# Testicular Lymphoma > Testicular lymphoma for NEET-PG Surgery: commonest tumour over 60, DLBCL histology, CNS relapse risk, R-CHOP with intrathecal prophylaxis and orchidectomy. - Canonical URL: https://prepelephant.com/topics/neet-pg/surgery/testicular-lymphoma - Exam / course: NEET-PG · Subject: Surgery - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Testicular Lymphoma", PrepElephant, https://prepelephant.com/topics/neet-pg/surgery/testicular-lymphoma ## Direct answer Primary testicular lymphoma is the commonest testicular tumour in men over 60, typically diffuse large B-cell lymphoma (DLBCL) presenting as a painless, rapidly enlarging testis that is easily mistaken for seminoma. It is the most aggressive lymphoma site in terms of relapse pattern, with a marked tendency to spread to the contralateral testis, the central nervous system, skin and Waldeyer's ring. Treatment combines orchidectomy (which provides full tissue for diagnosis), R-CHOP chemotherapy, intrathecal or systemic CNS prophylaxis, and consideration of contralateral testicular radiotherapy. ## What you must remember - Any testicular tumour in a man over 60 is lymphoma until proven otherwise; DLBCL is the dominant histology. - Bilateral involvement is far commoner than with germ cell tumours — lymphoma eventually involves the contralateral testis in a substantial fraction of patients. - CNS relapse (parenchymal brain and leptomeningeal) is a signature failure pattern, driving routine intrathecal prophylaxis. - Ann Arbor staging with CT, PET and bone marrow assessment (plus CSF examination in many protocols) replaces the germ cell TNM approach. - Spermatic cord invasion and epididymal involvement are frequent, and the mass is often disproportionately large and painless. - In children, by contrast, lymphoma and leukaemia are the commonest secondary (metastatic) tumours of the testis — a classic distinction examiners test. - Relapses tend to be late, beyond two years, which is unusual for other extranodal lymphomas. ## How the diagnosis actually unfolds A 68-year-old reports three months of painless left testicular enlargement; there is no fever or weight loss. Ultrasound shows a large, homogeneous, hypoechoic infiltrating mass replacing the testis, extending into the epididymis — a pattern that should raise lymphoma, since germ cell tumours are more often heterogeneous. The surgeons proceed with inguinal orchidectomy; frozen section may change the intraoperative plan, because lymphoma needs generous tissue for flow cytometry and immunohistochemistry (CD20 positivity confirms B-cell lineage), and a diagnosis of lymphoma makes extensive retroperitoneal dissection unnecessary. Staging is then haematological: CT neck-chest-abdomen-pelvis, PET-CT where available, bone marrow biopsy, CSF analysis, LDH and beta-2 microglobulin. Markers AFP and beta-hCG are usually normal, which itself argues against germ cell tumour. Management is R-CHOP with CNS prophylaxis (intrathecal methotrexate and/or high-dose systemic methotrexate-containing regimens per protocol), and many centres add contralateral testicular radiotherapy (commonly in the order of 25-30 Gy) because the blood-testis barrier shelters the gonad from systemic chemotherapy. Outcomes are guarded, worse than stage-matched nodal DLBCL, and late relapses justify prolonged surveillance — a fact that distinguishes testicular lymphoma from most solid tumours in the exam hall. ## Where students slip The reflex answer "painless testicular swelling in an older man equals seminoma" is the trap; seminoma peaks at 35-45 years, and beyond 60 lymphoma overtakes it. The second slip is staging: ordering AFP, beta-hCG and abdominal CT for retroperitoneal nodes is germ cell logic; lymphoma demands Ann Arbor staging, PET and marrow. Third, candidates forget the two sanctuary sites — the brain and the contralateral testis — that explain the design of prophylaxis. Finally, in a child with a testicular mass and a known leukaemia or lymphoma, the lesion is likely a leukaemic infiltrate rather than a new primary; the viva answer is "treat the systemic disease, consider irradiation or chemotherapy infiltration, not orchidectomy first". ## Frequently asked questions ### What is the most common testicular tumour in a man over 60? Primary testicular diffuse large B-cell lymphoma. Germ cell tumours dominate from adolescence to middle age, but lymphoma leads in the elderly. ### Which histology characterises primary testicular lymphoma? Diffuse large B-cell lymphoma in the great majority of cases, confirmed by CD20 positivity on immunohistochemistry, with flow cytometry on fresh tissue. ### Why does testicular lymphoma need CNS prophylaxis? Because the brain and leptomeninges are favoured relapse sites, with CNS recurrence reported in up to a fifth or more of historically untreated patients; intrathecal or systemic methotrexate-based prophylaxis reduces this. ### Why is contralateral testicular radiotherapy considered? The blood-testis barrier excludes systemic chemotherapy from the gonad, leaving the opposite testis at risk as a chemoresistant sanctuary site; radiotherapy of around 25-30 Gy is used to ablate it. ### How does testicular lymphoma appear on ultrasound? Typically as a large, homogeneous, hypoechoic mass infiltrating the testis, often with epididymal and spermatic cord extension, compared with the more heterogeneous appearance of germ cell tumours.