Postchemotherapy retroperitoneal lymph node dissection in patients presenting with very high HCG levels

Choriocarcinoma germ cell tumors are rare and usually present with significantly elevated human chorionic gonadotropin (hCG) levels. When curable, it is felt to be largely a result of chemotherapy. We sought to determine the histologic characteristics for those undergoing postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) and compare them with metastatic nonseminomatous germ cell tumor (NSGCT) patients with similarly elevated hCG levels.

We reviewed medical records of men undergoing PC-RPLND between 1988 and 2017 with postorchiectomy, preinduction chemotherapy hCG levels greater than 50,000 mIU/ml. They were stratified by primary tumor histology: Pure choriocarcinoma and mixed NSGCT. Clinical, pathologic, and serologic data were reported and logistic regression was used to assess for predictors of necrosis in the PC-RPLND specimen.

Our cohort consisted of 108 men. The mixed group (n = 91) had a median hCG of 165,177 mIU/ml, a postchemotherapy node size of 4.7 cm, of whom 19.8% also received salvage chemotherapy prior to RPLND. The pure choriocarcinoma group (n = 17) had a median hCG of 170,267 mIU/ml, a node size of 5.1 cm, of whom 17.6% received salvage chemotherapy. 88.2% of patients with choriocarcinoma had necrosis in the PC-RPLND specimen compared with 29.7% of the mixed NSGCT group (P = <0.0001). Controlling for salvage chemotherapy use, prechemotherapy hCG, node size and marker status, choriocarcinoma patients were 20 fold more likely to have necrosis on RPLND specimen (Odds ratio 20.68 [95% confidence interval 5.279-81.114]).

While PC-RPLND is appropriate in patients with residual masses after chemotherapy, patients with pure choriocarcinoma presenting with significantly elevated hCG levels represent a unique patient population where necrosis is found more often than anticipated.