Endocrinopathies in patients undergoing treatment with Immune Checkpoint Inhibitors at Royal Cornwall Hospital.


Session type:

Dhruv Abhi1
1Royal Cornwall Hospitals NHS Trust



Immune checkpoint inhibitors such as CTLA 4 inhibitors and PD1 and PD-L1 inhibitors are being increasingly used for treatment of malignant melanomas, Non small cell lung cancers, Renal cell cancers along with being investigated for use in several other tumour sites. Despite clinical benefits, they have been known to cause certain Immune related adverse effects (IrAEs) which may be dermatological, gastrointestinal, endocrine, or other immune phenomenon. The endocrine side-effects can be indolent and require careful monitoring.

In this single centre audit we looked at the monitoring and rates of development of all patients receiving immune checkpoint inhibitors at the Royal Cornwall Hospital from 2017-2019.


We retrospectively reviewed all patients who received immune check point inhibitors either as single agents or in combination from 2017 to 2019 using the following standards for analysis (these standards were devised after discussion with Endocrine and Oncology consultants)

  1. Baseline cortisol and thyroid stimulating hormone (TSH) to be checked for all patients prior to treatment.
  2. Checking TSH and cortisol every cycle / monthly from the point of initiation of treatment up to 3 months after completion for all patients.

         Data sources included outpatient clinic letters, electronic prescriptions, biochemistry results and multidisciplinary team meeting summaries. Analysis of quantitative data was in percentages and proportions.


A total of 276 patients received 2485 cycles of treatment with immune checkpoint inhibitors for various tumour types between January 2017 and January 2019 at RCHT. Of these 56 patients or 20.2% developed biochemically defined endocrinopathy which is slightly higher than anticipated as per other reports in literature. Only 50 % of patients were symptomatic. The most predominant endocrine dysfunction was thyroiditis and a secondary analysis of agent specific rates was also performed. This audit has led to implementation of change locally to improve local monitoring guidelines.


20.2% of patients developed endocrine dysfunction and there was inconsistent monitoring of endocrine function. This supports the need for a monitoring protocol for all patients starting immunotherapy to assess for endocrine dysfunction, as they could be potentially life threatening.