Objective To investigate the changing trend and correlation of platelet count and spleen diameter in patients with digestive system malignancy receiving oxaliplatin-based chemotherapy.

Methods We retrospectively analyzed clinical data of 72 patients with digestive system cancer, recorded and analyzed platelet count and spleen diameter during and after oxaliplatin-based chemotherapy.

Results The incidence of thrombocytopenia in all patients was 65.3%. The median time of thrombocytopenia after the beginning of chemotherapy was 2.53±0.49 months, and the median cumulative dose of oxaliplatin was 520±35.81 mg/m²; the median time of lowest platelet count after the beginning of chemotherapy was 4.03±0.49 months, and the median cumulative dose of oxaliplatin was 780±36.32 mg/m². Splenomegaly occurred in 52(72.2%) patients during the follow-up. The median increase rate was (18.82±0.01)%. The median time of splenomegaly after the beginning of chemotherapy was 2.15±0.19 months, the median time for the largest spleen diameter was 4.68±2.89 months; after the end of chemotherapy, the median time for spleen contraction was 3.28±0.44 months, and the median time for spleen recovery was 8.80±1.05 months.

Conclusion Oxaliplatin-based chemotherapy can cause thrombocytopenia and splenomegaly, and it is difficult to recover to baseline for a long time after the end of chemotherapy. The increase of spleen diameter was positively correlated with splenomegaly and thrombocytosis.