Next-generation sequencing analysis suggests varied multistep mutational pathogenesis for endocrine mucin-producing sweat gland carcinoma with comments on INSM1 and MUC2 suggesting a conjunctival origin.

Endocrine mucin-producing sweat gland carcinoma is a low-grade eyelid tumor. Small biopsies and insensitive immunohistochemistry predispose to misdiagnosis. We aimed to identify clarifying immunohistochemical markers, molecular markers, or both. Clinicopathologic data (22 cases) were reviewed. Immunohistochemistry (insulinoma-associated protein 1, BCL-2, mucin 2 [MUC2], mucin 4, androgen receptor, ß-catenin, and Merkel cell polyomavirus) and next-generation sequencing (Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets, 468 genes) were performed (3 cases). Female patients (n = 15) and male patients (n = 7) (mean age 71.8 years; range 53-88 years) had eyelid or periorbital tumors (>90%) with mucin-containing solid or cystic neuroendocrine pathology. Immunohistochemistry (insulinoma-associated protein 1, BCL2, androgen receptor, retinoblastoma-associated protein 1, and ß-catenin) was diffusely positive (5/5), MUC2 partial, mucin 4 focal, and Merkel cell polyomavirus negative. Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets identified 12 single-nucleotide variants and 1 in-frame deletion in 3 cases, each with DNA damage response or repair (BRD4, PPP4R2, and RTEL1) and tumor-suppressor pathway (BRD4, TP53, TSC1, and LATS2) mutations. Microsatellite instability, copy number alterations, and structural alterations were absent. Insulinoma-associated protein 1 and MUC2 are positive in endocrine mucin-producing sweat gland carcinoma. MUC2 positivity suggests conjunctival origin. Multistep pathogenesis involving DNA damage repair and tumor-suppressor pathways may be implicated.

Fusions involving BCOR and CREBBP are rare events in infiltrating glioma.

BCOR has been recognized as a recurrently altered gene in a subset of pediatric tumors of the central nervous system (CNS). Here, we describe a novel BCOR-CREBBP fusion event in a case of pediatric infiltrating astrocytoma and further probe the frequency of related fusion events in CNS tumors. We analyzed biopsy samples taken from a 15-year-old male with an aggressive, unresectable and multifocal infiltrating astrocytoma. We performed RNA sequencing (RNA-seq) and targeted DNA sequencing. In the index case, the fused BCOR-CREBBP transcript comprises exons 1-4 of BCOR and exon 31 of CREBBP. The fused gene thus retains the Bcl6 interaction domain of BCOR while eliminating the domain that has been shown to interact with the polycomb group protein PCGF1. The fusion event was validated by FISH and reverse transcriptase PCR. An additional set of 177 pediatric and adult primary CNS tumors were assessed via FISH for BCOR break apart events, all of which were negative. An additional 509 adult lower grade infiltrating gliomas from the publicly available TCGA dataset were screened for BCOR or CREBBP fusions. In this set, one case was found to harbor a CREBBP-GOLGA6L2 fusion and one case a CREBBP-SRRM2 fusion. In a third patient, both BCOR-L3MBTL2 and EP300-BCOR fusions were seen. Of particular interest to this study, EP300 is a paralog of CREBBP and the breakpoint seen involves a similar region of the gene to that of the index case; however, the resultant transcript is predicted to be completely distinct. While this gene fusion may play an oncogenic role through the loss of tumor suppressor functions of BCOR and CREBBP, further screening over larger cohorts and functional validation is needed to determine the degree to which this or similar fusions are recurrent and to elucidate their oncogenic potential.

Enhanced cutaneous Rock2 expression as a marker of Rho Kinase pathway activation in autoimmune disease and Kohlemeier-Degos disease.

