Autoimmune rhabdomyolysis and a multiorgan display of PD-1 inhibitor induced immune related adverse events during treatment of metastatic melanoma

Background Programmed death-1 (PD-1) inhibitors are among the immunotherapies that have revolutionized our approach to treating several cancers. These novel agents act by blocking PD-1 receptor/PD-1 ligand interactions that would otherwise allow tumor cells to evade host immune destruction by inhibiting response of cytotoxic T-lymphocytes. They are overall well tolerated, though they have been associated with a constellation of immune mediated adverse events (irAEs). Case presentation We present a case of rare nivolumab mediated adverse events in a patient with nodular recurrence of melanoma. The patient presented with rhabdomyolysis and shortly thereafter developed a constellation of immune-mediated organ derangements. This case further demonstrates the utility and effectiveness of steroid therapy in the setting of irAEs despite our patient’s eventual poor clinical outcome. While PD-1 inhibitors have revolutionized the treatment of several cancers, they require vigilance by the clinician for early detection and treatment of uncommon but potentially fatal irAEs. Conclusions PD-1 inhibitors are now widely used in a multitude of cancer types including melanoma, advanced non-small cell lung cancer, metastatic renal cell carcinoma, and Hodgkin lymphoma amongst others. While these agents are often well tolerated, they are associated with a unique profile of immune-related toxicities that can cause significant morbidity and mortality. Education of both patients and healthcare providers is essential for diagnosis and treatment of these adverse events early in their course. This case highlights the uncommon but potentially serious PD-1-associated toxicity of myopathy and rhabdomyolysis along with other organ involvement and is directly applicable to use of these agents in patients with advanced cancers.

Brachytherapy as salvage treatment for local nodular recurrence of prostate cancer.

86 Background: Men diagnosed with adenocarcinoma of the prostate treated with radical prostatectomy (RP) have a 10% risk of developing local recurrence within 10 years. While the majority of these recurrences are biochemical failures with no foci of disease, we report on a series of 7 patients who had nodular recurrences in the post-surgical bed and subsequently underwent low-dose rate (LDR) brachytherapy as salvage therapy. Methods: Patients who were initially treated with RP and subsequently with salvage LDR I-125 brachytherapy for a nodular recurrence were included in this series. All patients failed biochemically within 10 years of RP and received no other adjuvant or salvage treatment by choice. Nodular recurrences were biopsy confirmed adenocarcinoma, and patients had no evidence of nodal or distant metastasis on imaging or bone scan. All patients consented to salvage with LDR brachytherapy. Follow up post-salvage was at least every 6 months with a serial PSA. Results: Seven patients underwent salvage LDR brachytherapy with median age of 74 (range 63-77) at time of salvage. The median pre-salvage PSA was 4.56. The biopsy Gleason score of the nodular recurrences was 7 or 8. Median volume of nodular recurrence was 16cc, median number of sources was 30, median D90 for nodule was 155.02 Gy, and median rectum V100 was 0.01. Compared to baseline prior to salvage, patients have reported no additional urinary symptoms or sexual side effects from salvage. Patients have been followed for a median of 28 months post-salvage (range 4-48 months) with a median PSA at last follow up of 1.05. Conclusions: This report presents the first known case series of prostate cancer patients treated with RP who developed local nodular recurrences which were then treated with LDR brachytherapy. For patients who develop a nodular recurrence with no other evidence of distant metastases, LDR brachytherapy offers a novel salvage option. No significant financial relationships to disclose.