Invasive squamous cell carcinoma within a plaque of circumscribed palmar hypokeratosis.

Circumscribed palmar hypokeratosis (CPH) is a localized disorder of epidermal keratinization that is presented as a well-delimited, depressed, erythematous plaque on the palms or on the soles. It is histopathologically characterized by an abrupt thinning of the corneal epidermal layer. CPH is considered a benign condition, but a few cases with dysplastic changes/carcinoma in situ in the hypokeratotic epidermis have been described. We report hereby a case of invasive squamous cell carcinoma developed within a plaque of CPH. The pathogenesis of the malignant changes in this disorder remains to be clarified. Clinicians should be aware of the potential for developing malignancy in CPH and carry out a closer follow-up of this disorder.

Cutaneous leishmaniasis: A pathological study of 360 cases with special emphasis on the contribution of immunohistochemistry and polymerase chain reaction to diagnosis.

BACKGROUND: Traditional methods for the diagnosis of leishmaniasis yield poor sensitivity, which limits its effectiveness in lesions with a low parasite burden. METHODS: Retrospective pathologic study of 360 cases of cutaneous leishmaniasis and analysis of the different diagnostic methods used. RESULTS: In 93% of the lesions, histopathology showed a dense and diffuse inflammatory infiltrate, consisting of lymphocytes, histiocytes and plasma cells, which occupied the superficial and mid dermis and variably extended to deep dermis and superficial subcutis (standard pattern). The remaining cases exhibited atypical features, such as perivascular, interstitial or perifollicular inflammatory patterns, folliculitis or panniculitis. Granulomas were identified in 84% of biopsies, most of them as small, poorly formed, non-necrotizing histiocytic aggregates. Amastigotes were visualized by routine histopathologic exam in 36% of biopsies. Immunohistochemistry stained 17 of 26 lesions (65%) negative by conventional stains. PCR provided the correct diagnosis in 218 cases (58% of the series) negative for Leishmania by other techniques. CONCLUSIONS: Biopsies negative for Leishmania by traditional diagnostic methods that show the histopathologic standard pattern, those with atypical features from patients with clinical suspicion of cutaneous leishmaniasis in endemic areas, should be studied by immunohistochemistry and/or PCR for Leishmania in order to reach the definitive diagnosis.

High-risk Human Papillomavirus Determination in Formalin-fixed, Paraffin-embedded Cervical Tissue Using the Roche Cobas 4800 System: A Comparative Study With Liquid-based Cytology.

Roche cobas 4800 human papillomavirus (HPV) test is an automated real-time polymerase chain reaction-based system that allows the simultaneous detection of 14 human papillomavirus high-risk (HR-HPV) genotypes. This test is Food and Drug Administration approved since 2011 for HPV determination in liquid-based cytologic samples, but a clinically validated technique for formalin-fixed, paraffin-embedded (FFPE) tissue specimens is presently not commercially available. In our laboratory, we have developed an HPV detection procedure in FFPE tissue by cobas 4800 HPV test. In order to validate our method, we retrospectively studied 165 FFPE cervical biopsy and conization specimens with varied diagnoses from our files. In 50 of them, we contrasted the results with those obtained from simultaneous liquid-based cytologies from the same patients. Finally, seeking the possible complementary clinical usefulness of the procedure, we compared the HPV genotypes detected in cervical intraepithelial neoplasia grade 1 (CIN1)-diagnosed biopsies from 20 patients with a subsequent high-grade CIN (CIN2+) diagnosis with those from another group of 20 patients without a subsequent CIN2+ diagnosis. Eighty-seven percent of the assays provided informative results. HR-HPV was detected in 28 of 32 (88%) invasive cervical squamous carcinomas. Coincidental HR-HPV genotypes were obtained in 32 of 50 (64%) cases with simultaneous cervical biopsy and liquid-based cytologic samples. A significant higher risk of progression to CIN2+ was found when HPV16 (P=0.022) or any HR-HPV genotype (P=0.037) was detected in CIN1 biopsies. The reported procedure provides an automated, technically time-saving, easy to integrate into laboratory routine, and reliable method of HR-HPV determination in FFPE specimens.

Solitary Fibrous Tumor of the Vulva: Report of 2 Cases, Including a De Novo Dedifferentiated Solitary Fibrous Tumor Diagnosed After Molecular Demonstration of NAB2-STAT6 Gene Fusion.

