Human pathology最新文献

Mullerian adenosarcoma is a rare malignant biphasic tumor. The mesenchymal component may be low or high grade, with or without sarcomatous overgrowth (SO). Little is known about the molecular heterogeneity of these tumors. In this study, we aim to reclassify a large retrospective monocentric cohort of uterine adenosarcomas according to tumor grade and SO, to evaluate the clinical significance of pathological classification and to correlate with copy-number variations inferred from single nucleotide polymorphism array. Of the 67 uterine adenosarcomas, 18 (26.9%) were low grade without SO, 7 (10.4%) low grade with SO, 8 (11.9%) high grade without SO and 34 (50.7%) high grade with SO. SO, necrosis and RMS were more frequent in high grade than low grade adenosarcomas (p < 0.001). Low-rank test showed that recurrence-free survival was significantly shortened in high grade than low grade adenosarcomas (p = 0.035) and SO was associated with shortened overall and recurrence-free survival (p = 0.038 and p = 0.009, respectively). High-grade tumors displayed complex genomic profiles with multiple segmental losses including TP53, ATM and PTEN genes. The median genomic index was significantly higher in high grade than low grade tumors (27 [3–60] vs 5,3 [0–16], p < 0.0001) and was significantly higher in presence of SO in low grade tumors (12,8 [10–16] vs 2,6 [0–10], p = 0.0006). We propose to report sarcomatous overgrowth with the tumor grade for prognostication in adenosarcoma and representative sampling is crucial for evaluation of these histological criteria.

Plasmacytoid urothelial carcinoma (UC) is a rare histologic subtype of bladder cancer that is associated with an aggressive clinical behavior. We analyzed the clinicopathologic and molecular features of plasmacytoid UC in 52 patients from a single institute. The patients included 44 men and 8 women, with a mean age of 64 years (range, 41–91 years). All bladder cancers were high-grade UC, and plasmacytoid component accounted for a mean of 47% of bladder tumors (range, 5–100%). Distinct gene mutations were found in most plasmacytoid UCs (n = 49); the most common mutations were TP53 (n = 30), followed by TERT (n = 20), and CDH1 (n = 18). Copy number analysis was performed in 34 patients, and 13 of them showed copy number variations. Expression of HER2 was analyzed in 18 patients by immunohistochemistry, and 3 of them showed HER2 overexpression, which was confirmed by fluorescence in situ hybridization analysis. Thirty-two patients died of disease in a median of 15 months (range, 1–45 months). No individual gene mutations were significantly associated with clinical outcome, but mutations in the mammalian target of rapamycin (mTOR) pathway, including PICK3CA and PIK3R1 mutations, were associated with a significantly shorter survival duration (p < 0.05). Plasmacytoid UC is an aggressive histologic subtype that demonstrates frequent somatic gene mutations and CNVs, which may underlie its oncogenesis and progression. Gene mutations of the mTOR pathway are associated with poor outcome in a subset of patients with plasmacytoid UC.

Aims

Appendiceal mucinous neoplasms feature neoplastic mucinous epithelium with pushing borders and densely fibrotic walls. We have identified five examples of analogous colorectal tumours.

Methods and results

Slides, pathology reports, and clinical data were reviewed. Whole genome sequencing was performed in two cases. Three were women and the mean age was 70. Associated GI conditions included Crohn's disease [1], diverticulosis [2], and sarcoma of the terminal ileum [1]. Signs/symptoms included obstruction [2], nausea, vomiting, abdominal pain [1], and positive faecal immunohistochemical test [1]. Colonoscopic findings included narrowing [1], “fullness” [1], and caecal lesion concerning for GIST [1]. Tumours involved the rectosigmoid [2], sigmoid [1], transverse colon [1], and cecum [1] and ranged from 1.5 cm to 8.5 cm. All but one tumour arose in the setting of faecal stream abnormalities related to obstruction, diverticulosis, or bowel diversion. All cases showed columnar, variably mucinous epithelium associated with little-to-no lamina propria. All but one case showed fibrosis of the submucosa. Three cases had high-grade areas. Neoplastic glands and/or mucin dissected through the muscularis propria or subserosa in 3 examples. No extracolonic neoplastic cells/mucin, infiltrative invasion, or desmoplastic response were identified. Three patients with available follow-up [5.5–28 months] are alive. Whole genome sequencing identified pathogenic TP53 and ERBB2 variants, as well as ERBB2 copy number amplification in one high-grade example.