The small guanosine triphosphatase Rho and its target Rho kinase are involved in a heterogeneous spectrum of cellular activities, many of which are integral to cytoskeletal organization. Furthermore, the Rho kinases result in NF kappa beta activation and hence the induction of various pro-inflammatory cytokines including TNF-alpha, IL-1B and IL-6. ROCK2 is a downstream protein, whose expression is indicative of Rho Kinase activation. Given the diverse effects of Rho-kinase, including a potentially critical role in augmenting inflammation, ROCK2 expression was examined in biopsies of select autoimmune connective tissue diseases as compared to control diagnoses. Select cases of lupus erythematosus, dermatomyositis, autoimmune sclerodermoid disorders and Kohlmeier-Degos disease (a distinctive vasculopathy that occurs in the other aforesaid conditions but also as a forme fruste microvascular and arteriopathic syndrome) were studied. Control biopsies included normal skin and cutaneous inflammatory conditions unrelated to collagen vascular disease/autoimmune disease. We found ROCK2 expression significantly increased in biopsies of lupus erythematosus, dermatomyositis, scleroderma and Kohlmeier-Degos disease. A pattern emerged of consistent marked ROCK2 upregulation in endothelium and variable expression in inflammatory cells and epithelium. While expression was undetectable in normal skin, it was found in inflamed skin unrelated to specific autoimmune disease. The staining pattern could approach that seen in study group cases but was less pronounced and preferentially upregulated in the endothelium, with a lesser extent of staining in the epidermis and inflammatory cells. Rho kinase is a driving factor in diverse cutaneous diseases especially autoimmune disease and Kohlmeier-Degos disease. This significantly upregulated pathway defines a potential target for biologic therapy.

Fatty Acid Synthase and Acetyl-CoA Carboxylase Are Expressed in Nodal Metastatic Melanoma But Not in Benign Intracapsular Nodal Nevi.

BACKGROUND: Melanoma is a potentially lethal form of skin cancer for which the current standard therapy is complete surgical removal of the primary tumor followed by sentinel lymph node biopsy when indicated. Histologic identification of metastatic melanoma in a sentinel node has significant prognostic and therapeutic implications, routinely guiding further surgical management with regional lymphadenectomy. While melanocytes in a lymph node can be identified by routine histopathologic and immunohistochemical examination, the distinction between nodal nevus cells and melanoma can be morphologically problematic. Previous studies have shown that malignant melanoma can over-express metabolic genes such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). This immunohistochemical study aims to compare the utility of FASN and ACC in differentiating sentinel lymph nodes with metastatic melanomas from those with benign nodal nevi in patients with cutaneous melanoma. MATERIALS AND METHODS: Using antibodies against FASN and ACC, 13 sentinel lymph nodes from 13 patients with metastatic melanoma and 14 lymph nodes harboring benign intracapsular nevi from 14 patients with cutaneous malignant melanoma were examined. A diagnosis of nodal melanoma was based on cytologic atypia and histologic comparison with the primary melanoma. All nodal nevi were intracapsular and not trabecular. Immunohistochemistry for Melan-A, S100, human melanoma black 45 (HMB45), FASN, and ACC were performed. The percentage of melanocytes staining with HMB45, FASN, and ACC was determined and graded in 25% increments; staining intensity was graded as weak, moderate, or strong. RESULTS: All metastatic melanomas tested had at least 25% tumor cell staining for both FASN and ACC. Greater than 75% of the tumor cells stained with FAS in 7/13 cases and for ACC in 5/12 cases. Intensity of staining was variable; strong staining for FASN and ACC was observed in 69% and 50% of metastatic melanoma, respectively. HMB45 was negative in 40% of nodal melanoma cases all of which stained with FASN and ACC. Capsular nevi were uniformly negative for FASN, ACC, and HMB45 immunoreactivity. CONCLUSIONS: All metastatic melanoma cases involving sentinel lymph nodes were positive for FASN and ACC while no staining was observed in intracapsular nevi. These findings suggest that FASN and ACC could be used as valuable ancillary stains in the distinction between nodal nevi and metastatic melanoma.

A Novel Variant t(1;22) Translocation - ins(22;1)(q13;p13p31) - in a Child with Acute Megakaryoblastic Leukemia.

