title: Lung cancer staging: a physiological update.
abstract: The tumour-node metastasis (TNM) classification system is anatomically based. We investigated whether the addition of simple physiological variables, age and body mass index (BMI), would affect survival curves, i.e. a composite anatomical and physiological staging system. We retrospectively analysed a prospectively validated thoracic surgery database (n = 1981). Cox multivariate analysis was performed to determine possible significant factors. Kaplan-Meier survival curves were constructed with combined anatomical and physiological factors. Cox multivariate analysis revealed age (P < 0.001) and BMI (P = 0.01) as significant factors affecting survival. Receiver operating curve analysis determined cut-off levels for age of 67 and BMI of 27.6. A composite anatomical and physiological survival curve based on TNM for BMI > 27.6 and age < 67 was produced. Age and BMI criteria resulted in significantly different survival curves, for stage I (P < 0.0001) and stage II (P = 0.0032), but not for stage III (P = 0.06). Neural network analysis confirmed the importance of BMI and age above cancer stage with regard to long-term survival. Combining age < 67, BMI > 27.6 and TNM anatomical classification results in very different estimated survival curves from the usual TNM system. Patients from stages I, II and III may have survival equivalent to a stage higher or lower depending on their age and BMI.
authors.affiliation: Liverpool Heart and Chest Hospital, Liverpool, UK. mike.poullis@lhch.nhs.uk
authors.forename: Michael
authors.initials: M
authors.lastname: Poullis
authors.forename: James
authors.initials: J
authors.lastname: McShane
authors.forename: Mathew
authors.initials: M
authors.lastname: Shaw
authors.forename: Steven
authors.initials: S
authors.lastname: Woolley
authors.forename: Michael
authors.initials: M
authors.lastname: Shackcloth
authors.forename: Richard
authors.initials: R
authors.lastname: Page
authors.forename: Neeraj
authors.initials: N
authors.lastname: Mediratta
mesh_terms: D000367:Age Factors; D000368:Aged; D001706:Biopsy; D015992:Body Mass Index; D004739:England; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging / Q000379:methods*; D016571:Neural Networks, Computer; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome