Merkel cell carcinomas are highly aggressive neuroendocrine skin tumors that have a poor prognosis. The authors present a case report and emphasize the importance of early diagnosis and treatment.

Keywords: CARCINOMA, MERKEL CELL, IMMUNOHISTOCHEMISTRY, SKIN

Introduction: Skin cancer is the most common type of neoplasia in humans, with ultraviolet radiation being considered the main cause. Basal cell carcinoma is the most frequent cutaneous neoplasia, and photoprotection is seen as the most effective measure in its prevention. Nonetheless, there is still some resistance to the use of sunscreens among the general population. There is also a lack of reports in the literature on whether such resistance differs in patients with basal cell carcinoma. Objectives: To evaluate whether there is change in habits regarding exposure to the sun and use of sunscreen after diagnosis of basal cell carcinoma in patients treated at the Dermatology Outpatient Clinic of Universidade Federal de Ciências da Saúde de Porto Alegre (RS), Brazil. Methods: A cross-sectional study was carried out with 120 patients diagnosed and treated for basal cell carcinoma, who responded to a questionnaire regarding their sun exposure habits and use of photoprotection methods before and after diagnosis. Results: Of the 120 patients interviewed, 73.3% reported changes in their habits regarding exposure to the sun and use of sunscreen after receiving a diagnosis of basal cell carcinoma. The main reasons alleged by those who denied having changed their behavior towards sun exposure (26.7%), were the lack of fear of new tumors, as well as the high cost of sunscreens. Conclusions: A diagnosis of basal cell carcinoma motivates most patients to improve their use of preventive measures regarding protection from the sun. Nonetheless, about a third of the studied population still resisted such measures, the main reason cited being the high cost of sunscreens. Therefore, awareness campaigns about the importance of using photoprotection methods to prevent skin cancer must be implemented, and the development of programs aimed at making sunscreens available to the general population – especially to high-risk patients – must be sought.

Keywords: SKIN NEOPLASMS, CARCINOMA, BASAL CELL, HEALTH EDUCATION

Eccrine spiradenoma is a rare benign adnexal epithelial neoplasm characterized by a bluish-pink, slow-growing solitary nodule, coursing with paroxysmal pain, mainly in young adults. It is most commonly located in the trunk and extremities. Bleeding and/or ulceration are common in the giant vascular variant, which is characterized by a size greater than 2 cm in diameter and a high degree of vascularization seen on histology. Its clinical characteristics are unspecific and require biopsy with histological analysis for diagnosis. Its histology presents one or more basophilic intradermal lobules enveloped in a fibrous capsule without connection to the epidermis. It presents two types of cells: small cells with dark nuclei in the periphery and large cells with light nuclei in the center. An accurate diagnosis is important due to the fact that it can develop into a potentially fatal malignancy - which is a rare phenomenon and occurs most often in the multiple variant. A rare case of eccrine spiradenoma in the abdomen with bleeding associated is described in the present paper, as well as a discussion on possible treatments.

Keywords: ECCRINE SPIROADENOMA, BENIGN EPITHELIAL NEOPLASIA, SEBACEOUS GLANDS

Basal cell carcinoma is the most common type of cancer and its non-surgical treatment has been the subject of many studies. Large lesions of this tumor are therapeutic challenges and the effective topical treatment has good applicability. The authors present a female patient diagnosed with multicentric superficial basal cell carcinoma in the lumbar region for more than 20 years, who refused to be treated surgically. The tumor reached dimensions of 12 cm x 10 cm. A decision was made for a non-surgical therapy, with the application of Imiquimod in a treatment of 5 weekly applications for 2 months. The treatment led to a clinical and histological cure, without recurrence to date (36 months), with excellent aesthetic results and few side effects.

Keywords: CARCINOMA, BASAL CELL; THERAPEUTICS; NEOPLASMS

The Merkel cell carcinoma is a rare and highly aggressive neuroendocrine skin tumor. The purpose of this paper is to warn of the possibility of this diagnosis, usually not considered as an initial hypothesis in cutaneous neoplasias. The authors describe two cases of elderly female patients with complaints of a single erythematous nodule on the face. The diagnoses of basal cell carcinoma and amelanotic melanoma were considered. The presence of telangiectasias was evident at dermoscopy. The incisional biopsy's histology evidenced Merkel cell carcinomas. This neoplasia typically occurs in Caucasian patients with over 65 years of age, emerging as an erythematous-purplish nodule of rapid growth, with immunohistochemistry being essential for the diagnosis.

Keywords: SKIN NEOPLASMS; CARCINOMA, MERKEL CELL; NEUROENDOCRINE TUMORS; IMMUNOHISTOCHEMISTRY

Basal cell carcinoma corresponds to the majority of malignant cutaneous malignancies in Brazil, predominating in middle-aged white individuals, mainly affecting the upper two-thirds of the face and occurring due to several etiological factors. The ideal treatment consists of complete removal with free lesion margins. For better functional and aesthetic results, reconstruction of the surgical wound with flaps or grafts may be necessary. Two types of reconstruction are described in patients with double surgical defects on the face, close to each other: one with a single rotation flap and another with a double rotation flap, also called Yin-Yang.

Keywords: SKIN NEOPLASMS; CARCINOMA, BASAL CELL; SURGICAL FLAPS

The Merkel cell carcinoma is a rare tumor of neuroendocrine and epidermal origin and with poor prognosis. It is classically associated with immunosuppression, exposure to the sunlight and, more recently, with the polyomavirus. It is positive for epithelial and neuroendocrine markers. The combined expression of these markers confirms the diagnosis. Polyomavirus tumors have an unfavorable prognosis. The authors report a case of Merkel cell carcinoma with atypical immunophenotype (CK20 negative) and aggressive behavior. The present report is aimed at highlighting the importance of dermatologists having knowledge of different immunophenotypes that may be associated with the Merkel cell carcinoma.