BACKGROUND The reciprocal translocation t(1;22)(p13;q13) involving the RBM15 and MKL1 genes is an uncommon abnormality that occurs in a subset of acute myeloid leukemia with megakaryocytic differentiation (AMKL). Variant translocations have been infrequently described in this subtype of leukemia. CASE REPORT We describe the case of a 3-month-old girl who presented with progressive abdominal distension, vomiting, and fever. Although there was no morphologic evidence of leukemia in the bone marrow, cytogenetic and metaphase fluorescence in situ hybridization analysis identified an insertion of p13p31 bands of chromosome 1 onto the long arm of chromosome 22, resulting in the karyotype: 46,XX,ins(22;1)(q13;p13p31). Subsequent liver biopsy demonstrated extensive involvement by AMKL. CONCLUSIONS AMKL can present with fewer than 20% blasts in the peripheral blood or bone marrow, necessitating careful evaluation for extramedullary disease. In other situations, bone marrow fibrosis can result in difficult marrow aspirations and a falsely decreased blast count. This case report highlights the critical role of careful cytogenetic and FISH testing in the diagnosis of AMKL.

Utility of Genomic Analysis in Differentiating Synchronous and Metachronous Lung Adenocarcinomas from Primary Adenocarcinomas with Intrapulmonary Metastasis.

Distinguishing synchronous and metachronous primary lung adenocarcinomas from adenocarcinomas with intrapulmonary metastasis is essential for optimal patient management. In this study, multiple lung adenocarcinomas occurring in the same patient were evaluated using comprehensive histopathologic evaluation supplemented with molecular analysis. The cohort included 18 patients with a total of 52 lung adenocarcinomas. Eleven patients had a new diagnosis of multiple adenocarcinomas in the same lobe (n=5) or different lobe (n=6). Seven patients had a history of lung cancer and developed multiple new tumors. The final diagnosis was made in resection specimens (n=49), fine needle aspiration (n=2), and biopsy (n=1). Adenocarcinomas were non-mucinous, and histopathologic comparison of tumors was performed. All tumors save for one were subjected to ALK gene rearrangement testing and targeted Next Generation Sequencing (NGS). Using clinical, radiologic, and morphologic features, a confident conclusion favoring synchronous/metachronous or metastatic disease was made in 65% of patients. Cases that proved challenging included ones with more than three tumors showing overlapping growth patterns and lacking a predominant lepidic component. Genomic signatures unique to each tumor were helpful in determining the relationship of multiple carcinomas in 72% of patients. Collectively, morphologic and genomic data proved to be of greater value and achieved a conclusive diagnosis in 94% of patients. Assessment of the genomic profiles of multiple lung adenocarcinomas complements the histological findings, enabling a more comprehensive assessment of synchronous, metachronous, and metastatic lesions in most patients, thereby improving staging accuracy. Targeted NGS can identify genetic alterations with therapeutic implications.

Diagnostic yield of cytopathology in evaluating pericardial effusions: Clinicopathologic analysis of 419 specimens.

BACKGROUND: Pericardial effusions can cause considerable morbidity and potentially may lead to mortality. Malignant pericardial effusions are uncommon, and data on malignancies encountered in pericardial effusion cytology specimens are limited. METHODS: Relevant records of all pericardial effusions from January 2008 to September 2014 were examined and compared with pericardial biopsy results when performed. Discrepant cases were reviewed to determine the cause of the disagreement. RESULTS: In total, 419 pericardial effusion specimens obtained from 364 patients were examined. Cytologic diagnostic categories included: negative for malignancy (332 specimens; 79%), equivocal (25 specimens; 6%), and positive (62 specimens from 51 patients; 15%). Forty-seven patients who had positive effusions were known to have malignancy. The most common primary malignancies were breast (39.3%) and lung (39.3%) cancers in women and lung cancer (47.4%) in men. A concurrent pericardial biopsy was performed in 46% of patients. Excluding equivocal cytologic diagnoses, cytology and biopsy were concordant in 153 of 173 paired samples (88.4%). The sensitivity of cytology in diagnosing malignancy was 92.1% compared with 55.3% for pericardial biopsy. CONCLUSIONS: Cytologic examination has significant diagnostic utility in the evaluation of pericardial effusions and exhibits a lower false-negative rate compared with pericardial biopsy. Submission of pericardial biopsy alongside effusion cytology is associated with increased sensitivity for detecting malignancy and may be especially useful in the setting of low-volume pericardial effusion. Cancer Cytopathol 2017;125:128-137. © 2016 American Cancer Society.

