A 59-year-old man presented with a painless testicular mass and underwent a radical orchiectomy. The resected specimen showed a 5-cm-sized, white-yellow and homogenous solid mass in the testicular parenchyma. Histologically, the central part of the tumor exhibited typical features of seminoma. The peripheral part of the tumor exhibited diffuse infiltration of small, monotonous lymphoid cells involving the tunica albuginea. The monotonous lymphoid cells were immunoreactive for CD20, CD79a, CD5, and CD23, and negative for CD3, CD10, and cyclin D1. Kappa light chain restriction was detected on flow cytometry using the resected specimen. Considering the circulating lymphoid cell count of >5.0×103/µL, we diagnosed the peripheral component of the tumor as an infiltration of chronic lymphocytic leukemia. This extremely rare combination of seminoma and lymphoid neoplasm should be considered in the differential diagnosis of classic seminoma with extensive lymphoid reaction in tumors arising in elderly patients.
Thymoma is the most common neoplasm of the anterior mediastinum and has malignant potential. Germ cell tumors (GCTs) found in the anterior mediastinum are usually benign, and malignant GCTs, such as seminomas, are rare. Histologically, mediastinal seminoma is indistinguishable from testicular seminoma except for site-associated morphological features such as lymphoid follicular hyperplasia. Therefore, excluding metastasis is very important. Recently, we treated a young adult patient with multiple thymic masses that occurred simultaneously. The patient underwent a thymectomy for the removal of the mediastinal masses, one of which was diagnosed as type B2 invasive thymoma, and two of which were diagnosed as primary mediastinal seminomas with massive follicular hyperplasia. The patient received adjuvant chemotherapy after surgical resection. To our knowledge, this is the first description of a thymoma and a mediastinal seminoma occurring simultaneously in the thymus. We present this case along with a literature review.
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Primary germ cell tumours of the mediastinum: A review with emphasis on diagnostic challenges Alexander Fichtner, Alexander Marx, Philipp Ströbel, Felix Bremmer Histopathology.2024; 84(1): 216. CrossRef
Combined type A thymoma and yolk sac tumour of the mediastinum Dong Sheng, Yu-Chen Han Pathology.2024; 56(6): 927. CrossRef
Combined Thymic Epithelial Neoplasms – a Review Annikka Weissferdt International Journal of Surgical Pathology.2023; 31(6): 917. CrossRef
Primary mediastinal seminoma presenting with paraneoplastic anti-Hu encephalitis: a case report and literature review Chelsey M. Williams, Derek B. Allison, Adam B. Coleman, Roshmita Bardhan, Jordan D. Miller, Zin W. Myint Frontiers in Oncology.2023;[Epub] CrossRef
Primary mediastinal seminoma with florid follicular lymphoid hyperplasia: a case report and review of the literature Charlotte Holmes, Peh Sun Loo, Sion Barnard Diagnostic Pathology.2021;[Epub] CrossRef
BACKGROUND KIT and PDGFRA are tyrosine kinase receptors.
Stem cell factor/KIT-mediated signaling plays a role in normal spermatogenesis, and the alteration of KIT is important in the pathogenesis of seminomas/dysgerminomas (SD). METHODS: To determine the role of expression and mutation of the KIT and PDGFRA genes, we analyzed 16 seminoma cases, 4 spermatocytic seminoma (SS) cases and 8 dysgerminoma cases for KIT and PDGFRA expression and mutation of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) using PCR-SSCP methods. RESULTS: KIT was immunohistochemically positive in all 24 SD cases, and one of four (25%) SS cases. PDGFRA was immunohistochemically evident in 16 of the 24 (66.6%) SD cases, and two of the four (50%) SS cases. KIT expression was significantly reduced in SS compared with seminoma (p=0.0035). Four cases (14.3%) displayed mutation in KIT exon 17 or PDGFRA exon 12.
Distant metastasis was present in three cases (10.7%), one of which had a nonsense mutation in KIT. CONCLUSIONS: These results indicate that KIT is expressed in the majority of SD cases, but not in most SS cases. However, there was no significant correlation between the clinicopathologic features and mutation or expression of KIT and PDGFRA.
