To describe thyroid dysfunction (TD) and pituitary/adrenal dysfunction (PAD) in a cohort of individuals in a community setting receiving PD1 inhibitors; including incidence in a real-world setting, and outcomes; including need for hormone replacement, and survival.
A database search was undertaken to determine individuals in our service who had received a PD1 inhibitor. Data were collected retrospectively including date of development of endocrine abnormalities, treatment required, pattern of abnormality (e.g. hypothyroid, hyperthyroid), and oncological outcome (date of progression and death).
A cohort of 100 patients was identified as having been prescribed PD1 inhibitors by the date of the database search (April 2017). Tumour types were melanoma (59%), non-small cell lung cancer (27%), other solid tumours (11%). All had stage IV disease. Age range was 22-88 years (median 69).
Incident TD occurred in 29 individuals. Median time to abnormality was 14 weeks (2-52 weeks). The predominant pattern was hypothyroid (15/29). 9/15 required thyroxine. 4/29 were hyperthyroid, only 1 required carbimazole. 14 had TD at baseline. In a Kaplan-Meier analysis, there was no association between incident TD and survival. Prior to controlling for treatment duration there was a trend towards association (p=0.14). In an attempt to control for survival bias, cases were defined as those who survived 3 months on treatment and developed TD prior, in this analysis there was no association between TD and survival (p=0.83).
5 individuals had PAD. All required cortisone replacement. PAD occurred between 2-36 weeks on treatment. 2/5 had MRI Brain scans, 1 was normal and one showed possible pituitary metastasis. Survival analysis was not done due to small numbers.
TD is common in a community cohort on PD1 inhibitors, PAD is rare. 1/3 of TD patients and all PAD patients required hormone replacement. Monitoring of hormone levels is important for patient wellbeing.