Early diagnosis of basal cell carcinoma-a cutaneous neoplasia with high incidence-can bring great benefits to the patient. Often, slightly pigmented lesions, small initial lesions, and superficial lesions can represent a clinical and dermoscopic diagnostic challenge for not having the typical findings of this neoplasia. In such cases, optical coherence tomography-a promising technology in dermatology-is an auxiliary, non-invasive resource that can be incorporated into the clinical practice.

Keywords: BASAL CELL CARCINOMA, DIAGNOSTIC IMAGING, OPTICAL COHERENCE TOMOGRAPHY.

Tumoral melanosis is a histological term used to refer to a nodular accumulation of melanophages in the dermis, which clinically arises as a pigmented lesion. It is usually associated with the regression of melanomas or of other melanocytic lesions. The authors present the case of a 45-year old man/woman with a pigmented macule on his/her left leg. The lesion was completely excised and diagnosed as a tumoral melanosis.

Keywords: MELANOMA; SKIN NEOPLASMS; DERMATOSCOPY

Scabies is a contagious cutaneous infection, caused by burrowing of the mite Sarcoptes scabiei var. hominis in the epidermis. The clinical suspicion is due to the history, clinical distribution of lesions and its aspect; however, the confirmation is with the detection of the parasite. We present the features of the diagnostic methods for scabies, from its detection through direct microscopy of skin scrapings from a lesion or with the use of an adhesive tape on the lesions, to its detection using the dermatoscope, a tool available in most dermatology clinics, which, even in unexperienced hands, has acceptable sensitivity and specificity.

Keywords: Dermoscopy; Diagnostic imaging; Microscopy; Scabies; Skin and connective tissue diseases; Skin diseases;

INTRODUCTION: Basal cell carcinoma (BCC) is the most common malign neoplasm. It corresponds to 70-80% of skin tumors. The diagnosis is made based on clinical suspicion combined with dermoscopy, which also allows defining its limits.
OBJECTIVE: To assess whether clinical and dermoscopic criteria are sufficient for the diagnosis and treatment of primary and well-defined BCC.
MATERIALS AND METHODS: Review of suspected cases of well-defined primary BCC surgically approached by excisional biopsy (3 mm margin) at the Dermatology Service of the University of Mogi das Cruzes (2017 to 2019). The Chi-square test was applied to assess the significance of the margins.
RESULTS: 169 injuries were assessed, with a predominance of women in the 8th decade. The histopathological examination concluded on 141 BCCs. When evaluating the excision margins for BCC cases, there was 95% of free margins (p = 0.0004998).
DISCUSSION: There are common dermoscopic elements between BCC and other neoplasms and benign lesions, which justifies other diagnoses found. The 3 mm surgical margin was accurate for well-defined primary BCCs, speeding up healing time and reduces costs.
CONCLUSION: For clinical-dermatoscopic suspicions of well-defined BCC, an excisional biopsy was effective in the diagnosis and clinical safety margins.

Keywords: Dermatoscopy; Diagnosis; Free margins

Diagnosing basal cell carcinomas, both clinically and dermoscopically, is part of most dermatologists' daily routine. However, tumors of this lineage, when densely pigmented, can be a challenge for the physician and surgeon. Dermoscopic features typical of melanocytic lesions may be present in these carcinomas, and the similarity with melanoma results in a real dilemma. More in-depth knowledge on this topic can make a difference in the management of these cases.

Keywords: Carcinoma, Basal cell; Dermoscopia; Diagnosis; Melanoma

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

Riziform bodies are structures in the synovial fluid or attached to the synovium, which macroscopically resemble rice grains. They are common in patients with rheumatoid arthritis and result from a chronic inflammation. They are found in 25% of aspiration procedures or joint surgery. However, there are still no publications reporting its presence in the subcutaneous tissue. We report for the first time the occurrence of riziform bodies in the subcutaneous plane of the palmar region in a patient with rheumatoid arthritis, confirmed by sonographic and anatomopathological examination, successfully treated with surgical drainage, without recurrences after two years of follow-up.

Keywords: Abscess; Rheumatoid arthritis; Dermatopathies; Hand dermatoses; Outpatient Surgical Procedures; Surgical Diagnostic Techniques

The preservation of the surgical margins marking is essential during Mohs micrographic surgery. However, skin degermation during antisepsis and the use of gauze during local anesthesia often remove these markings. The use of the protective film Cavilon^® 3M to fix the marking pen ink was effective in preserving the surgical map, allowing an accurate removal of the surgical specimen.

Keywords: Mohs surgery; Carcinoma, Basal cell; Carcinoma, Squamous cell; Excision Margins