Rare case of life-threatening thrombocytopenia occurring after radiotherapy in a patient treated with immune checkpoint inhibitor

Abstract

Immune checkpoint inhibitors (ICIs) improve significantly outcome of patients with advanced renal cancer. Although immune-related adverse events involve frequently skin, digestive tract, lung, liver and endocrine organs, haematological toxicities are rare. We describe the case of a patient with metastatic renal cancer who was treated with nivolumab. Eight courses of nivolumab were administered without any toxicity; brain metastases were then diagnosed and treated with stereotactic radiotherapy. As the extra-cranial disease was stable, the ninth course of nivolumab was administered 5 days after the end of radiotherapy. One week later, he presented with rectal and nasal bleeding in a context of severe thrombocytopenia (1000/mm3). High dose of steroids and intravenous immunoglobulin reversed slowly the thrombocytopenia. This case highlights the possibility of life-threatening thrombocytopenia with ICIs. Interestingly, the close time relation with radiotherapy highlights a potential interaction, warranting a close follow-up of patients in this situation.

Thrombocytopenia and hyperprogression after radiotherapy and camrelizumab treatment in an esophageal cancer patient with increased JAK2 gene copies: a case report

“…We found previous reports of fatal immune thrombocytopenia related to ICI administered around the time of RT. Notably, the reported patients displayed no hematological irAEs during treatment with mono-ICI, yet a rapid decrease in platelet count was observed following intracranial radiation (22,23). RT induces tumor cell apoptosis and inflammation, which may activate macrophages that can mediate platelet destruction.…”

Immune checkpoint inhibitor-related thrombocytopenia: incidence, risk factors and effect on survival

“…Thrombocytopenia is an uncommon and therefore poorly characterized irAE; severe cases can even be life-threatening [5]. Severe cases of ICI-related immune thrombocytopenia have been reported among patients with non-small cell lung cancer (NSCLC), usually associated with having elevated platelet-associated immunoglobulin indicating an immune-driven mechanism, as well as in melanoma and renal cell carcinoma [6][7][8][9]. ICI-related thrombotic thrombocytopenic purpura (TTP) has been found to occur rarely in each of these cancer types [10][11][12].…”