Conclusions

Though these tumours share clinicopathologic characteristics with their appendiceal counterparts, our cohort is too small to draw solid conclusions. We propose the term “extra-appendiceal mucinous neoplasm [EAMN]” for these rare lesions.

Collagenous spherulosis (CS) is a rare breast lesion of unknown histogenesis. Adenoid cystic carcinoma (ACC) is a rare basal-like breast carcinoma with low histological grade. CS is a benign lesion but resembles ACC. Both lesions show a similar histomorphology and feature bilineage differentiation. This study compared immunohistochemical markers in CS and ACC.

We compiled n = 13 CS cases and n = 18 mammary ACCs. Fourteen marker proteins (ER, PR, HER2, GATA3, CK7, E-cadherin, CD117, CK5/14, p40, p63, SMA, CD10, calponin, P-cadherin) were evaluated by immunohistochemistry (IHC). MYB rearrangement, a common alteration in ACC, was assessed by fluorescence in situ hybridization.

Patient age ranged between 40-60 years for CS lesions and 30–90 years for ACCs. 7/13 (54%) CS cases harbored a lobular carcinoma in situ (LCIS) in the luminal component. One CS/LCIS lesion occurred in a carrier of a pathogenic germline variant in CDH1/E-cadherin. MYB rearrangement was detected in 0/11 (0%) CS and 6/16 (37%) ACC cases (P = 0.054). CS was associated with expression of ER in the luminal component (P < 0.001), E-cadherin loss in the luminal component (P = 0.045), and expression of CD10 and calponin in the basal component (P < 0.001). Furthermore, CS was associated with GATA3 expression in the luminal component (12/13 [92%] versus 5/18 [27%], P < 0.001).

In summary, IHC for GATA3 and E-cadherin may contribute to the differential diagnosis between CS and ACC, although these markers are not exclusively expressed in either lesion. Histologic evaluation has to take into account that CS is frequently colonized by LCIS, requiring thorough correlation of histomorphology and immunohistochemical features.

This study investigated the clinicopathological, immunohistochemical, and molecular features of primary leptomeningeal melanocytic neoplasms (LMNs). Twelve LMN cases were retrospectively reviewed. We performed Fluorescence in-situ hybridization (including a 4-probe FISH assay with CDKN2A and MYC assay) and Next-Generation sequencing analyses on available cases. Histologically, 2 tumours were classified as melanocytomas (MC), 2 as intermediate-grade melanocytomas (IMC), and 8 as leptomeningeal melanomas (LMM). Two rare cases of LMM were associated with large plaque-like blue nevus. One MC case was associated with Ota. Ten cases (83.3%) showed melanocytic cells with benign features diffusely proliferating within the meninges. The Ki-67 in three categories differed (MC 0–1%, IMC 0–3%, LMM 3–10%). 57.1% of LMM cases (4/7) were positive for FISH. Nine of 10 tumours harboured activating hotspot mutations in GNAQ, GNA11, or PLCB4. Additional mutations of EIF1AX, SF3B1, or BAP1 were found in 40%, 30%, and 10% of tumours, respectively. During the follow-up (median = 43 months), 5 LMM patients experienced recurrence and/or metastasis, 3 of them died of the disease and the other 2 are alive with the tumour. Our study is by far the first cohort of LMN cases tested by FISH. In addition to morphological indicators including necrosis and mitotic figures, using a combination of Ki-67 and FISH helps to differentiate between IMC and LMM, especially in LMM cases with less pleomorphic features. SF3B1 mutation is first described in 2 cases of plaque-type blue nevus associated with LMM. Patients with SF3B1 mutation might be related to poor prognosis in LMN.

Introduction

Semi-quantitative scoring of various parameters in renal biopsy is accepted as an important tool to assess disease activity and prognostication. There are concerns on the impact of interobserver variability in its prognostic utility, generating a need for computerized quantification.

