Measuring toxicity following systemic therapy for lung cancer in Aotearoa New Zealand using a cancer-specific framework and national collections data.

AIM: Toxicities are a common side effect of systemic therapy delivered to treat lung cancer. In this study, we have applied a cancer-specific toxicity coding framework and national-level data to describe the number and types of severe acute toxicities experienced by patients receiving systemic therapy for lung cancer in New Zealand. METHODS: Participants included all New Zealanders diagnosed with lung cancer between 2012 and 2019 on the New Zealand Cancer Registry (NZCR; N=18,081). NZCR data were linked to a national pharmaceutical dataset to identify receipt of systemic therapy and then to inpatient hospitalisation data to identify toxicities following this treatment. A cancer-specific toxicity coding framework was used to define toxicities. Descriptive analysis and regression modelling were used to describe the toxicity profile of those undergoing systemic therapy for lung cancer, by tumour type. RESULTS: Using our framework and the available data, we observed that four in every five lung cancer patients receiving systemic therapy experience some toxicity during treatment. Around half of our cohort were diagnosed with an infection of some kind, most commonly lung infection. Other common toxicities included constipation, hypotension, cardiac arrhythmia, anaemia, neutropenia and sepsis. Those with small cell lung cancer were more likely to be diagnosed with neutropenia, sepsis and electrolyte disturbances than those with other tumour types. CONCLUSION: We observed a significant toxicity burden using administrative health records and a cancer-specific toxicity coding framework. With the caveats identified and discussed throughout this paper, this system can be used to identify and better understand this burden in other cancer contexts.