Cutaneous Lymphadenoma: A Trichoblastoma with Regressive Inflammatory Changes.

The authors address the entity of cutaneous lymphadenoma. Although considered benign, cutaneous lymphadenoma can be easily misdiagnosed as basal cell carcinoma because of its close clinical and histological resemblance. This entity is rare and controversial both in terms of its histogenesis and the various diagnostic terms assigned to it throughout the literature. While rare, cutaneous lymphadenoma should be considered in the differential of any facial nodule or papule in addition to the more common basal cell carcinoma, nevi, cysts, and appendiceal tumors.

Folliculocentric Herpes: A Clinicopathological Study of 28 Patients.

BACKGROUND: The cutaneous manifestations of herpes infection are primarily in the context of active infection and of the post-herpetic zosteriform eruption. The former manifests cytopathic alterations diagnostic of herpes. The latter includes lichen planus-like and granuloma annulare-like eruptions and lymphocytoma cutis. METHODS: We encountered skin biopsies from 28 patients whose acute or chronic herpetic or post-herpetic zosteriform lesions manifested folliculocentricity. The clinical appearance of the lesions was correlated with the histopathologic and immunohistochemical features of paraffin-embedded skin biopsies to determine the specific viral etiology. A history of underlying medical disease was noted if present. RESULTS: There were 16 men and 12 women with a folliculocentric eruption occurring after a known herpetic eruption or manifesting cytopathic changes and/or immunohistochemical findings compatible with herpes virus in lesional skin biopsies. Underlying immune dysregulatory states were present in most cases, namely, malignancy, anticonvulsant or antidepressant therapy, diabetes mellitus, psoriasis, Crohn disease, and other conditions. All biopsies demonstrated dense lymphohistiocytic infiltrates in or around hair follicles with variable necrosis, while active infections also showed cytopathic and/or immunohistochemical evidence of herpetic alterations, most commonly varicella zoster. Other features included interfollicular interface dermatitis, lymphocytic eccrine hidradenitis, neuritis, and folliculocentric vasculitis. CONCLUSIONS: Cutaneous herpetic eruptions can evoke a predominantly folliculocentric mononuclear cell reaction and vasculitis; there is an association with underlying endogenous and/or iatrogenic immune dysregulation. Most cases are secondary to reactivation of varicella zoster. The histomorphology suggests a role for cell-mediated immunity. Antigenic homology of an endogenous 72-kd heat shock protein in follicles with that of a herpetic heat shock protein, in concert with an intrafollicular proliferative response of γ-δ T lymphocytes, may explain the follicular localization and composition of the infiltrate.

Dermatofibrosarcoma Protuberans-Like Tumor With COL1A1 Copy Number Gain in the Absence of t(17;22).

A 57-year-old woman presented with a 3-year history of a progressive firm plaque on the right cheek. Skin biopsies revealed a bland, storiform, spindle-cell proliferation involving the deep dermis and subcutaneous fat. By immunohistochemistry, the tumor cells were diffusely positive for CD34 and caldesmon with multifocal reactivity for epithelial membrane antigen and focal, weak staining for smooth muscle actin. Retinoblastoma protein expression was not detectable in tumor cells by immunohistochemistry. An interphase fluorescence in situ hybridization analysis for platelet-derived growth factor B (PDGFB) gene rearrangement was negative. A single-nucleotide polymorphism array study detected 1) a gain of chromosome segment 17q21.33-q25.3 which overlapped the entire COL1A1 gene with a breakpoint at 17q21.33, approximately 250 Kb centromeric to the 3' end of COL1A1 gene, 2) several segmental gains on chromosome 11, and 3) an RB1 gene locus with normal copy number and allele frequency. Although the current case resembles dermatofibrosarcoma protuberans, it is unique in that it demonstrates a copy number gain of chromosome 17q in the absence of fusion of COL1A1 and PDGFB genes and an unusual immunohistochemical staining profile. The morphologic and molecular findings suggest a novel molecular variant of dermatofibrosarcoma protuberans not detectable with standard fluorescence in situ hybridization for PDGFB rearrangement. This variant appears to respond to imatinib after 9 months of follow-up.

