Spontaneous splenic haematoma in a multiple myeloma patient receiving pegfilgrastim support.

Growth factors are a significant advance in the supportive care of patients with cancer with a wide range of indications. Frequent side effects of G-CSF include bone pain, headache, fatigue and nausea. We report a case of subcapsular splenic haematoma following pegfilgrastim administration in a 65-year old patient with multiple myeloma. Proposed mechanisms accounting for splenic enlargement include extramedullary haemopoiesis, intrasplenic infiltration by mature and immature myeloid cells and intrasplenic stem cell homing and proliferation. The risk of spontaneous splenic rupture is difficult to quantify. Physicians should be aware of this life-threatening condition and early diagnosis can be difficult since anemia and splenomegaly are common findings in haematologic patients.