RESUMO
Small cell melanoma is a recognized rare variant of malignant melanoma. We report a case of a brown, ulcerated papule on the left third finger of an 80-year-old woman. Microscopic examination revealed the presence within the epidermis of diffuse sheets of monomorphic small to medium-sized cells. The nuclei were round or oval, and hyperchromatic with inconspicuous nucleoli. Melanin pigment was either absent or minimal. This case report draws attention to the difficulties encountered in the histological diagnosis of this rare variant of malignant melanoma.
Assuntos
Melanoma Amelanótico/patologia , Neoplasias Cutâneas/patologia , Idoso , Amputação Cirúrgica , Antígenos de Neoplasias/análise , Biomarcadores Tumorais , Feminino , Dedos/patologia , Dedos/cirurgia , Humanos , Metástase Linfática , Antígeno MART-1 , Melanoma Amelanótico/química , Melanoma Amelanótico/classificação , Melanoma Amelanótico/diagnóstico , Melanoma Amelanótico/secundário , Melanoma Amelanótico/cirurgia , Antígenos Específicos de Melanoma , Proteínas de Neoplasias/análise , Neoplasias Cutâneas/química , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgiaRESUMO
The two major variants of amelanotic malignant melanoma are the verrucous and the polypoid forms. A further--albeit rare--red eczematous variety has also been described. We report two female patients with reddish, non-pigmented, scaly lesions on the upper arm and the shoulder that had developed 2 to 3 years previously. One biopsy showed the diagnosis of a melanoma growing in situ while the second revealed a highly atypical melanocytic tumour. However, the histopathological examination of the entire tumour showed a superficial spreading amelanotic malignant melanoma. Therefore, in non-healing erythematous lesions, even without pigmentation or ulceration, the rare differential diagnosis of amelanotic malignant melanoma should be taken in consideration and a biopsy should be performed prior to therapy without histological control.
Assuntos
Melanoma Amelanótico/classificação , Melanoma Amelanótico/patologia , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/patologia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Melanoma Amelanótico/terapia , Pessoa de Meia-Idade , Doenças Raras/patologia , Doenças Raras/terapia , Neoplasias Cutâneas/terapiaRESUMO
The presence or absence of melanoma cells in human peripheral blood has recently been shown to be associated with disease prognosis, including overall survival. The detection of tyrosinase mRNA-positive circulating melanoma cells by reverse transcription-polymerase chain reaction (RT-PCR) has been limited to disseminated tumours expressing measurable amounts of this melanocyte-specific enzyme. To biologically classify both melanotic and amelanotic melanomas and to evaluate the clinical and prognostic relevance of tumour cell microcontamination, we examined autologous peripheral blood stem cell (PBSC) harvests from patients with advanced malignant melanoma prior to dose-escalated chemotherapy. To assay heterogeneous melanoma cell antigen expression, we developed a highly sensitive RT-PCR using four melanoma- and one tumour-associated antigen as molecular markers. Expression of the melanocyte-associated transcripts of tyrosinase, MART1/Melan-A, tyrosinase-related protein-1 (TRP-1) and tyrosinase-related protein-2 (TRP-2) as well as the tumour-specific transcript of MAGE-3 was analysed by RT-PCR in PBSC harvests from 31 patients. Seven of the 31 PBSC harvests tested positive for one or more molecular markers: two patients for tyrosinase only, and one patient for MAGE-3 only, one patient for tyrosinase and MAGE-3, one for tyrosinase and MART1/Melan-A, and two patients for tyrosinase, MART1/Melan-A, TRP-2 and MAGE-3. mRNA-positive patients exhibited a significantly impaired overall survival (P = 0.0032), with a median survival of 3 months as opposed to 10 months in PBSC mRNA-negative patients. In conclusion, the use of this multiple-marker microcontamination assay allowed for molecular and prognostic classification of advanced malignant melanoma.
Assuntos
Antígenos de Neoplasias , Biomarcadores Tumorais/análise , Células-Tronco Hematopoéticas/química , Melanoma Amelanótico/classificação , Melanoma/classificação , Células Neoplásicas Circulantes/classificação , Adulto , Feminino , Humanos , Imuno-Histoquímica , Interferon Tipo I/genética , Oxirredutases Intramoleculares/genética , Antígeno MART-1 , Masculino , Melanoma/sangue , Melanoma/diagnóstico , Melanoma Amelanótico/sangue , Melanoma Amelanótico/diagnóstico , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Células Neoplásicas Circulantes/química , Proteínas da Gravidez/genética , Prognóstico , RNA Mensageiro/análise , RNA Neoplásico/análise , Sensibilidade e Especificidade , Células Tumorais CultivadasRESUMO
Objetivo: comunicar una forma rara de melanoma maligno amelanótico, denominada eczematoide o tipo placa inflamatoria. Caso clínico: paciente de sexo femenino y 74 años de edad, que presenta una placa eczematoide en pierna, con diagnóstico histopatológico de melanoma extensivo superficial, nivel Clark IV e índice de Breslow 1,7 mm. Conclusión: recordar la existencia de melanomas "falsos negativos" o "evasores de campaña", que no cumplen con el ABCD clásico de los melanomas (AU)
Assuntos
Humanos , Feminino , Idoso , Melanoma Amelanótico/diagnóstico , Eczema/complicações , Melanoma Amelanótico/classificação , Melanoma Amelanótico/patologia , Neoplasias Cutâneas/cirurgiaRESUMO
Objetivo: comunicar una forma rara de melanoma maligno amelanótico, denominada eczematoide o tipo placa inflamatoria. Caso clínico: paciente de sexo femenino y 74 años de edad, que presenta una placa eczematoide en pierna, con diagnóstico histopatológico de melanoma extensivo superficial, nivel Clark IV e índice de Breslow 1,7 mm. Conclusión: recordar la existencia de melanomas "falsos negativos" o "evasores de campaña", que no cumplen con el ABCD clásico de los melanomas
