Case Report: Madam Tan, a 71-year-old Malaysian Chinese lady, otherwise healthy, presented to her local GP with a complaint of a nodule over the left cheek that had been there for more than a decade. Her concern was that the lesion was growing and had become conspicuous. She had spent most of her life as a farmer working in her orchard.Upon examination, she had an obvious dome-shaped nodule over the left cheek measuring approximately 1.8 cm in diameter. The lesion was firm, pigmented, well-demarcated, and slightly ulcerated at the top. Clinically, she was diagnosed with a pigmented nodular basal cell carcinoma of the left cheek. Examination of the systems was unremarkable.She requested that the consulting GP remove the growth. The cost for specialist treatment and waiting time at the local hospital were her concerns.
Clinical Questions: Can the basal cell skin cancer be excised safely and effectively in the local primary care setting? What are the crucial preoperative concerns?
METHODS: This cross-sectional study was conducted at Hospital Tuanku Fauziah, Perlis, Malaysia from August 2015 to April 2016. FEV1/FEV6 and FEV1/FVC results of 117 subjects were analysed. Demographic data and spirometric variables were tabulated. A scatter plot graph with Spearman's correlation was constructed for the correlation between FEV1/FEV6 and FEV1/FVC. The sensitivity, specificity, positive and negative predictive values of FEV1/FEV6 were determined with reference to the gold standard of FEV1/FVC ratio <0.70. Receiver-operator characteristic (ROC) curve analysis and Kappa statistics were used to determine the FEV1/FEV6 ratio in predicting an FEV1/FVC ratio <0.70.
RESULTS: Spearman's correlation with r = 0.636 (P<0.001) was demonstrated. The area under the ROC curve was 0.862 (95% confidence interval [CI]: 0.779 - 0.944, P<0.001). The FEV1/FEV6 cut-off with the greatest sum of sensitivity and specificity was 0.75. FEV1/FEV6 sensitivity, specificity, positive and negative predictive values were 93.02%, 67.74%, 88.89% and 77.78% respectively. There was substantial agreement between the two diagnostic cut-offs (κ = 0.634; 95% CI: 0.471 - 0.797, P<0.001) CONCLUSIONS: The FEV1/FEV6 ratio can be considered to be a good alternative to the FEV1/FVC ratio for screening of COPD. Larger multicentre study and better education on spirometric techniques can validate similar study outcome and establish reference values appropriate to the population being studied.