Complete response of sunitinib therapy for renal cell cancer recurrence in the native kidney after renal transplantation: a case report

Renal Cell Carcinoma and Kidney Transplantation: A Narrative Review

Kidney transplant recipients (KTRs) are at increased risk of developing renal cell carcinoma (RCC). The cancer can be encountered at different steps in the transplant process. RCC found during work-up of a transplant candidate needs treatment and to limit the risk of recurrence usually a mandatory observation period before transplantation is recommended. An observation period may be omitted for candidates with incidentally discovered and excised small RCCs (<3 cm). Likewise, RCC in the donor organ may not always preclude usage if tumor is small (<2 to 4 cm) and removed with clear margins before transplantation. After transplantation, 90% of RCCs are detected in the native kidneys, particularly if acquired cystic kidney disease has developed during prolonged dialysis. Screening for RCC after transplantation has not been found cost-effective. Treatment of RCC in KTRs poses challenges with adjustments of immunosuppression and oncologic treatments. For localized RCC, excision or nephrectomy is often curative. For metastatic RCC, recent landmark trials in the nontransplanted population demonstrate that immunotherapy combinations improve survival. Dedicated trials in KTRs are lacking. Case series on immune checkpoint inhibitors in solid organ recipients with a range of cancer types indicate partial or complete tumor response in approximately one-third of the patients at the cost of rejection developing in ~40%.

Angiosarcoma in an arteriovenous fistula after kidney transplantation: Case report and review of treatment options

We present a patient with an angiosarcoma in an arteriovenous fistula and we reviewed current treatments for angiosarcomas. We extended the systematic review by Oskrochi et al. on this topic in 2015, using the same search query. We searched systematically OVID, EMBASE and PubMed from April 2015 until January 2020 with the aim to update the state of the art in managing this rare but serious condition. We retrieved 12 new case reports about 11 unique patients. Mean age was 61.5 ± 11 years. Six arteriovenous fistulas had failed spontaneously. Two fistulas were operatively closed post-transplant. Nine patients (81.8%) were receiving ongoing immunosuppressive therapy. Pain and growing lesions, mass or swelling were the most frequent symptoms. Angiosarcoma mostly presents with a nonspecific clinical picture of pain, growing lesions and swelling of a previously normal arteriovenous fistula. Amputation of the limb was most frequently conducted as treatment in localized disease. Treatment of systemic disease included supportive care, chemotherapy, especially with paclitaxel and change of immunosuppressive regimen. Metastasized angiosarcoma has a very poor prognosis. Classical chemotherapy has rather low response rates. There is limited data supporting treatment of angiosarcomas with tyrosine kinase inhibitors or immunotherapy. Further comparative research is needed.

Model-based assessment of pharmacokinetic changes of sunitinib, tacrolimus, and everolimus in a patient with metastatic renal cell carcinoma after renal transplantation

The safety of the coadministration of sunitinib with tacrolimus and everolimus with regard to therapeutic drug monitoring has not been demonstrated. Here, we report a patient who showed high sunitinib concentrations, in addition to pharmacokinetic changes in tacrolimus and everolimus after sunitinib therapy. A living-donor renal transplant patient treated with tacrolimus and everolimus was diagnosed with pulmonary and pleural metastases of renal cell carcinoma. The patient received sunitinib therapy (37.5 mg/day, 2 weeks on and 1 week off). This patient exhibited a high total sunitinib concentration (sunitinib, 105.8 ng/mL; N-desethyl sunitinib, 27.9 ng/mL) on day 10 postinitiation and experienced grade 3 diarrhea. The observed sunitinib concentrations were a little higher than those reported in the 421C>A polymorphism of the ATP-binding cassette subfamily G member 2 gene carrier. The observed concentrations of both tacrolimus and everolimus gradually decreased compared with the Bayesian-predicted values after the onset of sunitinib therapy, and the doses of tacrolimus and everolimus were increased. Careful therapeutic drug monitoring of sunitinib, tacrolimus, and everolimus concentrations is necessary during combination therapy, especially after episodes of diarrhea.