Solitary fibrous tumor (SFT) is a neoplasm of fibroblastic lineage that has been documented in almost every anatomic location. Vulval SFT is very rare with only 10 cases reported to date. We present 2 additional SFTs located in the vulva, in adult women of 59 and 25 yr of age. The first showed a classic morphology and immunophenotype with uniform and strong STAT6 nuclear expression. The other one was a spindle-cell de novo dedifferentiated SFT with heterogeneous nuclear and cytoplasmic STAT6 staining, which could only be correctly diagnosed after molecular analysis with demonstration of a NAB2-STAT6 gene fusion. This genetic aberration is considered to represent the major pathogenic driver in SFT and is highly specific for this neoplasm. The differential diagnosis of vulval SFT is wide and varies depending on the histologic SFT subtype. Molecular analysis is mandatory for a correct diagnosis in cases without the characteristic histopathologic and immunophenotypical features.

[Protocol for the study of bone tumours and standardization of pathology reports]. / Protocolo para el estudio de muestras y estandarización del informe patológico de tumores óseos.

Primary bone neoplasms represent a rare and heterogeneous group of mesenchymal tumours. The prevalence of benign and malignant tumours varies; the latter (sarcomas) account for less than 0.2% of all malignant tumours. Primary bone neoplasms are usually diagnosed and classified according to the criteria established and published by the World Health Organization (WHO 2013). These criteria are a result of advances in molecular pathology, which complements the histopathological diagnosis. Bone tumours should be diagnosed and treated in referral centers by a multidisciplinary team including pathologists, radiologists, orthopedic surgeons and oncologists. We analyzed different national and international protocols in order to provide a guide of recommendations for the improvement of pathological evaluation and management of bone tumours. We include specific recommendations for the pre-analytical, analytical, and post-analytical phases, as well as protocols for gross and microscopic pathology.

Protocolo de estudio y estandarización del informe patológico de los tumores de partes blandas malignos y de comportamiento intermedio de adolescentes y adultos / Investigation protocol and standardization of pathology reports for soft tissue tumours with intermediate malignant potential in adolescents and adults

Los sarcomas de partes blandas son neoplasias poco frecuentes, que incluyen una amplia variedad de tipos histológicos, se presentan en cualquier localización y muestran una gran heterogeneidad, con solapamiento, en ocasiones, de la morfología de tumores con comportamiento clínico y biológico muy diverso. El diagnóstico es a menudo complejo, resultando necesarias guías que consensúen criterios que permitan homogeneizar la información, la terminología y la clasificación entre los diferentes centros. Basándonos en protocolos de otras sociedades científicas y en una revisión actualizada de la literatura, miembros del Club de Partes Blandas de la SEAP hemos elaborado este documento, en el que se revisan las diferentes fases del estudio de los sarcomas de partes blandas en los servicios de patología y se definen los datos fundamentales a incluir en los informes de estos tumores (AU)

Soft tissue sarcomas are infrequent neoplasms that include a wide variety of histological types. They may present in any location and show a great morphological heterogeneity; indeed, they may have similar characteristics to tumours with diverse clinical and biological behaviour, making their diagnosis difficult. Thus, guidelines are required in order to unify the information, terminology and classification from different diagnostic centres. Several members of the SEAP Soft Tissue Pathology Club have created a document based on protocols from other scientific societies and on an updated review of the literature. The protocol includes the different phases of the study of soft tissue sarcomas in the pathology department and aims to define the data that should be included in the final pathology reports (AU)

Protocolo para el estudio de muestras y estandarización del informe patológico de tumores óseos / Protocol for the study of bone tumours and standardization of pathology reports

Las neoplasias primarias de hueso representan un grupo poco frecuente y heterogéneo de tumores mesenquimales con diferente prevalencia entre los benignos y los malignos o sarcomas (que suponen menos del 0,2% de todos los tumores malignos). Habitualmente se diagnostican y clasifican según los criterios establecidos y publicados por la Organización Mundial de la Salud (OMS 2013), en continua evolución como resultado de los avances en patología molecular y citogenética, que pueden complementar el diagnóstico. El diagnóstico y tratamiento de estos tumores debe realizarse en centros de referencia, con un abordaje multidisciplinar que incluya patólogos, radiólogos, cirujanos ortopédicos y oncólogos. Para elaborar esta revisión se han analizado diferentes protocolos nacionales e internacionales. Pretende servir como una guía de recomendaciones que ayuden a mejorar el manejo y la evaluación patológica de las neoplasias óseas en nuestro medio. Se describen las fases preanalítica, analítica y postanalítica y los protocolos macro y microscópico (AU)

