Tumoral Intraductal Neoplasms of the Bile Ducts Comprise Morphologically and Genetically Distinct Entities.

CONTEXT.­: Tumoral (grossly visible) intraductal neoplasms of the bile ducts are still being characterized. OBJECTIVE.­: To investigate their morphologic, immunohistochemical, and molecular features. DESIGN.­: Forty-one cases were classified as gastric-, intestinal-, pancreatobiliary-type intraductal papillary neoplasm (IPN), intraductal oncocytic papillary neoplasm (IOPN), or intraductal tubulopapillary neoplasm (ITPN) on the basis of histology. All neoplasms were subjected to targeted next-generation sequencing. RESULTS.­: The mean age at diagnosis was 69 years (42-81 years); male to female ratio was 1.3. Most neoplasms (n = 23, 56%) were extrahepatic/large (mean size, 4.6 cm). The majority (n = 32, 78%) contained high-grade dysplasia, and 68% (n = 28) revealed invasion. All gastric-type IPNs (n = 9) and most ITPNs/IOPNs showed consistent colabeling for CK7/MUC6, which was less common among others (P = .004). Intestinal-type IPNs (n = 5) showed higher rates of CK20 expression than others (P < .001). Overall, the most commonly mutated genes included TP53 and APC, while copy number variants affected ELF3 and CDKN2A/B. All gastric-type IPNs contained an alteration affecting the Wnt signaling pathway; 7 of 9 (78%) showed aberrations in the MAPK pathway. Mutations in APC and KRAS were common in gastric-type IPNs as compared with others (P = .01 for both). SMAD4 was more frequently mutated in intestinal-type IPNs (P = .02). Pancreatobiliary-type IPNs (n = 14) exhibited frequent alterations in tumor suppressor genes including TP53, CDKN2A/B, and ARID2 (P = .04, P = .01 and P = .002, respectively). Of 6 IOPNs analyzed, 3 (50%) revealed ATP1B1-PRKACB fusion. ITPNs (n = 6) showed relatively few recurrent genetic aberrations. Follow-up information was available for 38 patients (median, 58.5 months). The ratio of disease-related deaths was higher for the cases with invasion (56% versus 10%). CONCLUSIONS.­: Tumoral intraductal neoplasms of the bile ducts, similar to their counterparts in the pancreas, are morphologically and genetically heterogeneous.

Stimulated Raman histology facilitates accurate diagnosis in neurosurgical patients: a one-to-one noninferiority study.

OBJECTIVE: Stimulated Raman histology (SRH) offers efficient and accurate intraoperative neuropathological tissue analysis without procedural alteration to the diagnostic specimen. However, there are limited data demonstrating one-to-one tissue comparisons between SRH and traditional frozen sectioning. This study explores the non-inferiority of SRH as compared to frozen section on the same piece of tissue in neurosurgical patients. METHODS: Tissue was collected over a 1-month period from 18 patients who underwent resection of central nervous system lesions. SRH and frozen section analyses were compared for diagnostic capabilities as well as assessed for quality and condition of tissue via a survey completed by pathologists. RESULTS: SRH was sufficient for diagnosis in 78% of specimens as compared to 94% of specimens by frozen section of the same specimen. A Fisher's exact test determined there was no significant difference in diagnostic capability between the two groups. Additionally, both quality of SRH and condition of tissue after SRH were deemed to be non-inferior to frozen section. CONCLUSIONS: This study provides further evidence for the non-inferiority of SRH techniques. It is also the first study to demonstrate SRH accuracy using one-to-one tissue analysis in neuropathological specimens.

Calcifying Pseudoneoplasm of the Neuraxis in the Posterior Fossa: A Case Report and Literature Review.

Calcifying pseudoneoplasm of the neuraxis are rare fibro-osseous lesions that can occur throughout the central nervous system. This paper reports one case of this lesion within the posterior fossa and contains a literature review of all cases documented within the posterior fossa to date. A 53-year-old female patient with a history of epiphora, facial irritation, and headaches was found to have a mass centered in the posterior fossa. The patient underwent surgical resection for removal of the mass. Upon review by pathology, the final diagnosis was consistent with calcifying pseudoneoplasm of the neuraxis.

Intradural Extramedullary Solitary Fibrous Tumor of the Thoracic Spinal Cord.

Solitary fibrous tumors (SFTs) are rare soft tissue neoplasms that can impact the central nervous system (CNS). SFTs comprise <1% of all primary CNS tumors. Here, we describe a rare case of intradural, extramedullary SFT arising within the thoracic spine that was treated with surgical resection. Histological features were evaluated and revealed a highly cellular tumor with positive expression of BCL2, CD34, CD99, and STAT6 proteins that are consistent with a diagnosis of SFT. We discuss the use of surgical intervention for long-term disease control of spinal SFT and evaluate the role of postoperative radiation therapy in management strategies. Lastly, we review the literature reports of intradural, extramedullary SFTs in the thoracic spine. The importance of molecular characterization by histopathology to properly determine diagnosis and prognosis is emphasized.

Adult primary nephrotic syndrome trends by race: a diminished frequency of focal segmental glomerulosclerosis in non-black patients.

