Intestinal adenosquamous carcinoma with a synchronous skin metastasis: a immunohistochemical and molecular analysis.

INTRODUCTION: Intestinal adenosquamous carcinoma (ASC) is a rare colorectal neoplasm frequently occurring at onset as a locally advanced disease with distant metastases. The liver is the most common site of metastasis, followed by the peritoneum and the lung. Cutaneous metastases from usual colorectal adenocarcinoma occur in about 3% of cases, both at the time of diagnosis in advanced disease and during the follow-up. To the best of our knowledge, skin metastasis from ASC has never been described, and no biological landscape of ASC has ever been investigated. METHODS: We report a case of synchronous intestinal ASC and cutaneous single facial metastasis in a 70-year-old man with morphological, immunohistochemical, and molecular analysis of primary and metastatic lesions. RESULTS: Primary and metastatic ASC showed the same morphological and immunohistochemical features. Target sequencing analysis revealed, both in primary tumor and metastasis, a pathogenic KRAS gene missense mutation c.38G > A p.(Gly13Asp) and a likely pathogenic CTNNB1 gene missense mutation c.94G > A p.(Asp32Asn). A nuclear localization of ß-catenin protein in adenocarcinomatous component of primary and metastatic lesions was observed on immunohistochemistry. CONCLUSION: We describe a case of single synchronous facial cutaneous metastasis from intestinal ASC showing KRAS and CTNN1B mutations both on primary and metastatic lesions.

Clinicopathologic Features of Hydroa Vacciniforme-Like Lymphoma: A Series of 9 Patients.

Hydroa vacciniforme-like lymphoma is a recently recognized cutaneous T-cell lymphoma associated with Epstein-Barr virus. The disease is observed in children of Latin American or Asian ethnicity. The authors report the clinical, histopathological, and immunophenotypical features of 9 new Mexican patients (M:F = 2:1; mean age, 14.5 years; median age, 13.3 years; age range, 4-27 years), expanding on previous observations of this elusive disease. The most common clinical aspects were persistent facial edema with necroses and pitted scars. Histopathological analyses revealed variably dense lymphoid infiltrates with common angiodestructive features. Neoplastic cells expressed CD3 and cytotoxic markers in all cases and were constantly positive for Epstein-Barr virus (EBER-1). Expression of other markers was variable. Follow-up data revealed that all patients died within 6 months or less, thus showing a very aggressive course with poor prognosis.

Pan-cytokeratin markers for rapid frozen section immunocytochemistry from head and facial Mohs cases of basal cell carcinoma: a comparison and evaluation to determine the marker of choice.

The application of immunocytochemistry in the field of Mohs micrographic surgery (MMS) is well established. This study evaluates the use of pan-cytokeratins (AE1/AE3, MNF116 and AE1/AE3+PCK26) in the assessment of basal cell carcinoma (BCC) on frozen tissue debulk specimens. Fifty-five cases of BCC, all from head and facial sites, were assessed in the study. In addition to staining all cases for the three cytokeratin antibodies under investigation, sections were also stained with haematoxylin and eosin (H&E) to demonstrate tumour architecture and morphology. All sections for immunocytochemistry were stained on a Roche Ventana BenchMark Ultra automated platform employing a rapid frozen section protocol. Results were assessed based on the intensity of staining of keratinocytes (scale: 0-100%), as well as sensitivity of staining determined by the total percentage of keratinocytes stained within the tissue section. AE1/AE3 demonstrated the most consistent staining both in terms of intensity of staining and sensitivity, with a mean of 99.1% and 99.9%, respectively. AE1/AE3+PCK26 average results indicated scores of 70.6% for intensity and 87.2% for sensitivity, with MNF116 scoring 92.9% for intensity but only 57.3% for sensitivity. The data indicate that AE1/AE3 is the best pan-cytokeratin antibody to use in the assessment of BCC in MMS. The use of cytokeratin immunocytochemistry is justified in morphologically complex cases of BCC, or in cases where dense inflammatory infiltrate surrounding any suspicious cells make identification of small numbers of tumour cells difficult to determine with just an H&E stain. The significant rationale is that cytokeratin staining is a valuable adjunct in the study of tumour cell assessment in cases of MMS for BCC. In addition, the use of anti-AE1/AE3 cytokeratin antibodies provides the most consistent staining results for such cases.