Primary bone neoplasms represent a rare and heterogeneous group of mesenchymal tumours. The prevalence of benign and malignant tumours varies; the latter (sarcomas) account for less than 0.2% of all malignant tumours. Primary bone neoplasms are usually diagnosed and classified according to the criteria established and published by the World Health Organization (WHO 2013). These criteria are a result of advances in molecular pathology, which complements the histopathological diagnosis. Bone tumours should be diagnosed and treated in referral centers by a multidisciplinary team including pathologists, radiologists, orthopedic surgeons and oncologists. We analyzed different national and international protocols in order to provide a guide of recommendations for the improvement of pathological evaluation and management of bone tumours. We include specific recommendations for the pre-analytical, analytical, and post-analytical phases, as well as protocols for gross and microscopic pathology (AU)

[Atypical leiomyoma in a patient with cutaneous leiomyomatosis and mutation of the enzyme fumarate hydratase]. / Leiomioma cutáneo atípico en un paciente con leiomiomatosis cutánea y mutación de la enzima fumarato hidratasa.

We report the case of a 56 year-old male with an atypical leiomyoma in the context of a cutaneous leiomyomatosis and a family history of uterine leiomyomatosis. The genetic study revealed a mutation in the gene for the enzyme fumarate hydratase, but he has not had any renal malignancy so far. Atypical leiomyoma is a rare tumor that usually presents as a single lesion and is exceptional in patients with cutaneous leiomyomatosis. The relation between fumarate hydratase enzyme mutations with multiple leiomyomas, uterine leiomyomatosis and an increased risk of developing kidney cancer is widely known. However, the role of these mutations in the development of atypical leiomyomas is still impossible to clarify given the few cases reported in the literature.

Defining Ewing and Ewing-like small round cell tumors (SRCT): The need for molecular techniques in their categorization and differential diagnosis. A study of 200 cases.

BACKGROUND: Differentiation of Ewing sarcoma family of tumors (ESFT) and Ewing-like tumors remains problematic. Certain ESFT with morphological and immunohistochemical (IHC) profiles lack the EWSR1-ETS transcript. To improve diagnostic accuracy we investigated the presence of several specific transcripts in 200 small round cell tumors (SRCT) displaying ESFT morphology and immunophenotype in which EWSR1 FISH analysis was non-informative or negative. DESIGN: 200 tumors (formalin-fixed, paraffin-embedded) were analyzed by RT-PCR. All tumors were tested for EWSR1-ETS, EWSR1/WT1, PAX3/7-FOX01 or SYT/SSX transcripts, and the negative tumors were subsequently analyzed for CIC/DUX4, BCOR/CCNB3 and CIC/FOX04 transcripts. RESULTS: 133 (66.5%) ESFT displayed one of the above EWSR1-ETS translocations. Three cases (1.5%) revealed the SYT-SSX transcript for Synovial sarcoma, and one (0.5%) a EWSR1-WT1 transcript for Desmoplastic Small Round Cell tumor. The CIC-DUX4 translocation was found in six Ewing-like tumors (3%) with CD99 positivity. The BCOR-CCNB3 gene fusion was observed in 5 tumors (2.5%) displaying round or spindle cells with strong CCNB3 IHC expression in 3 tumors. Moreover, RT-PCR failed to detect any gene fusion transcripts in 19 tumors (9.5%) and were considered "undifferentiated small round cell sarcoma" (SRCS). Molecular biology results were non-informative in 33 SRCTs (16.5%) due to RNA degradation through inadequate fixation and/or decalcification. CONCLUSION: Our analysis of 200 SRCTs confirms the molecular heterogeneity of neoplasms with ESFT morphology and highlight that molecular studies with RT-PCR including new emerging gene fusion transcripts are mandatory for the diagnosis when EWSR1 FISH is negative or non-informative. The incidence of CIC-DUX4, BCOR-CCNB3 and CIC-FOX04 transcripts was relatively low. A small group of Ewing-like sarcomas or undifferentiated SRCS remains unclassified. Adopting appropriate tissue fixation and processing protocols is important to avoid degradation of fixed/embedded tissue when no frozen tumor is available.

