Micro-CT and high-field MRI for studying very early post-mortem human fetal anatomy at 8 weeks of gestation.

OBJECTIVE: This study involved very early post-mortem (PM) examination of human fetal anatomy at 8 weeks of gestation (WG) using whole-body multimodal micro-imaging: micro-CT and high-field MRI (HF-MRI). We discuss the potential place of this imaging in early first-trimester virtual autopsy. METHODS: We performed micro-CT after different contrast-bath protocols including diffusible iodine-based contrast-enhanced (dice) and HF-MRI with a 9.4 T machine with qualitative and quantitative evaluation and obtained histological sections. RESULTS: Nine fetuses were included: the crown-rump length was 10-24 mm and corresponded to 7 and 9 WG according to the Robinson formula. The Carnegie stages were 17-21. Dice micro-CT and HF-MRI presented high signal to noise ratio, >5, according to the Rose criterion, and for allowed anatomical phenotyping in these specimens. Imaging did not alter the histology, allowing immunostaining and pathological examination. CONCLUSION: PM non-destructive whole-body multimodal micro-imaging: dice micro-CT and HF-MRI allows for PM human fetal anatomy study as early as 8 WG. It paves the way to virtual autopsy in the very early first trimester. Obtaining a precision phenotype, even regarding miscarriage products, allows a reverse phenotyping to select variants of interest in genome-wide analysis, offering potential genetic counseling for bereaved parents.

One-step nucleic acid amplification for detecting lymph node metastasis of head and neck squamous cell carcinoma.

BACKGROUND: In head and neck squamous cell carcinoma (HNSCC) 30% of cN0 patients have occult metastasis. LN invasion is a major prognostic factor. Sentinel lymph node (SLN) is an option for cN0 neck management. One-step nucleic acid amplification (OSNA) used to analyze SLN in breast cancer is also a candidate to get more reliable intraoperative HNSCC lymph node (LN) staging. OBJECTIVE: To compare OSNA analysis to pathological analysis in cN0 HNSCC. MATERIALS AND METHODS: 157 LN from 26 cN0 HNSCC patients were prospectively analyzed (6.3LN/patient). Exclusion criteria were previous surgery or radiotherapy. Each node was cut into 4 equal pieces alternatively sent to pathological analysis and OSNA technique. IHC CK19 was performed on the primary tumor biopsy and RT-qPCR of CK19, PVA and EPCAM on the LN lysate of discordant cases. RESULTS: OSNA was able to provide intraoperative result in all patients. OSNA detected 21 metastases. There were 139 concordant LN (88.5%). There were 18 initial discordant LN (11.5%), 13 (8.3%) were OSNA positive/pathological analysis negative, 5 (3.2%) were OSNA negative/pathological analysis positive. After elimination of allocation bias, false negative rate was 1.3%, sensitivity and specificity were 90% and 95.6%, PPV and NPV were 75% and 98.5%. CONCLUSION: Our results suggest that OSNA should be considered to improve SNB analysis both for increasing micro metastasis diagnosis and offer extemporaneous results. Study registered under clinicaltrials.gov database number NCT02852343.

[Hepatic myelolipoma: A rare entity, case report and review of the literature]. / Myélolipome hépatique : une entité rare, à propos d'un cas et revue de la littérature.

Hepatic myelolipoma is a rare entity with only 17 cases described in the literature. A 73mm right liver mass was fortuitously discovered in a 55-year-old man. The biopsy showed normal hepatic tissue adjacent to a normal medular like hematopoïetic tissue, showing trilieage hematopoieses, including myeloid cells, erythroid cells and megakaryocytic cells. The diagnosis of hepatic myelolipoma was proposed. This benign tumor was initially described in adrenal gland, which is the most common topography. No malignancy or bleeding complication has been described in its hepatical location. The diagnosis is histological due to non-specific radiological presentation; it allows to avoid a surgical treatment in relation to its excellent prognosis. The etiology is not well established; but some hypotheses are discussed: adrenal or medullar heterotopia, bone marrow embolism, myeloïd metaplasia.