PURPOSE: There have been conflicting data on the relative frequency of common forms of primary nephrotic syndrome (PNS). We undertook this study to look at the causes of PNS in the latest decade from our biopsy population, with a special attention to breakdown by race. METHODS: Retrospective chart review of all cases of adult PNS extracted from a database of 1388 cases for the last 10 years. We were careful to exclude patients with secondary disease and without the full nephrotic syndrome. RESULTS: There were 115 cases of PNS. Overall, MN was the most common lesion (40.0%), followed by minimal change disease (MCD) (34.0%), focal segmental glomerulosclerosis (FSGS) (13.0%), and IgA nephropathy (IgAN) (11.3%). Among whites, MN was the most common cause of NS (41.7%), followed by MCD (33.3%), IgAN (16.7%), and FSGS (6.3%). Among blacks, FSGS was the most common lesion (33.3%) followed closely by MN (29.6%), and MCD (26.0%). IgAN was present in 7.4%. Among multiracial patients (MR), MGN was the most common (50%) followed by MCD (45.5%) and FSGS (4.5%). In Asians, MCD (50.1%) and MGN (33.3%) were the most common, followed by FSGS and IgAN with 8.3% each. CONCLUSIONS: MN and MCD were the most common causes of PNS in our population, with FSGS much less common overall. This is especially the case among whites and MR. Among blacks, MN and FSGS were almost codominant causes. The apparent decreased prevalence of FSGS may be related to more effective exclusion of secondary and maladaptive causes.

High EZH2 expression in ductal carcinoma in situ diagnosed on breast core needle biopsy is an independent predictive factor for upgrade on surgical excision.

PURPOSE: Approximately 25 % of DCIS diagnosed on breast core needle biopsy (CNB) is upgraded to invasive carcinoma on surgical excision. Risk factors to predict the upgrade on excision are not well established, leading many patients to be over or under-treated. EZH2 was shown to be associated with aggressive behavior of cancer from many sites, including breast cancer. We aimed to analyze EZH2 expression and tumor infiltrating lymphocytes (TILs) in DCIS as predictive factors for an upgrade on excision. METHODS: We assessed EZH2 expression in 34 DCIS cases diagnosed on CNB and upgraded to invasive carcinoma on excision. Then, we compared these cases with 60 control cases that were not upgraded on excision. A staining score for DCIS (0-12) was obtained by multiplying the staining intensity (0-3) and the percentage of positive cells (1-4). The nuclear staining score ≥6 was considered as 'high' expression. RESULTS: 46 of 94 (49 %) DCIS on CNB showed high EZH2 expression. EZH2 expression was directly correlated with TILs density, nuclear grade, HER2 expression, Ki-67 index and negative ER status. On univariate analysis, upgrade on excision was associated with high EZH2 expression, high TILs density, negative ER status and high Ki-67 index. Multivariate analysis revealed the high EZH2 expression as the only independent predictive factor for upgrade on excision. CONCLUSIONS: Our study revealed the high EZH2 expression as the only independent predictive factor for an upgrade on excision. Future studies should focus on the evaluation of EZH2 expression in tumor-microenvironment interaction in terms of diagnostic, treatment and prognostic purposes.

The normal patella--does it exist? A histologic analysis.

It is unclear if healthy-appearing patellae in patients having total knee arthroplasty (TKA) can be selectively retained. In the study reported here, we hypothesized that grossly normal-appearing patellae in TKA candidates would show significant evidence of microscopic degeneration and thinning of the articular cartilage. Ninety-six consecutive patients (110 knees) with primary degenerative osteoarthritis were recruited from a single institution between November 2010 and June 2011. Thirteen patellae (11 patients) had grossly normal-appearing cartilage. A pathologist measured patellar cartilage thickness in each quadrant and evaluated for evidence of microscopic degenerative change. Mean cartilage thickness was 2.35 mm (range, 1.0-3.0 mm) for superomedial quadrant, 2.31 mm (range, 1.5-3.0 mm) for superolateral quadrant, 2.31 mm (range, 1.0-4.0 mm) for inferomedial quadrant, and 2.62 mm (range, 1.5-3.5 mm) for inferolateral quadrant. Four-point mean (SD) was 2.39 (0.79) mm. Each patella demonstrated at least 2 of the predefined histologic markers of degeneration: fibrillation, fibrosis, chondrocyte proliferation, cyst formation, and fissuring and/or thinning. Even healthy-appearing patellae on gross examination have clear histologic markers of early to moderate articular degeneration. Further comparisons of cartilage thickness using area measurements are needed before the significance of the effect of this deterioration on the technique of selective patellar retention during TKA can be known.

Xanthogranulomatous orchitis in a patient with a history of instrumentation and bacillus Calmette-Guérin therapy.

Xanthogranulomatous orchitis (XGO) is a rare histological finding that is generally diagnosed at orchiectomy. To date, fewer than 10 reports of XGO exist in the literature. The exact pathogenesis of XGO is unknown and patients may present with a rapid onset of symptoms or a longer, more indolent course. We report a patient who presented with symptoms of epididymoorchitis, leukocytosis, and fever after an instillation of bacillus Calmette-Guérin therapy for bladder cancer.