Cytological Diagnosis of Bilateral Breast Implant-Associated Lymphoma of the ALK-Negative Anaplastic Large-Cell Type. Clinical Implications of Peri-Implant Breast Seroma Cytological Reporting.

The cytological examination of peri-prosthetic breast effusions allowed the diagnosis of bilateral breast-implant ALK-negative anaplastic large cell lymphoma (BI-ALCL) in the case reported. Ten years after reconstructive surgery with bilateral breast implants, a large unilateral seroma developed and was cytologically analyzed. The presence of CD30 and CD4-positive large-sized atypical lymphoid cells exhibiting horseshoe-shaped nuclei and a brisk mitotic activity rendered the diagnosis of BI-ALCL. Similar cells were seen in the peri-prosthetic fluid intraoperatively collected from the contralateral breast. Although initial histological analysis of the capsulectomy specimens showed unilateral tumor, the cytological findings prompted a more thorough tissue sampling, resulting in the diagnosis of bilateral disease. BI-ALCL usually follows an indolent clinical course; however, there are reported cases with an aggressive behavior. While the presence of bilateral disease is a putative risk factor for a bad prognosis, the small number of cases reported precludes a definitive assessment of this risk. Since most BI-ALCL present with late seromas, cytologic analysis of these effusions in women with breast implants should be mandatory. Cytology is a safe tool for diagnosis and follow-up of patients with breast implant-related late seromas, sometimes proven more sensitive than histological analysis. Complete bilateral capsulectomy and a detailed histological analysis should follow a cytological diagnosis of BI-ALCL in a breast effusion in order to avoid false negative diagnoses. Our case constitutes the first published report of a bilateral BI-ALCL diagnosed by cytology. Diagn. Cytopathol. 2016;44:623-627. © 2016 Wiley Periodicals, Inc.

Leiomioma cutáneo atípico en un paciente con leiomiomatosis cutánea y mutación de la enzima fumarato hidratasa / Atypical leiomyoma in a patient with cutaneous leiomyomatosis and mutation of the enzyme fumarate hydratase

Se presenta un varón de 56 años con un leiomioma atípico en el contexto de una leiomiomatosis cutánea, con antecedentes familiares de miomatosis uterina y con estudio genético que revela una mutación en el gen de la enzima fumarato hidratasa, sin que hasta el momento presente ningún tipo de neoplasia maligna renal. El leiomioma atípico es un tumor poco frecuente, que usualmente ocurre de forma aislada, siendo excepcional la presentación en pacientes con leiomiomatosis cutánea. Es ampliamente conocida la relación de la mutación de la enzima fumarato hidratasa con leiomiomas mútiples, miomas uterinos y el mayor riesgo de desarrollar cáncer renal; sin embargo, el papel de esta mutación en el desarrollo de leiomiomas atípicos es por hoy imposible de esclarecer debido a los escasos casos recogidos en la literatura.

We report the case of a 56 year-old male with an atypical leiomyoma in the context of a cutaneous leiomyomatosis and a family history of uterine leiomyomatosis. The genetic study revealed a mutation in the gene for the enzyme fumarate hydratase, but he has not had any renal malignancy so far. Atypical leiomyoma is a rare tumor that usually presents as a single lesion and is exceptional in patients with cutaneous leiomyomatosis. The relation between fumarate hydratase enzyme mutations with multiple leiomyomas, uterine leiomyomatosis and an increased risk of developing kidney cancer is widely known. However, the role of these mutations in the development of atypical leiomyomas is still impossible to clarify given the few cases reported in the literature.

Clear Cell Atypical Fibroxanthoma: Clinicopathological Study of 6 Cases and Review of the Literature With Special Emphasis on the Differential Diagnosis.