Keywords: CARCINOMA, MERKEL CELL; IMMUNOHISTOCHEMISTRY; MERKEL CELL POLYOMAVIRUS

Basal cell carcinoma (BCC) is more common in the lower eyelid region when it affects the periorbital region. It occurs predominantly in men between 50-70 years and has a high recurrence rate. Although it rarely metastasizes, orbital invasion can occur. This study aims to present a case of pigmented BCC of unusual location. The location of BCC in the upper eyelid region is rare, and dermoscopy is essential to distinguish it from its primary differential diagnoses.

Keywords: Basal cell carcinoma; Dermoscopy; Eyelid Neoplasms

The recurrent squamous cell carcinoma (SCC) needs an appropriate approach to decrease the risk of recurrences. We report the case of a man diagnosed with SCC on the left temporal region treated by conventional surgery, with infiltration and erythema in the scar area. Reflectance confocal microscopy suggested the diagnosis of recurrent SCC confirmed by histopathology. New surgery and traditional intraoperative frozen section were performed. After two months, the patient had a new relapse, finally treated with Micrographic surgery without new involvement. This article highlights the importance of micrographic surgery in treating SCC, aiming to decrease new recurrences.

Keywords: Skin Neoplasms; Mohs Surgery; Carcinoma, Squamous Cell

O queratoacantoma (QA), apesar de frequente na prática diária, é um tumor que gera questionamentos. O aspecto mais intrigante associa-se à sua posição no limite entre malignidade e benignidade. A abordagem do tumor, bem como sua classificação, é controversa. Na definição da conduta, é importante levar em conta o potencial de transformação para carcinoma espinocelular. Desse modo, a excisão cirúrgica é a terapia de escolha, sempre que possível. Algumas situações merecem atenção adicional, como a imunossupressão associada. Neste artigo, relatamos um caso de QA gigante em um paciente com síndrome da imunodeficiência adquirida tratado com cirurgia micrográfica de Mohs.

Keywords: Ceratoacantoma; Retalhos Cirúrgicos; Neoplasias Nasais; Neoplasias Cutâneas; Cirurgia de Mohs; Síndrome de Imunodeficiência Adquirida; HIV; Imunossupressão

Sarcomas são neoplasias mesenquimais malignas, raras, que acometem, principalmente, crianças e adolescentes. O rabdomiossarcoma, subtipo oriundo da musculatura esquelética, é condição incomum em adultos, acometendo sítios de localização não habitual, crescimento rápido e de difícil tratamento. Apresenta-se caso de adulto jovem com nodulação em lóbulo auricular esquerdo, cuja análise histopatológica e imuno-histoquímica confirmou tratar-se de rabdomiossarcoma alveolar, o qual foi conduzido em conjunto com a Oncologia.

Keywords: Rabdomiossarcoma Alveolar; Miogenina; Desmina; Excisão de Linfonodo

Merkel cell carcinoma is a rare and aggressive neuroendocrine skin tumor usually presenting as a single lesion in the head or neck region. We report a case of atypical topography and presentation, with multiple and simultaneous tumors on the left leg of rapid progression associated with palpable inguinal lymphadenopathy and diagnostic confirmation by histopathology and immunohistochemistry. Exeresis of the left inguinal lymph node and skin lesions with a safety margin was performed.

Keywords: Carcinoma Merkel cell; Merkel cells; Merkel cell polyomavirus

Merkel cell carcinoma is a rare and aggressive cutaneous neuroendocrine cancer that occurs in the photodamaged skin of white and elderly patients, usually presenting as a solitary plaque or nodule in the head and neck region. When located in the lower palpebral area, reconstructing the defect resulting from its excision can become challenging for the dermatological surgeon due to the local cosmetic and functional peculiarity. We report the use of a bilobed flap for lower eyelid reconstruction with a satisfactory result, both in terms of aesthetics and the resulting functionality.

Keywords: Surgical flaps; Eyelids; Carcinoma, Merkel Cell; Case reports

Fibromyxosarcoma is a rare subtype of soft tissue sarcoma characterized by the presence of spindle cells and myxoid matrix. We report the case of an older patient who presented with progressive growth of a nodule in the interscapular region, and further investigation confirmed the diagnosis of high-grade fibromyxosarcoma. Notably, this neoplasm more commonly occurs in the lower limbs and may exhibit recurrence associated with increased histological grade. Therefore, early diagnosis and treatment are crucial for mitigating morbidity and mortality. We emphasize the significance of diagnosing an atypical case and providing timely therapeutic intervention, contributing to the optimization of clinical outcomes.

Keywords: Sarcoma; Neoplasms, Connective and Soft Tissue; Solitary Fibrous Tumors

A narrative review was performed to clarify the ontogenesis of Merkel-cell carcinoma. It is hypothesized that the cells are derived from the embryonic neural crest, skin stem cells, epithelial cells, pre-/pro-B cells, dermal fibroblasts, or metastatic cells from other types of carcinomas. The influence of epigenetics was also considered. Methodologically, to prepare the summary articles were selected from the PubMed and SciELO databases and cited references. The results suggest that it is more likely that Merkel-cell carcinoma has multiple origins, possibly from poorly differentiated cells.

Keywords:

A narrative review was performed to clarify the ontogenesis of Merkel-cell carcinoma. It is hypothesized that the cells are derived from the embryonic neural crest, skin stem cells, epithelial cells, pre-/pro-B cells, dermal fibroblasts, or metastatic