Methods

We studied 94 patients with renal biopsies, 45 with native diseases and 49 transplant patients with index biopsies for Polyomavirus nephropathy. Chronicity scores were evaluated using two methods. A standard definition diagram was agreed after international consultation and four renal pathologists scored each parameter in a double-blinded manner. Interstitial fibrosis (IF) score was assessed with five different computerized and AI-based algorithms on trichrome and PAS stains.

Results

There was strong prognostic correlation with renal function and graft outcome at a median follow-up ranging from 24 to 42 months respectively, independent of moderate concordance for pathologists scores. IF scores with two of the computerized algorithms showed significant correlation with estimated glomerular filtration rate (eGFR) at biopsy but not at the end of follow-up. There was poor concordance for AI based platforms.

Conclusion

Chronicity scores are robust prognostic tools despite interobserver reproducibility. AI-algorithms have absolute precision but are limited by significant variation when different hardware and software algorithms are used for quantification.

Mucinous tubular and spindle cell carcinoma (MTSCC) shows significant overlap with papillary renal cell carcinoma (PRCC), and harbor recurrent copy-number alterations (CNA).

We evaluated 16 RCC with features suggestive of MTSCC using chromosomal microarrays.

The cohort was comprised of 8 females and males, each, with an age range of 33–79 years (median, 59), and a tumor size range of 3.4–15.5 cm (median, 5.0). Half the tumors were high-grade (8/16, 50%) with features such as necrosis, marked cytologic atypia, and sarcomatoid differentiation, and 5/16 (31%) were high stage (≥pT3a). Three (of 16, 19%) cases had a predominant (>95%) spindle cell component, whereas 5/16 (31%) were composed of a predominant (>95%) epithelial component. Most cases (12/16, 75%) exhibited a myxoid background and/or extravasated mucin, at least focally.

Twelve (of 16, 75%) cases demonstrated CNA diagnostic of MTSCC (losses of chromosomes 1, 4, 6, 8, 9, 13, 14, 15, and 22). In addition, 2 high-grade tumors showed loss of CDKN2A/B, and gain of 1q, respectively, both of which are associated with aggressive behavior. Three (of 16, 19%) cases, demonstrated nonspecific CNA, and did not meet diagnostic criteria for established RCC subtypes. One (of 16, 6%) low-grade epithelial predominant tumor (biopsy) demonstrated characteristic gains of 7, 17, and loss of Y, diagnostic of PRCC.

MTSCC can be a morphologically heterogenous tumor. Our study validates the detection of characteristic chromosomal CNA for diagnostic use that may be useful in challenging cases with unusual spindle cell or epithelial predominant features, as well as in high-grade tumors.

Aims

Significance of peribiliary capillary plexus (PCP) in gallbladder neoplasms remains unclear. Aims are to characterize high-grade biliary intraepithelial neoplasm (BilIN), pyloric gland adenoma (PGA), and intracholecystic papillary neoplasm (ICPN), precursors of gallbladder carcinoma, and to differentiate invasive carcinoma from pseudo-invasive lesions in gallbladder walls, referring to PCP.

Materials and methods

High-grade BilIN (38 cases), PGA (5 cases), and ICPN (25 cases) were examined using capillary immunostaining. Non-neoplastic gallbladders were used as controls.

Results

In non-neoplastic gallbladders, a single layer of regularly dotted capillaries (PCP) was located beneath lining epithelia and around non-neoplastic glands (NNGs), including Rokitansky-Aschoff sinus (RAS), presenting a two-layer of lining epithelia and PCP. Intra-luminal components of all cases of high-grade BilIN and PGA and one-third of ICPNs presented a two-layer pattern. In the remaining ICPNs, capillaries were irregular and sparse in intraluminal neoplastic components presenting irregular and complicated lesions. Neoplastic glands in gallbladder walls of high-grade BilIN and ICPN were classifiable into 2 types: glands that were underlain by densely dotted capillaries and those that were not, with the latter suggestive of invasive carcinoma, while the former suggestive of non-invasive neoplasms involving NNGs intraepithelially and/or showing an expanding growth into gallbladder wall (pseudo-invasion).

Conclusion

A two-layer pattern of lining epithelia and underlining capillaries were preserved in all cases of high-grade BilIN and PGA and one-third of ICPN cases. Presence or absence of dotted capillaries around neoplastic glands may be able to be added as a new pathologic feature to differentiate invasive carcinomas from pseudo-invasion in gallbladder wall.