Background The National Lung Cancer Audit routinely reports to each unit the percentage of their patients who have received histological confirmation of a diagnosis of lung cancer. This could therefore be interpreted as a key performance indicator for a cancer unit. We studied the factors that influenced the rate of histological confirmation of diagnosis in our population.
Methods Data were extracted from our existing lung cancer database from January 2009 to May 2011. Demographics and clinical data were analysed to assess the factors that led to failure of confirmation of histological diagnosis.
Results Out of 907 patients with lung cancer, 183 (20%) did not have a histological diagnosis. Based on TNM staging, 10% had stage I, 5% stage II, 19% stage III and 50% stage IV disease. Co-morbidities were significant in this group—57% had severe COPD, 12% had IHD and 11% had had a previous CVA. Of the 183 patients identified, 49 (27%) had at least one attempt at obtaining histology that proved to be non-diagnostic, either bronchoscopy (46 pts) or other procedure (3 pts). 41 (22%) were actively treated—6 (15%) had radical treatment, 5 (12%) had palliative chemotherapy and 29 (70%) had palliative radiotherapy. Performance status (PS) and co-morbidities were the main factors affecting decision to obtain histology. As the Abstract P163 table 1 suggests, patients without histology tended to be older (p<0.0008) and a greater proportion had a PS of three or more.
Conclusion These data suggest that patients who do not ultimately receive histological confirmation of a diagnosis of lung cancer are a heterogenous population. In most cases the factors that influenced the failure to obtain histology were poor performance status and co-morbidities. We conclude that the percentage of lung patients without histological confirmation of diagnosis may ultimately reflect the overall health of the local population rather than the specific quality of a lung cancer unit's clinical practice. As such we would advocate caution when interpreting differences in this parameter between units.