Thymic Neuroblastoma within a Thymic Cyst in an Adult

Anterior mediastinal neuroblastoma in an adult: an additional case of a rare tumor in an unusual location with review of the literature

Neuroblastoma is rare in the adult population, especially in thoracic or mediastinal locations, with only 25 previously reported cases. We report an additional example of primary thymic neuroblastoma in a previously asymptomatic 71-year-old man with an anterior mediastinal mass who underwent robotic excision with pericardium and adjacent lung. The tumor was a 5.2 cm partially encapsulated, white-tan and rubbery mass with grossly identifiable areas of necrosis (25%) and hemorrhage. Histologically, the specimen showed a rim of adipose tissue and residual thymic tissue with areas of cystic thymic epithelium and prominent lymphoid tissue containing Hassall's corpuscles. The tumor was composed of uniform, round cells with scant cytoplasm and small nuclei with inconspicuous nucleoli set within a background of conspicuous neuropil. Mitotic figures were easily found. By immunohistochemistry, the tumor cells expressed synaptophysin, chromogranin, NKX2.2 (diffuse, nuclear), GFAP (patchy), SMI31 (neurofilament) (focal, cytoplasmic), and TdT (diffuse, nuclear), while lacking expression of CD99, TTF-1, CK 20, MCPyV, PHOX2B, Olig2, OCT3/4, CD45, CD3 and PAX5. S100 protein was negative in the neuroblastic cells, with scattered positive cells in a vague sustentacular-like pattern. Fluorescence in situ hybridization for isochromosome 12p and EWSR1 gene rearrangement were negative. As thymic neuroblastoma is extremely rare in adults, a neuroblastic tumor of germ cell origin (either primary or metastatic) or spread from a sinonasal tract tumor should be excluded because of differing treatments and prognoses. The properties of these rare neoplasms appear similar to olfactory neuroblastoma rather than pediatric-type neuroblastoma.

Primary Neuroblastoma of the Thymus

ABSTRACT

Primary neuroblastoma is the most common extracranial solid tumor in children and may occur anywhere along the sympathetic chain, but most commonly occur in abdominal/retroperitoneal region including the adrenal glands, followed by the thorax. In children, the most primary neuroblastomas in the thorax are in the posterior mediastinum. We present herein an extremely rare case of primary neuroblastoma of thymus in pediatric patient.

The Rarest of Rare Thymic Lesions: A 10-Year Surgical Pathology Experience

The thymus is a specialized primary lymphoid organ located in the midline pre-vascular mediastinum. The organ is the site of various pathological processes, neoplastic and not, whose rarity has not allowed in-depth studies on clinical or histological features of rarest and unusual variants. Herein, we report a 10-year Padova experience in the surgical pathology of the thymus, focusing on the pathological description of nonneoplastic lesions and rare epithelial and mesenchymal tumors recorded in our database, which comprises over 600 thymectomies. The extrapolated rare cases have been categorized into four groups that included 15 cysts, 18 carcinomas, 5 neuroendocrine tumors, and 2 soft tissue tumors. The cases are described from a clinical and pathological point of view and discussed in dedicated sections with a review of the most important literature. In this case, review series, we aim to update the epidemiology of these rare entities, improve diagnostic awareness, and finally, promote a collaborative network between referral centers.

Neuroblastoma in early childhood: A rare case report and review of literature

Neuroblastoma is an extremely rare pediatric neoplasm whose prognosis becomes poor and poor as the age advances. It can be sporadic or nonfamilial in origin. It is primarily a tumor of abdominal origin from where it metastasis to lymph nodes, liver, intracranial and orbital sites, and central nervous system. There is no standard dental treatment protocol for the management of neuroblastoma due to its poor survival rate and rarity. However, dental treatment may follow the protocol of preventive and restorative. Surgicals should be performed under supervision as it may trigger metastasis. We report a rare case of neuroblastoma in a 3-year-old child presenting classical oral manifestations such as bilateral palatal swelling, rolled border ulcer on the posterior part of hard palate adjacent to primary molars, and bilateral proptosis.

The 2015 World Health Organization Classification of Tumors of the Thymus: Continuity and Changes

This overview of the 4th edition of the World Health Organization (WHO) Classification of thymic tumors has two aims. First, to comprehensively list the established and new tumor entities and variants that are described in the new WHO Classification of thymic epithelial tumors, germ cell tumors, lymphomas, dendritic cell and myeloid neoplasms, and soft-tissue tumors of the thymus and mediastinum; second, to highlight major differences in the new WHO Classification that result from the progress that has been made since the 3rd edition in 2004 at immunohistochemical, genetic and conceptual levels. Refined diagnostic criteria for type A, AB, B1-B3 thymomas and thymic squamous cell carcinoma are given, and it is hoped that these criteria will improve the reproducibility of the classification and its clinical relevance. The clinical perspective of the classification has been strengthened by involving experts from radiology, thoracic surgery, and oncology; by incorporating state-of-the-art positron emission tomography/computed tomography images; and by depicting prototypic cytological specimens. This makes the thymus section of the new WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart a valuable tool for pathologists, cytologists, and clinicians alike. The impact of the new WHO Classification on therapeutic decisions is exemplified in this overview for thymic epithelial tumors and mediastinal lymphomas, and future perspectives and challenges are discussed.

Ataxia induced by a thymic neuroblastoma in the elderly patient

Thymic neuroblastoma is a rare tumor with only few reports in modern literature. Whereas most data is taken from childhood neuroblastoma, little is known about the characteristics of the disease in the adult and elderly population.

There are significant differences between adult and childhood neuroblastoma which are reviewed below.

We report a case of a 62-year-old male who presented with neurological symptoms of ataxia and opsoclonus and an anterior mediastinal mass. Ultimately, the patient underwent a resection of the mass and pathologic review identified a thymic neuroblastoma. This is the first case of thymic neuroblastoma associated with symptomatic central nervous system disease; it is presented with an up-to-date review of the previous cases in the field as well with a review of the literature of post adolescent neuroblastoma.

Neuroblastoma of the elderly, an oncologist's nightmare: case presentation, literature review and SEER database analysis

Neuroblastoma is considered a pediatric malignancy as over 95% of cases are diagnosed in patients ≤10 years old. This cancer is extremely rare in elderly patients. We conducted a Surveillance, Epidemiology, and End Results (SEER) database analysis in the USA between 1973–2007 that revealed only 35 elderly patients (>60 years of age) with neuroblastoma of whom only 2 patients had primary mediastinal neuroblastoma. There is a paucity of treatment and survival outcomes data for the elderly owing to the rarity of neuroblastoma in this population. Currently there are no standard guidelines or protocols for treatment of adult neuroblastoma. We report a rare and challenging case of an 86-year old patient presenting with mediastinal neuroblastoma and syndrome of inappropriate antidiuretic hormone secretion (SIADH) successfully treated with resection. Herein, we also provide a review of the literature and updated survival data on neuroblastoma based on results of our SEER database review.