Imaging findings of spinal brown tumors: a rare but important cause of pathologic fracture and spinal cord compression.

Brown tumors rarely develop in the spine, and neurological compromise is exceedingly uncommon. There is a growing body of literature describing brown tumors that involve the spine, but few emphasize the radiographic findings. In the present case, we illustrate the development and progression of biopsy-proven brown tumors leading to neurological compromise through radiographs, computed tomography, magnetic resonance, and nuclear imaging acquired over a 4-year span.

Granulomatous Insulitis as a Cause of Acute-Onset Insulin-Dependent Diabetes Mellitus in a Patient With a Pancreatic Endocrine Carcinoma.

Autoimmune destruction of ß cells is the cause of most cases of type 1 diabetes mellitus. Lymphocytic insulitis has been documented in the early phases of this disease as well as in recurrent diabetes after pancreas transplantation and in certain viral infections. We report a unique case of granulomatous insulitis in a patient with an endocrine tumor of the pancreas that clinically manifested as acute-onset insulin-dependent diabetes mellitus. Granulomata were present in islets with complete disappearance of ß cells, as well as in the primary tumor, metastases, and lymph nodes. We postulate that these granulomata represent a sarcoid-like reaction to the tumor with secondary injury to nonneoplastic endocrine cells through a mechanism of molecular mimicry.

Evaluating the cause of death in obese individuals: a ten-year medical autopsy study.

BACKGROUND: Obesity is a growing public health problem associated with increased morbidity and rate of death. Postmortem examination is imperative to determine the cause of death, to detect clinically unsuspected disease entities, and consequently to determine the actual impact of obesity on patient mortality. METHODS: A total of 849 adult autopsies were retrospectively reviewed. Obese (BMI ≥ 30 kg/m(2)) and nonobese patients were separately studied. The primary cause of death in each group was categorized into malignancy, infection, stroke, ischemic and nonischemic heart disease, pulmonary embolism, hemorrhage, and primary nonneoplastic diseases of different organ systems. RESULTS: Of 849 autopsies, 32.3% were obese. The leading causes of death in the obese population were malignancy (31.4%), infection (25.9%), ischemic heart disease (12.8%), and pulmonary embolism (6.2%). Obese individuals were statistically more likely to die from pulmonary embolism and liver disease and less likely to die from neurologic diseases and nonischemic heart disease. CONCLUSION: Autopsies on obese individuals constitute a third of all adult medical autopsies in our center. Increased death rates in the obese due to pulmonary embolism and liver disease should receive special clinical attention. Autopsy findings in the obese population should contribute to overall premortem disease detection, prevention, and management.

Comparing BRAF mutation status in matched primary and metastatic cutaneous melanomas: implications on optimized targeted therapy.

BACKGROUND: Selective BRAF inhibitors have shown dramatic results with regard to improving outcome in patients with melanoma. Testing the BRAF status in matched primary and metastatic melanomas to optimize individual targeted therapy is not well investigated. METHODS: Extended BRAF testing using PCR for 9 mutations and VE1 immunohistochemistry for BRAF V600E detection on 95 lesions including 40 primary melanomas with their matched metastases (n = 42), recurrences (n = 9) and second primaries (n = 4) was performed. Nine patients had multiple metastases. RESULTS: V600E was the only identified mutation type; 35.4% of primary vs. 18.9% of metastatic melanomas. The overall primary-metastatic BRAF status discordance rate was 32.3% using PCR and 27.5% with immunohistochemistry, and was significantly more frequent in primary lesions with mutant BRAF (67%). Males and patients with metastasis to lymph nodes were less likely to be discordant compared to females and those with metastasis to other sites (p = 0.023). Discordant BRAF mutation status was predicted by multivariate binary logistic regression: the presence of a mutant BRAF in the primary melanoma [OR (95% C.I.) = 23.4 (2.4-229.7)] and female gender [OR = 10.6 (1.08-95)]. Inter-metastases BRAF concordance was 100% (6 comparisons). CONCLUSION: A high discordant rate implies the need for clinical trials addressing the response to targeted therapy in patients with discordant BRAF statuses between their primary and metastatic lesions.

