The real world experience of Australian patients with non-melanoma solid tumours receiving anti-PD-1 checkpoint inhibitors appears to reflect clinical trial data.
The findings provide some additional evidence to support patient decision-making around self-funding costly treatments such as pembrolizumab (Keytruda) or nivolumab (Opdivo).
A review of 47 patients at the Peter MacCallum Cancer Centre found those with non-small cell lung cancer, renal carcinoma or triple negative breast cancer plus an ECOG score of 0-1 achieved a partial response from a checkpoint inhibitor.
The median overall survival was 5.7 months and no patients achieved a complete response.
Of the patients who had radiological disease progression at first re-staging, 16 (48%) continued with their treatment and three eventually achieved a radiologic partial response.
Targeted radiotherapy while continuing immunotherapy resulted in a partial response in two patients.
Patients with other cancer types including head and neck, gynaecological and upper gastrointestinal cancers or those with ECOG scores of 2-4 did not respond to the anti-PD-1 inhibitors.
The study said the findings should help improve patient selection and inform counseling regarding self-funding of treatment.
“Deciding whether to continue treatment in the event of disease progression, especially if a patient has the means to self-fund therapy, is an ongoing challenge for clinicians.”
They added “the finding that patients with poor performance status are unlikely to respond to immunotherapy prescribed for advanced, multiple relapsed disease, regardless of tumour type is an important finding for oncologists, given that discussion with patients about unfunded anticancer drugs are now occurring frequently in daily practice.”
The study also found 71% of patients were still receiving some form of anticancer treatment within the last month of their lives and 62% were admitted to hospital including intensive care.
The rate of palliative care referrals for all patients was 70% however only 47% of patients had an advanced care plan in place.