Splenomegaly during oxaliplatin-based chemotherapy: impact on blood parameters and anti-neoplastic treatment.

Background: Oxaliplatin induces splenomegaly, which can cause blood sequestration and relevant cytopenia, leading to further dose reductions and schedule modifications of chemotherapy. Here, we aimed to explore the changes of spleen volume induced by oxaliplatin as well as its impact on blood parameters and anti-neoplastic treatment in patients with colon cancer.

Methods: We conducted a retrospective analysis of patients with resectable stage II-IV colon cancer who were treated with oxaliplatin and capecitabine at our institution from January 2016 to December 2017. Laboratory tests and computed tomographic (CT) data before, during and up to 18 months after the end of chemotherapy were extracted. Spleen volume was determined by volumetric measurements. Splenomegaly was defined as an over 30% increase in spleen volume from baseline.

Results: Out of 144 patients, 102 patients (70.8%) developed splenomegaly, and 75 (73.5%) recovered at 18 months after the end of chemotherapy. Higher cumulative dose intensity of oxaliplatin (P=0.001) and higher baseline platelet count (P=0.045) were risk factors associated with splenomegaly. Compared to those without splenomegaly, splenomegaly patients experienced more severe reduction in platelet (P<0.001), erythrocyte (P=0.010), neutrophil (P=0.002) and lymphocyte (P=0.006) counts and were more likely to undergo dose reductions of oxaliplatin (21.6% 7.1%, P=0.038) as well as interruptions of chemotherapy (18.6% 4.8%, P=0.040) due to thrombocytopenia.

Conclusions: Splenomegaly was a common and partly irreversible side effect of oxaliplatin-based therapy in patients with colon cancer. It is correlated with more severe pancytopenia and might exert a negative impact on the efficacy of anti-neoplastic treatment.