Atypical fibroxanthoma (AFX) is an uncommon dermal-based neoplasm arising on the sun-damaged skin of elderly people. Clear cell AFX is a rare variant with only 12 cases reported until the present date, all of them as case reports, except for 1 small series of 3 cases. The authors report 6 new cases and review the literature with special emphasis on the differential diagnosis. The clear cell variant represents 5% of AFX from their files. Histopathologically, it consists of sheets of epithelioid, pleomorphic cells, intermixed with a varying number of giant multinucleated and spindle cells, the latter arranged in a fascicular pattern. All cell types predominantly exhibit a clear, microvacuolated cytoplasm with well-demarcated cell borders. The clinical and immunohistochemical features of this variant are similar to those of the classic type. Clear cell AFX must be differentiated from other cutaneous clear cell neoplasms, some of them with an aggressive clinical behavior, including clear cell melanoma, primary cutaneous and metastatic clear cell carcinomas, clear cell sarcoma, pleomorphic liposarcoma, tumor of perivascular epithelioid cells, and distinctive dermal clear cell mesenchymal neoplasm. The clinical presentation and immunohistochemical profile play a key role in the differential diagnosis.

Pleomorphic dermal sarcoma: a more aggressive neoplasm than previously estimated.

BACKGROUND: Pleomorphic dermal sarcoma (PDS) is a rare neoplasm sharing pathological features with atypical fibroxanthoma, but adding tumor necrosis, invasion beyond superficial subcutis or vascular or perineural infiltration. Although its metastatic risk has been estimated to be less than 5%, its real outcome is presently uncertain because of its rarity and to the lack of homogeneous criteria used in reported cases. METHODS: Retrospective clinicopathological study of 18 cases of PDS. RESULTS: The lesions presented as tumors or plaques (size: 7-70 mm) on the head of elderly patients (median: 81 years), without a gender predominance. Histopathologically, they consisted of spindle cells arranged in a fascicular pattern, containing pleomorphic epithelioid and giant multinucleated cells in varying proportions, and usually exhibiting numerous mitotic figures and infiltrative tumor margins. No immunoexpression for cytokeratins, S100 protein, desmin or CD34 was observed. Necrosis and venous invasion were found in three tumors each (17%). Follow-up was available in 15 cases (median: 33 months). Three patients (20%) had local recurrences, all with incomplete primary surgical resections. Three patients (20%) developed distant metastases in the skin, regional lymph nodes and/or lungs and died from the disease. CONCLUSION: Our data suggest that PDS may be a more aggressive neoplasm than previously estimated.

Fibromyxoid nephrogenic adenoma protruding in a renal cortical cyst. A rare morphological variant in an outstanding location.

Nephrogenic adenoma (NA) is an unusual, benign lesion of the urinary tract, generally presenting in the bladder and with less frequency in the renal pelvis, urethra or ureter. It consists of tubules, microcysts and papillae lined by a single layer of low cuboidal epithelium without atypia. Recently, a fibromyxoid variant mimicking an infiltrating mucinous adenocarcinoma has been described. We report hereby the case of a 70-year-old female with a fibromixoid NA protruding in a renal cortical cyst. Only one case of NA in a renal cortical cyst has been found in the literature and it was of the classical type. The development of a NA in a renal cortical cyst lends support to the theory that the NA results from proliferation of secondarily implanted exfoliated renal epithelial cells.

Ewing-like sarcoma with CIC-DUX4 gene fusion in a patient with neurofibromatosis type 1. A hitherto unreported association.

Sarcoma with CIC-DUX4 gene fusion is emerging as the most prevalent subset of Ewing-like undifferentiated small round cell sarcomas with around 50 cases published. We report hereby the case of a 40-year-old male who presented a CIC-DUX4 sarcoma in deep soft tissues in his thigh. He had been diagnosed with neurofibromatosis type 1 at age 19 and over the years underwent resection of multiple neural neoplasms, including two malignant peripheral nerve sheath tumors with classical spindle-cell histopathology. The CIC-DUX4 sarcoma was treated with surgical resection, radiation and chemotherapy, but lung and brain metastases developed and the patient died from the disease 14 months after diagnosis. This is the first case of sarcoma with CIC-DUX4 gene fusion reported in a patient with NF1. Whether this association is coincidental or CIC-DUX4 sarcomas could be related to NF1 remains to be clarified. Study of alternative molecular alterations in EWSR1-negative undifferentiated small round cell sarcomas is clinically relevant, since CIC-DUX4 sarcomas seem to be a very aggressive subset with poor response to the presently used therapeutic regimens.