Management of residual nonretroperitoneal disease in nonseminomatous germ-cell tumors (NSGCT).

5034 Background: The management of NSGCT patients (pts) with post-chemotherapy residual non-retroperitoneal disease (RP) remains unsettled. Decisions for surveillance vs surgical resection are commonly steered by pathology from retroperitoneal lymph node dissection (RPLND). Data is limited in pts who do not require RPLND (normal or normalized RP post-chemo). Methods: The prospectively maintained Indiana University testicular cancer database was queried for pts with metastatic NSGCT who completed first-line chemotherapy and had residual extra-RP disease without residual RP disease. Pts with post-chemo non-RP surgical resection were included. Results: 134 pts met eligibility. Median age at diagnosis was 28.6 (range, 16.2-51.5). Primary tumor predominant histology was embryonal (35.1%), mixed (25.4%), seminoma (2.2%), yolk sac (9.7%), choriocarcinoma (15.7%), teratoma (11.2%). 76 pts (56.7%) had teratoma in the primary tumor. Metastatic sites at diagnosis were RP (15.7%), mediastinal LN (8.2%), lung (28.4%), liver (11.2%), bone (6.7%), brain (21.6%). Those with RP mets at diagnosis had normalization of RP nodes after chemo. IGCCCG risk was good in 57, intermediate in 21, and poor in 56 pts. Median pre-chemo AFP was 66 (0.9-467,000). hCG was 960.5 (0.5-1,300,000). First-line chemo was BEPX4 in 68, BEPx3 in 29, EPX4 in 10, VIPX4 in 9, and other in 18 pts. All pts had surgical resection of non-RP disease. None had RPLND. 84 pts had lung nodule resection, 16 had mediastinal LN, 8 had cervical LN, 5 had liver, 6 had bone, and 20 had brain met resection. Of the 76 pts with teratomatous elements in the orchiectomy, 41 (53.9%) had teratoma and 24 (31.6%) had non-teratoma GCT in post-chemo non-RP surgical specimens. Of the 58 pts without teratoma in the orchiectomy, 9 (15.5%) had teratoma and 34 (58.6%) had non-teratoma GCT in the non-RP surgical resection specimens. Teratoma in the orchiectomy was a predictor of non-RP teratoma (Fisher’s exact test P<0.0001). Conclusions: The presence of teratoma in orchiectomy predicts teratoma in residual post-chemo non-RP disease in pts who do not undergo RPLND. The absence of teratoma in orchiectomy should not preclude resection of residual non-RP disease given a subset of patients had persistent GCT. [Table: see text]