Case Reports in Pathology

Medulloblastoma is an embryonal neuroepithelial tumor that affects mainly childhood and more rarely adults. Medulloblastoma occurring as multiple nodules at diagnosis is a rare and tricky presentation. Here, we describe the case of a previously healthy 47-year-old woman with multiple posterior fossa cerebellar tumors. Histological, immunohistochemical, and molecular analyses were performed to best characterize the two excised lesions. The histopathological analysis revealed different variants of medulloblastoma in the excised nodules, one being extensive nodularity, rare in adults, and the other desmoplastic/nodular with areas of anaplasia. Immunostains and molecular analysis classified both nodules as SHH medulloblastoma. Adult medulloblastoma is extremely rare. Important differences exist between adult medulloblastoma and medulloblastoma arising in children and infants. Such differences are in location, distribution of histological variants and of molecular subgroups, survival rates, and therapeutic options. An extensive morphological and molecular characterization of such rare tumors is necessary to choice the best-tailored therapy.

Burkitt lymphoma (BL) is a highly aggressive but potentially curable disease as long as adequately treated within due time. BL may occur primarily and exclusively in the bone marrow as a form of peripheral and extranodal disease. BL cases with isolated bone marrow involvement are challenging in regard to a prompt diagnostic process. We report a case of a sporadic extranodal subtype of isolated bone marrow BL in an 11-year-old boy. Bone marrow aspiration and biopsy, flow cytometry, and immunohistochemistry along with cytogenetics are compulsory in order to achieve the adequate diagnosis.

This report documents a rare case of an extracranial meningioma on the posterior scalp without apparent dural connection. Additionally, a sebaceous steatocystoma of the anterior scalp presented alongside the meningioma. A steatocystoma localized to the scalp is also remarkably rare. To our knowledge, this is the first report documenting both an extracranial meningioma and a steatocystoma presenting concurrently on the scalp. A male patient in his thirties presented with a mass lesion on the scalp. A CT scan revealed one posterior scalp mass with no intracranial abnormalities. Post excision histologic examination confirmed an extracranial meningioma (meningothelial variant, WHO Grade I). A second anterior scalp mass, not revealed by CT scan, was discovered during surgery. It was excised and diagnosed as a steatocystoma. Meningiomas predominantly occur intracranially but, in some instances, may present as a standalone extracranial tumor without intracranial abnormalities. Because extracranial meningioma is uncommon, it may be overlooked during clinical diagnosis of scalp masses. We recommend that this neoplasm be routinely considered in the differential diagnosis of extracranial tumors. The discovery of another rare tumor—a steatocystoma located in immediate proximity on the scalp—is further remarkable. We briefly review relevant case reports and etiologies and consider a potential relationship between the two neoplasms. However, it remains more likely that the concurrence of these tumors in our patient was simply coincidental.

Metaplastic breast carcinoma is a rare and aggressive condition, accounting less than 1% of breast malignancies. It presents with large mass and frequently with distant metastasis at time of diagnosis. Morphologically, it is characterized by the differentiation of neoplastic epithelium into epithelial or mesenchymal-looking elements like squamous cells, spindle cells, cartilage, or bone and has poor prognosis with its triple negative status.

Angiodysplasia is a common type of lesion characterized by malformed submucosal and mucosal blood vessels. Angiodysplasia of the gallbladder is extremely rare, usually an incidental finding, with only two cases reported. Laparoscopic cholecystectomy is a curative treatment for angiodysplasia of the gallbladder. Our report describes a case of angiodysplasia of the gallbladder in a patient who underwent elective laparoscopic cholecystectomy for biliary colic because of gallstones, and a systematic literature review. We surmise that angiodysplasia of the gallbladder could be a risk factor for gallstones in younger female patients.

A 77-year-old woman with a rare oral intraductal papilloma arising from the minor salivary gland located on the floor of the mouth and causing the mucus retention is reported. Microscopically, the lesion was characterized by unicystic cavity exhibiting the lumen partially filled by papillary projections of the ductal epithelium with varying degree of oncocytic metaplasia. Based on the histopathological analysis, the differential diagnosis of oral intraductal papillomas and other ductal neoplasms of salivary origin are discussed.