Isolated testicular involvement in pediatric lymphoma is rare and poses diagnostic challenges. In this study, the case of an isolated testicular B-lymphoblastic lymphoma in a 9-year-old boy is discussed with an emphasis on the difficulties in diagnosing and treating such an unusual presentation. This example illustrates the importance of considering lymphoblastic lymphoma in the differential diagnosis of an unidentified source of testicular enlargement. Furthermore, it highlights the possible efficacy of systemic chemotherapy with or without surgical excision. The article advances our knowledge of this unusual clinical situation.

Lymphoblastic lymphoma is a rare and aggressive form of non-Hodgkin lymphoma (NHL). The tumor can derive from T-cell or B-cell and is clinically similar to acute lymphoblastic leukemia with minimal to no bone marrow involvement distinguishing the two. We present a rare case of lymphoblastic lymphoma originating from the paranasal sinuses. A 40-year-old male presented to the emergency department and was diagnosed with right-sided acute sinusitis complicated by pre-septal cellulitis. After failing medical management, he underwent endoscopic sinus surgery. Pathologic analysis of nasal contents stained for CD79a, CD34, and PAX5, suggesting a B-cell lymphoblastic lymphoma (B-LBL). He was referred to hematology-oncology and was treated with hyperfractionated cyclophosphamide, vincristine, Adriamycin, dexamethasone (Hyper-CVAD). Short-term follow-up has thus far demonstrated near-complete resolution of the tumor. Non-Hodgkin lymphomas of the paranasal sinuses are rare, and B-cell lymphoblastic lymphomas comprise just 0.3% of adults with NHL. Immunohistochemical phenotyping for B-LBL is typically positive for B-cell markers CD19, CD20, CD22 and CD79a. Classic treatment involves a chemotherapy regimen of Hyper-CVAD with an overall survival rate of 66%. B-cell lymphoblastic lymphoma is rarely reported in the paranasal sinuses. A thorough history and physical exam along with a complete workup, including biopsies with histopathological and immunohistochemical analysis, needs to be obtained. Little is known about its prognosis when the primary site is within the paranasal sinuses, and therefore, patients need prompt and aggressive treatment when the diagnosis is made.

Primary testicular B-lymphoblastic lymphoma is a rare entity. Primary testicular Ph-positive B lymphoblastic lymphoma was not reported before. We reported a 27-year-old man with primary testicular Ph-positive B lymphoblastic lymphoma, for which fluorescent in-situ hybridization (FISH) for the Philadelphia chromosome was not performed at the initial hospitalization. The patient showed manifestation of Ph-positive acute lymphoblastic leukemia at relapse. In this report, we reviewed the current literature about primary testicular B-lymphoblastic lymphoma, Ph-positive lymphoma and Ph-positive clone evolution. This report has 3 meanings. First: This is first report on primary testicular Ph-positive B lymphoblastic lymphoma. Second: This shows the importance of cytogenics for lymphoma treatment. Third: This implies Philadelphia-positive subclone evolution.