RESUMO
Rarely, Rosai-Dorfman disease (RDD) manifests exclusively in the skin, typically as nodules on the trunk and extremities. Recognition of characteristic histopathologic features enables diagnosis of RDD. A 55-year-old female presented with a 7-year history of cutaneous nodules involving the trunk and extremities. A prior skin biopsy specimen at a different institution had demonstrated a dense dermal lymphohistiocytic infiltrate with histiocytes containing GMS+ forms, favored to represent cryptococcal organisms, with a differential diagnosis including other infections with parasitized histiocytes. Despite antibiotic therapy, lesions persisted. After a presentation to our institution, a biopsy specimen showed a diffuse infiltrate, including histiocytes with voluminous pale cytoplasm with focal emperipolesis of inflammatory cells and S100 immunohistochemical positivity. Clinical and radiologic examinations did not identify significant extracutaneous involvement. A genetic study performed on the biopsy specimen identified a K57Q mutation of MAP2K1. The presence of this mutation correlated with prior reports of MAP2K1 mutation in classic RDD, thereby supporting our histopathologic diagnosis of RDD over an infectious process and further illuminating options for targeted therapies. At 3-year follow-up, the patient has been managed with a course of systemic corticosteroids and excision of bothersome lesions. Consideration of systemic therapy is ongoing.
RESUMO
Non-Down-syndrome-related acute megakaryoblastic leukemia (non-DS-AMKL) is a rare form of leukemia that can present with a variety of initial symptoms, including fever, rash, bruising, bleeding, or other more clinically challenging symptoms. Herein, we describe a 19-month-old female patient who presented with left lower extremity pain and language regression who was diagnosed with AMKL, not otherwise specified (NOS), on the basis of peripheral blood and bone marrow analysis, as well as cytogenetic and molecular diagnostic phenotyping. Of note, in addition to this patient's karyotype showing trisomy 3, a fusion between CBFA2T3 (core-binding factor, alpha subunit 2, translocated to, 3) on chromosome 16 and GLIS2 (GLIS family zinc finger protein 2), also on chromosome 16, was observed. Patients with AMKL who have trisomy 3 with CBFA2T3::GLIS2 fusions are rare, and it is not known if the co-occurrence of these abnormalities is coincidental or biologically related. This highlights the continued need for further expansion of genetic testing in individuals with rare disease to establish the groundwork for identifying additional commonalities that could potentially be used to identify therapeutic targets or improve prognostication.
Assuntos
Leucemia Megacarioblástica Aguda , Criança , Feminino , Humanos , Lactente , Cariótipo , Leucemia Megacarioblástica Aguda/diagnóstico , Leucemia Megacarioblástica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Repressoras/genética , Trissomia/genéticaRESUMO
This case report describes a unique pattern of human epidermal growth factor receptor 2 expression in a patient with uterine carcinosarcoma. The endometrial tumor showed biphasic morphology composed of serous carcinoma and a heterologous high-grade sarcoma component. Human epidermal growth factor receptor 2 immunostaining showed positive (3+) expression in foci of myoinvasion, lymphovascular invasion, and lymph node metastasis but was negative in both the endometrial surface tumor and sarcomatous component. Fluorescent in situ hybridization testing for human epidermal growth factor receptor 2 confirmed no amplification within the endometrial surface carcinoma component and amplification of the lymphovascular invasion component. As the use of human epidermal growth factor receptor 2 immunohistochemical evaluation becomes more commonplace for therapeutic consideration in patients with uterine carcinosarcoma, interpretation of the immunohistochemical should be performed preferentially on large tissue sections including both a surface, myoinvasive portions, and suspected areas of lymphovascular invasion and lymph node metastasis.