Résumé
Mazabraud syndrome (MS) is a rare and sporadic disorder. It is mainly characterized by fibrous dysplasia (FD) of single or multiple bones and intramuscular myxomas (IM). Data on the prevalence since it was first reported, clinical features, and prognosis are extremely scarce. We report a case of a 59-year-old woman with IM and polyostotic FD. She also had multiple cafe’-au-lait spots suggestive of McCune-Albright syndrome (MAS). On magnetic resonance imaging, there are masses with well-defined heterogeneous enhancement, accompanied by an inner cyst in the vastus lateralis muscle and femur. These radiological results are identical to those of FD. After surgical intervention with excision of intramuscular soft-tissue mass, a diagnosis of IM of MS was confirmed. Given that cafe’-au-lait spots also appeared, the patient was diagnosed with a variant of MS with some of the clinical characteristics of MAS.
Résumé
Sebaceous neoplasms are rare adnexal tumors that can present a challenge to clinicians. Only four cases of sebaceous carcinoma with sebaceoma have been reported in the literature. Herein, we describe the case of a sebaceous carcinoma originating from a sebaceoma in a solitary nodule of the posterior neck. Immunohistochemically, the tumor cells were strongly positive for epithelial membrane antigen and p53. It is possible that adnexal carcinomas may arise from malignant transformation of their benign counterparts as well as de novo. Malignant transformation was likely in this case because the lesion was composed of distinct benign and malignant components, and the benign component showed the typical histopathological features of sebaceoma. This case underscores the fact that partial and superficial biopsies sometimes may not provide the correct diagnosis. If a surgeon suspects malignancy based on a clinical examination, then it is mandatory to perform a deep biopsy.
Résumé
Sebaceous neoplasms are rare adnexal tumors that can present a challenge to clinicians. Only four cases of sebaceous carcinoma with sebaceoma have been reported in the literature. Herein, we describe the case of a sebaceous carcinoma originating from a sebaceoma in a solitary nodule of the posterior neck. Immunohistochemically, the tumor cells were strongly positive for epithelial membrane antigen and p53. It is possible that adnexal carcinomas may arise from malignant transformation of their benign counterparts as well as de novo. Malignant transformation was likely in this case because the lesion was composed of distinct benign and malignant components, and the benign component showed the typical histopathological features of sebaceoma. This case underscores the fact that partial and superficial biopsies sometimes may not provide the correct diagnosis. If a surgeon suspects malignancy based on a clinical examination, then it is mandatory to perform a deep biopsy.