Calcitriol-mediated hypercalcemia as an immune-related adverse event in a patient receiving nivolumab and ipilimumab for metastatic renal cell carcinoma, case report

Bone Metabolism Effects of Medical Therapy in Advanced Renal Cell Carcinoma

The medical therapy of advanced renal cell carcinoma (RCC) is based on the use of targeted therapies, such as tyrosine kinase inhibitors (TKI) and immune-checkpoint inhibitors (ICI). These therapies are characterized by multiple endocrine adverse events, but the effect on the bone is still less known. Relatively few case reports or small case series have been specifically focused on TKI and ICI effects on bone metabolism. However, the importance to consider these possible side effects is easily intuitable because the bone is one of the most frequent metastatic sites of RCC. Among TKI used in RCC, sunitinib and sorafenib can cause hypophosphatemia with increased PTH levels and low-normal serum calcium levels. Considering ICI, nivolumab and ipilimumab, which can be used in association in a combination strategy, are associated with an increased risk of hypocalcemia, mediated by an autoimmune mechanism targeted on the calcium-sensing receptor. A fearsome complication, reported for TKI and rarely for ICI, is osteonecrosis of the jaw. Awareness of these possible side effects makes a clinical evaluation of RCC patients on anticancer therapy mandatory, especially if associated with antiresorptive therapy such as bisphosphonates and denosumab, which can further increase the risk of these complications.

Endocrine-related adverse conditions in patients receiving immune checkpoint inhibition: an ESE clinical practice guideline

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment but are associated with significant autoimmune endocrinopathies that pose both diagnostic and treatment challenges. The aim of this guideline is to provide clinicians with the best possible evidence-based recommendations for treatment and follow-up of patients with ICI-induced endocrine side-effects based on the Grading of Recommendations Assessment, Development, and Evaluation system. As these drugs have been used for a relatively short time, large systematic investigations are scarce. A systematic approach to diagnosis, treatment, and follow-up is needed, including baseline tests of endocrine function before each treatment cycle. We conclude that there is no clear evidence for the benefit of high-dose glucocorticoids to treat endocrine toxicities with the possible exceptions of severe thyroid eye disease and hypophysitis affecting the visual apparatus. With the exception of thyroiditis, most endocrine dysfunctions appear to be permanent regardless of ICI discontinuation. Thus, the development of endocrinopathies does not dictate a need to stop ICI treatment.