A collaborative nationwide lymphoma study in Lebanon: incidence of various subtypes and analysis of associations with viruses.

Incidence of various Hodgkin (HL) and non-Hodgkin lymphoma (NHL) subtypes and association with viruses in Lebanon are not known. We undertook a nationwide study of 272 patients diagnosed with lymphoma in 2007. HL comprised 32.7 % (n = 89) of cases while NHL represented 67.3 % (n = 183). Consistent with the literature, nodular sclerosis was the most predominant HL subtype (n = 57/89). Among NHL, B-cell NHL represented 88 % (n = 161/183), T-cell NHL 9 % (n = 17/183), whereas in 2.7 % it was not classifiable. The B-cell NHL comprised predominantly diffuse large B-cell lymphoma (46 %) and follicular lymphoma (23 %). 81 cases were reviewed by a panel of pathologists with 87.6 % concordance rate. Serology was negative for hepatitis C in 122 tested cases. HIV was positive in 2 cases. Two adult T-cell leukemia/lymphoma were HTLV-I positive. EBV IgG were positive in 88.5 % of cases. 38 EBV seropositive cases [27 NHL (24 B-cell, 3 T-cell) and 11 HL] were studied for EBV genome expression using EBV-encoded RNA (EBER)-in situ hybridization. EBER expression was positive in 8 (21 %) cases (6 HL, 2 T-cell NHL). The distribution of lymphoma subtypes in Lebanon appears similar to that of Western countries. The high rate of EBV positivity in HL and T-cell lymphoma by EBER deserves further investigation.

Cutaneous leishmaniasis mimicking inflammatory and neoplastic processes: a clinical, histopathological and molecular study of 57 cases.

BACKGROUND: Cutaneous leishmaniasis displays considerable variation in its histopathological and clinical presentation. Clinically, it progresses from a papule into a painless ulcerated and crusted nodule/papule. Microscopically, it progresses from sheets of amastigote-filled histiocytes to granulomatous inflammation. METHODS: The study was conducted on 145 skin biopsies from untreated patients with histopathological and/or clinical suspicion of cutaneous leishmaniasis in Lebanon, Syria and Saudi Arabia (1992-2010). The pre-biopsy clinical diagnosis and demographic data were collected. Biopsies were evaluated for the major microscopic pattern, and the parasitic index (PI) was also determined. Diagnosis was confirmed by polymerase chain reaction (PCR) followed by molecular sub-speciation. RESULTS: Of the 145 patients, 125 were confirmed as cutaneous leishmaniasis by PCR. Eighteen cases presented with a pre-biopsy clinical diagnosis other than cutaneous leishmaniasis that ranged from dermatitis to neoplasm. Of the 125 cases, 57 showed a major histopathological pattern other than cutaneous leishmaniasis. Identification of amastigotes was equivocal (PI ≤1) in 38 of the 57 cases. Of interest, all the 18 cases with a pre-biopsy clinical diagnosis other than cutaneous leishmaniasis also showed atypical histopathology for cutaneous leishmaniasis. CONCLUSIONS: The manifestations of cutaneous leishmaniasis are broad and may mimic other inflammatory and neoplastic diseases. Pathologists and dermatologists should be aware of such pitfalls and can utilize PCR to confirm the diagnosis of leishmaniasis.

Peri-ampullary mixed acinar-endocrine carcinoma.

Mixed acinar-endocrine carcinomas (MAEC) are rare tumors of the pancreas. We present the case of a patient with periampullary tumor that presented with painless jaundice and after investigation was found to have MAEC. He underwent pancreaticoduo-dunectomy with tumor free margins and negative lymph nodes. The patient presented with local recurrence and liver metastasis after 1 year and is on chemotherapy with stable lesions 30 months after the diagnosis.