Extranodal Rosai-Dorfman Disease of Breast Mimicker of Breast Malignancy.

Rosai-Dorfman-Destombes (RDD) disease is also known as sinus histiocytosis with massive lymphadenopathy. It is an uncommon heterogeneous disease of children and young adults. Most of the patients with RDD generally present with painless lymphadenopathy, while extranodal and multisystem manifestation of the disease is unusual.

Partial Response to Naxitamab for Brain Metastasis in Neuroblastoma.

Neuroblastoma (NBL) is a common pediatric tumor arising from sympathetic ganglion cells. High-risk NBL is based on age, stage, histology, and MYCN amplification, and is associated with a high mortality rate. The combination of naxitamab (NAX) and granulocyte-macrophage (cerebrospinal fluid) is a new treatment for high-risk and relapsed NBL approved for bone or bone marrow disease.

Merkel Cell Carcinoma of the Left Cheek With Testicular Metastasis: An Uncommon Occurrence.

Merkel cell carcinoma (MCC) is an infrequent and aggressive neuroendocrine tumor of the skin. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is an effective imaging technique with good diagnostic accuracy that may be used to help stage MCC and for detecting unexpected recurrences and distant metastatic disease. Other causes of testicular neoplasms, such as primary testicular tumors, lymphomas, or anaplastic small cell melanomas, are difficult to differentiate from MCC testicular metastases on imaging, and tumor markers and histopathology will help confirm it.