Diagnostic value of STMN1, LMO2, HGAL, AID expression and 1p36 chromosomal abnormalities in primary cutaneous B cell lymphomas.

AIMS: Distinction between primary cutaneous follicular lymphoma (PCFL) and primary cutaneous marginal zone lymphoma (PCMZL) is challenging, as clear-cut immunophenotypical and cytogenetic criteria to segregate both entities are lacking. METHODS AND RESULTS: To characterize PCFL and PCMZL more clearly and to define criteria helpful for the differential diagnosis, we compared expression of immunohistochemical markers [LIM-only transcription factor 2 (LMO2), human germinal centre-associated lymphoma (HGAL), stathmin 1 (STMN1), activation-induced cytidine deaminase (AID), myeloid cell nuclear differentiation antigen (MNDA)] and the presence of cytogenetic abnormalities described previously in nodal follicular lymphoma [B cell lymphoma 2 (BCL2) and BCL6 breaks, 1p36 chromosomal region deletion (del 1p36)] in a series of 48 cutaneous follicular and marginal zone lymphomas [cutaneous follicular lymphoma (CFL) and cutaneous marginal zone lymphoma (CMZL)]. Immunostaining for STMN1, LMO2, HGAL and AID allowed the distinction between CFL and CMZL, and STMN1 was the most sensitive marker (100% CFL, 0% CMZL). LMO2, HGAL and AID were positive in 93.2%, 82.1% and 86.2% CFL (all CMZL-negative). MNDA was expressed in both entities without significant difference (10.3% CFL, 30.8% CMZL, P = 0.18). BCL2, BCL6 breaks and the del 1p36 were present in 16.7%, 10.7% and 18.5% CFL and no CMZL. Finally, three and 29 CFL were reclassified as secondary cutaneous follicular lymphomas (SCFL) and PCFL without significant differences concerning phenotypical and cytogenetic features. BCL2, BCL6 breaks and the del 1p36 were present in 11.1%, 8% and 16.7% PCFL and did not impact the prognosis. CONCLUSION: LMO2, HGAL, STMN1 and AID, but not MNDA, are discriminant for the recognition between CFL and CMZL. BCL2, BCL6 rearrangements and the del 1p36 have a role in the pathogenesis of PCFL, the latest being the most common alteration.

Leukemic non-nodal mantle cell lymphomas have a distinct phenotype and are associated with deletion of PARP1 and 13q14.

Leukemic non-nodal mantle cell lymphoma (lMCL) is a particular subtype of mantle cell lymphoma (MCL), characterized by leukemic non-nodal disease and slow progression. Recognition of this entity is relevant to avoid overtreatment. Despite indolent clinical behaviour, lMCL might transform to a more aggressive disease. The purpose of this study was to compare lMCL with classical MCL (cMCL) and aggressive MCL (aMCL) using immunohistochemistry, interphase fluorescence in situ hybridization (FISH), and array-based comparative genomic hybridization, in order to identify biomarkers for lMCL diagnosis and prognosis. Seven lMCL patients were included. All had bone marrow involvement without lymphadenopathy. An lMCL phenotype was distinct from that of cMCL and aMCL: SOX11-, ATM+, PARP1+/-, and low KI67 (average 2 %). Beyond the t(11;14) translocation, fewer secondary cytogenetic alterations were found in lMCL compared to cMCL and aMCL, including deletion of PARP1 and 13q14. At last follow-up, one patient with lMCL had died of disease and another had progressive disease. These patients were respectively 13q14 deletion- and PARP1-positive. One other case of lMCL harbored a 13q14 deletion associated with PARP1 deletion. This patient had indolent disease. lMCL has a particular phenotype and fewer secondary cytogenetic alterations than cMCL and aMCL. PARP1 protein expression and 13q14 deletion are associated with a progressive clinical course of lMCL and should be included in initial diagnostic studies as predictors of unfavorable outcome. PARP1 deletion is involved in lMCL pathogenesis and might confer advantage.