[Cutaneous chondroid syringoma]. / Syringome chondroïde cutané.

INTRODUCTION: Chondroid syringoma (CS) is a rare cutaneous tumor characterized by mixte epithelial and mesenchymal component. The confident histological diagnosis can be obtained by immuno-histochemistry study. Here we present 10 new cases with their clinico-hystological characteristics. METHODS: The 10 cases were observed between January 2000 and august 2013, in Fort-de-France and Louis-Mourier universitary hospitals. For all the cases a controlled histological study was performed by a dermatopathologist expert and immuno-histochemistry was added. Clinical and immuno-histological data were analyzed. RESULTS: The lesions were almost localized on the face (3/10) and the extremities (3/10). The size was about 1.2 to 5.2cm. Every case was treated by surgery, no malignant case was diagnosed. Histologically, all the 10 cases presented as a well-limited dermic tumor with a mixte epithelial and mesenchymal component. The stroma was myxo-chondroid, and the epithelial component consisted in epithelial cavities lined by one or two cell layers with eccrine (4/10) or apocrine (5/10) features. Immuno-chemistry study reveals positivity for EMA, ACE and CK7 for the internal cells, and positivity for S100 protein and vimentin of the extern cell layer. DISCUSSION: Chondroid syringoma is characterized by a mixte epithelial with eccrine and apocrine cells and a myxo-chondroid stroma. Our study has some clinical and histological particularities (lesions on the extremities, epidermic connecting…). The main differentials diagnoses are the other annexial tumors. The treatment is surgical. CONCLUSION: The histological diagnosis of CS is quite easy, but in case of doubt, immuno-chemistry will help, showing a double mesenchymal and epithelial differentiation.

Spindle Cell Atypical Fibroxanthoma: Myofibroblastic Differentiation Represents a Diagnostic Pitfall in This Variant of AFX.

Atypical fibroxanthoma (AFX) is a low-grade, dermal, mesenchymal neoplasm, which lacks a specific lineage of differentiation. The classical histologic appearance of AFX is that of a pleomorphic and spindle cell neoplasm with marked nuclear pleomorphism, mitotic figures, and often prominent storiform pattern that superficially resembles a pleomorphic high-grade sarcoma ("malignant fibrous histiocytoma"). Many histologic variants have been described. We have reviewed 15 cases of AFX characterized by a pure spindle cell morphology that could be easily mistaken for other spindle cell dermal neoplasms. All of our cases were stained with CD68, CD163, CD10, S-100p, p63, wide-spectrum keratin, CD31, CD34, smooth muscle actin (SMA), desmin, calponin, and h-caldesmon. All 15 cases showed an immunoprofile consistent with AFX. In 9 cases, SMA was also strongly expressed; this finding, coupled with the malignant spindle cell histomorphology, can lead to an erroneous diagnosis of cutaneous leiomyosarcoma with potential clinical consequences. Awareness of this pattern of immunoreactivity in this unusual variant of AFX is of importance for avoiding diagnostic misinterpretation. This study intends to characterize the nature and frequency of SMA immunoreactivity in AFX and to discuss the potential diagnostic pitfalls of immunohistochemical markers in distinguishing this entity from other malignant spindle cell neoplasms.

Anatomoclinical study of 30 cases of sclerosing sweat duct carcinomas (microcystic adnexal carcinoma, syringomatous carcinoma and squamoid eccrine ductal carcinoma).

