specific treatments, including B-cell-depleting rituximab (RTX) or not, in an attempt to predict splenectomy success or failure on the basis of day 56 postoperative platelet counts. RTX-naive ITP-spleen samples, compared with those from a 20-patient control trauma cohort, contained the following nonspecific, ITP-evocative, white-pulp lesions: follicular helper T-cell (programmed death-1 and inducible T-cell COStimulator) expansion in reactive follicles (P=0.01 and 0.03, respectively) and regulatory T-cell (FOXP3) expansion in the T-cell zone (P=0.049). On comparing ITP-splenectomy samples that would be successful with those that would be failures, only marginal zone hyperplasia differed (P=0.017). Indeed, 13/21 (61.9%) successful splenectomy samples exhibited marginal zone hyperplasia, as opposed to 1/9 (11.1%) failed splenectomy specimens. RTX impact on ITP-splenectomy samples was characterized by white-pulp (P=0.03) and marginal zone atrophies (P=0.01), and periarteriolar T-cell-zone hyperplasia (P<0.0001). The results of this novel comparative study of the histologic patterns of 41 ITP patients' evocative splenic lesions enabled clear description of different ITP morphologies and phenotypes, as a function of prior treatment and splenectomy success or failure.

Urothelial carcinoma in first histological diagnosis of patients over 80 years has distinctive histological features: a retrospective single-institution study of 185 patients.

Few histological data are known about patients with a first diagnosis of bladder cancer (BC) at the age ≥80 years. We describe the largest series in this patient group and their distinctive histological features. This unicentric retrospective study included patients at the age ≥80 years with a first diagnosis of bladder cancer between 2005 and 2015. All diagnosis was made by one senior uropathologist according to the WHO 2016 classification, pTNM 7th edition 2009. We examined samples of 185 patients, sex ratio M:W = 2.49:1, with ≥80 years at the time of first diagnosis of BC. The mean age was 85.1 years (84.8 for men and 85.8 for women). One hundred sixteen patients were diagnosed with NMIBC (non-muscle invasive bladder cancer) (62.7%). Sixty-nine patients were detected with MIBC (muscle invasive bladder cancer) (37.3%). In the MIBC, 20 (29.0%) cases, a divergent differentiation was reported. No patient had primary carcinoma in situ (Cis) at time of diagnosis, and concomitant Cis was observed in 18.9% (35 cases). According to our results, the histopathological findings are different from those of other patients' groups. The study shows a higher number of MIBC and a high percentage of histological variants. We could show distinctive pathological features in this patient group.

[From new genetic and histological classifications to direct treatment]. / Carcinome urothélial : des classifications histologiques et moléculaires vers un traitement adéquat.

The most important criterion for optimal cancer treatment is a correct classification of the tumour. During the last three years, several very important progresses have been made with a better definition of urothelial carcinoma (UC), especially from a molecular point of view. We start having a global understanding of UC, although many details are still not completely understood.

Spleen Histologic Appearance in Common Variable Immunodeficiency: Analysis of 17 Cases.

Histologic and phenotypic analyses of splenectomy samples from 17 patients with common variable immunodeficiency (CVID) showed the following nonspecific, evocative, white-pulp lesions: white-pulp hyperplasia (WPH) with reactive follicles, giant follicles (GFs), marginal zone hyperplasia, periarteriolar T-zone hyperplasia (PATH) and/or granulomas, which enabled us to discern 2 groups: the first (n=6) composed of WPH with reactive follicles without granulomas, and the second (n=9) characterized by the presence of granulomas with or without WPH. All specimens were Epstein-Barr virus negative by in situ hybridization. Molecular analyses revealed a polyclonal immunoglobulin heavy chain gene (IGH) rearrangement (n=12). WPH-only patients were mostly female individuals and younger at CVID onset, diagnosis, and splenectomy, but their interval between the first symptom and diagnosis was longer; they had more associated infectious events, autoimmune disease, pulmonary complications, and liver regenerative nodular hyperplasia; their IgG, IgA, and IgM concentrations were also higher. Granuloma-group patients were mostly male individuals; were older at CVID onset, diagnosis, and splenectomy; had disseminated granulomatous disease, but infectious events, autoimmune disease, pulmonary complications, and liver regenerative nodular hyperplasia were less common; their immunoglobulin concentrations were lower. Histologic comparisons between the WPH-only and granuloma groups showed more intense WPH and more intense marginal zone hyperplasia and fewer GFs in the former versus more developed PATH and more common GFs in the latter. The results of this novel comparative study of the histologic patterns of 17 CVID patients' evocative splenic lesions suggested different biological and clinical profiles.

HOXB13 protein expression in metastatic lesions is a promising marker for prostate origin.

The HOXB13 gene is a member of the homeobox gene family, and prostate development depends on HOXB13 function. HOXB13 is a very sensitive and specific marker of prostate tissue and prostate cancer. When the origin of a tumor in a resection specimen or in biopsy material is unclear, it allows determining the prostate as the primary. Our aim was to determine whether HOXB13 has similar sensitivity for determining prostate origin of lymph node and bone metastases. We retrieved cases of lymph node and bone metastases of histologically confirmed prostate cancer (PCa) and selected lymph node metastases of urothelial carcinoma (UCa). A panel of antibodies against HOXB13, PSA, ERG, Androgen receptors, p504S, p63, GATA-3, CK7, and Uroplakin 2 and 3 was tested on these tissue samples. Two pathologists analysed and scored staining as either 0 (negative) or + (positive). The selected cohort consisted of 74 cases of lymph node and 15 of bone metastases of PCa and 15 of lymph node metastases of UCa. HOXB13 was expressed in 93 % of lymph node and in 33 % of bone metastases of PCa. All lymph node metastases of UCa were negative. Sensitivity of HOXB13 as a marker for prostate origin in lymph node metastases was 93 % and for bone metastases 33 %. Inter-observer variability in assessment of staining was good, as only two (1.9 %) of lymph node metastasis of PCa were discordant. HOXB13 is a useful marker for prostate origin when doubt exists regarding the site of the primary of a metastatic lesion. On bone metastases, HOXB13 immunohistochemistry performed less well, probably due to the use of tissue decalcification.

Primary digestive melanoma in association with tubular adenoma: a case report illustrating the distinction from metastatic colonic melanoma.

We report here an exceptional pattern of atypical lentiginous melanocytic proliferation within an adenoma, leading to focal lamina propria infiltration and pulmonary metastasis, which was considered as primary colonic mucosal melanoma (MM) in a Caucasian patient. Such case illustrates the diagnosis criteria required to differentiate primary MM from colonic metastasis of melanoma, including the absence of past history of other primary melanoma, a unique colonic and abdominal lesion with predominant features of in situ lentiginous MM and a very focal and unique invasive area without other digestive tract or abdominal localization. This tumor displayed a KIT exon 11 mutation leading to a unique combination of p.I571M and p.D572G deleterious amino acid changes. Such pattern also favors the diagnosis as KIT appears as a master oncogenic player in MM oncogenesis.