Experience with pembrolizumab in a renal transplant patient with advanced lung cancer: a case report and review.

The treatment of non-small cell lung cancer (NSCLC) has undergone a change due to the advancement of new therapies, like immune checkpoint inhibitors (ICIs), including pembrolizumab. A 64-year-old woman received a kidney transplant in 2012 due to chronic kidney disease secondary to glomerulosclerosis, diagnosed in 2020 with stage IV NSCLC due to metastasis in the contralateral lung, with PD-L1 expression of 98%, starting treatment with ICIs, despite presenting a graft rejection risk around 40%. After 3 ICI cycles, the patient presented a partial response, with good tolerance to treatment and no signs of graft failure. ICIs were maintained for 19 cycles, until disease progression was observed on a reassessment computed tomography, with a progression-free interval of 18 months, with no evidence of treatment rejection. In transplant patients diagnosed with some type of tumor, antineoplastic therapies may be less effective than in the general population. The current evidence derives from observational studies and case series, since this patient population was excluded from clinical trials, suggesting that the use of ICIs in patients with kidney transplants can lead to acute graft rejection. This is still a controversial issue, it is necessary to improve the quality of the data, with the implementation of clinical trials or prospective studies.