BACKGROUND: Microcystic adnexal carcinoma (MAC), syringomatous carcinoma (SC) and "Squamoid eccrine ductal carcinoma" (SEDC) are rare sclerosing adnexal tumours. OBJECTIVE: To understand the histogenesis of these tumours and possible clinical implications. METHODS: We conducted a retrospective study of 30 cases, 18 MAC, 5 SC and 7 SEDC reviewed and classified by a panel of dermatopathology experts, with immunohistochemical analysis of keratins, including K77, a new keratin specific of eccrine ducts, and PHLDA1 expressed in adnexal structures. RESULTS: There was a strong female predominance, with only five cases occurring in men. Patients with MAC and SC were younger (mean age 56 and 47 years) than those with SEDC (mean age 81 years). The most common localization was the cheek in SC and SEDC and the periocular area in MAC. Two cases of SEDC were found in organ transplant patients. No recurrence or metastases were observed after complete surgery of MAC, or SC (mean follow-up 7.2 years and 4.7 years), whereas one case of SEDC recurred and another could not be fully excised. MAC and SC had similar histological features, except for cysts. In MAC, calcifications, granulomas, connection to follicles, keratin expression pattern, PHLDA1 positivity and K77 negativity indicated a follicular histogenesis, whereas in SC, K77 positivity and keratin expression pattern were consistent with a differentiation towards eccrine apparatus. SEDC was composed of strands centred by ducts and nests with squamous differentiation and displayed K77 ductal positivity in all cases, a finding consistent with an eccrine origin. CONCLUSION: Our study demonstrated that MAC and SC have similar clinical characteristics, although histogenesis differs and show arguments for the individualization of SEDC.

Cutaneous Pleomorphic Rhabdomyosarcoma Occurring on Sun-Damaged Skin: A Case Report.

Rhabdomyosarcoma (RMS) is a malignant soft tissue tumor with skeletal muscle differentiation that can rarely present as a primary cutaneous tumor. There are 3 main subtypes of RMS: embryonal, alveolar, and pleomorphic. Primary cutaneous pleomorphic RMS is extremely rare, there being only 9 reported cases in the literature, 2 of which are radiation induced. We present a case of primary pleomorphic RMS occurring on the sun-damaged skin of the face of an 89-year-old woman. The tumor was diagnosed by histology, immunohistochemistry, and electron microscopy. The patient was treated by surgery and adjuvant radiotherapy. The tumor recurred rapidly after surgical excision. She died 2 months after the diagnosis from complications of treatment, local symptoms of tumor, and concurrent illnesses. Primary cutaneous pleomorphic RMS is a rare tumor of adults and pursues an aggressive clinical course.

Immunohistochemical profile of oral mucosal and head and neck cutaneous melanoma.

BACKGROUND: In addition to ultraviolet radiation exposure, various molecular markers may differ between oral mucosal and cutaneous head and neck melanomas and lead to variations in their biologic behavior and prognosis. The aim of this study was to compare four such markers, namely microphthalmia transcription factor (MITF), P75, P53, and Ki-67 in malignant melanomas originating from the oral cavity and head and neck skin. METHODS: A total of 19 oral mucosal and 23 head and neck cutaneous melanomas were subjected to immunohistochemical analysis using antibodies against MITF, P75, P53, and Ki-67. Statistical comparison of data was performed by t-test and chi-square analysis (P < 0.05). RESULTS: Significant differences in MITF (P = 0.016) and Ki-67 (P = 0.002) were observed between oral mucosal and cutaneous melanomas. P75 (P = 0.80) and P53 (P = 0.76) did not differ significantly, between these locations. CONCLUSIONS: According to the results obtained in this study, the biological properties of cutaneous and mucosal melanoma differ, especially regarding MITF and Ki-67.

Acral Mycosis Fungoides With Epidermal Microvesiculation Mucinosis.

Mycosis fungoides (MF) is the most common type of primary cutaneous T-cell lymphoma. This entity may present with a wide spectrum of clinicopathological manifestations and mimic different dermatoses. Among its histopathological variants, spongiosis is an infrequent finding, and spongiotic microvesiculation is particularly rare. Mucinous deposition is a common event in folliculosebaceous units of folliculotropic MF but rarely described within the epidermis. Herein, we report a patient with eczematous palmoplantar lesions whereby the histological, immunohistochemical, and molecular studies confirmed to be a unique case of MF showing epidermal microvesiculation mucinosis.

Papillary haemangioma: a case report of multiple facial location.

Papillary haemangiomas were recently defined as morphologically distinct and benign cutaneous haemangiomas showing a predominantly intravascular capillary proliferation within dilated thin-walled dermal blood vessels. We describe the case of a 45-year-old woman who presented with multiple eruptive red-bluish raised papules and nodules distributed over the skin of the chin that were related to a papillary haemangioma.