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Expression of DOG1, PDGFRA, and p16 in Gastrointestinal Stromal Tumors Sung Hee Jung, Kwang Sun Suh, Dae Young Kang, Dong Wook Kang, Young-Beum Kim, Eun-Sun Kim Gut and Liver.2011; 5(2): 171. CrossRef
A fine needle aspiration biopsy specimen of a retroperitoneal mass in a 26-year-old man who had had an orchiectomy for seminoma was submitted for cytologic evaluation. Cytologic features of the specimen included uniform neoplastic cells found singly or in groups of several cells intermingled with lymphocytes in a characteristic foamy, lacelike background. These cells varied from 10 to 20 m in diameter. The nuclei were round to ovoid with fine or reticular chromatin and one or more prominent nucleoli. The poorly defined cytoplasm stained pale-blue or blue with cytoplasmic vacuoles. The cytologic appearance was consistent with seminoma. Documented reports of the cytological appearance of seminoma are rare. The diagnosis of primary gonadal seminoma by fine needle aspiration biopsy is probably not indicated since the treatment of a primary gonadal tumor, regardless of its histogenesis, requires surgical resection. However, fine needle aspiration biopsy is extremely valuable in the diagnosis of extragonadal as well as metastic and recurrent seminoma.
Fine needle aspiration cytologyof a pulmonary mass was performed on a 51-year-old man who had a left testicular mass. Cytologic features were composed of a homogeneous population of malignant cells associated with a background of foamy and lacelike material. The cellular features were characterized by monomorphous cell proliferation of relatively regular large cells, generally isolated or grouped. Occasionally, fine branching stroma with large tumor cells and scanty lymphocytes were noted. The tumor cells had a round, regular nucleus, prominent round nucleoli, and a thin rim of cytoplasm containing large vacuoles or lacunae filled with glycogen. The fine needle aspiration cytologic diagnosis was highly consistent with metastatic seminoma from testis and less likely primary or other metastatic carcinoma. The diagnosis of resected testicular mass was classic seminoma. Despite the fact that cytopathologists were not familiar with diagnosis of seminoma due to clinician's lack of interest in fine needle aspiration cytology of germ cell tumors including seminoma, it appears that a diagnosis of this tumor should not be problematic in cytologic material if specific histologic criteria are applied.
Fine needle aspiration cytology of the cervical lymph node was performed in a 63-year-old man who had had an orchiectomy for seminoma one year ago. The tumor cells were arranged in loose clusters, occasional sheets, or single cells. The nuclei were round to ovoid with fine or reticular chromatin, and had one or more prominent nucleoli. These cells were intermingled with lymphocytes in a characteristic foamy, lacelike background. Documented reports of the cytologic appearance of the seminoma are rare, especially in the metastatic lesion. The diagnosis of primary gonadal seminoma by fine needle aspiration cytology is probably not indicated since the treatment of primary gonadal tumor requires surgical resection. Because of the characteristic cytologic features, fine needle aspiration cytology may be helpful in evaluation of the extent of tumor spread in the patients with testicular tumors.
Individuals with Down syndrome have a susceptibility to neoplastic transformation, increased risk of chronic leukemia and central nervous system tumors. Recently, an increased number of cases of testicular germ cell tumors have been reported in individuals with Down syndrome, with more than forty cases in the literature. Here we report the first Korean case of seminoma with Down syndrome, in a 19-year-old institutionalized man who presented with painful scrotal swelling. Percutaneous needle biopsy showed histology of seminoma with invasion to the adjacent epididymis. Both testes were orthotopic. He underwent orchiectomy of the affected side, and the surgical staging was stage I seminoma with complete resection. We emphasize that the physician and nursing staff should be aware of the increased incidence of testicular seminoma in Down syndrome, because testicular seminoma might be misinterpreted as a scrotal infection with subsequent needle biopsy, which is contraindicated to avoid possible lymphatic metastasis.