BACKGROUND: Insulin-like growth factor 1 (IGF-I), IGF binding proteins (IGFBP) 1 to 7, and C-peptide have been postulated to predict survival in non-small cell lung cancer (NSCLC). Studying serum levels in NSCLC patients treated with surgical resection may provide information on the aggressiveness of tumors and be predictive of disease recurrence.
METHODS: Immunobead assays were used to measure pretreatment serum levels of IGF-I, IGFBP1 to IGFBP7, and C-peptide in 100 NSCLC patients. Of these, 59 had no metastatic progression (T1 to T4 N0 M0), whereas 41 had positive lymph nodes (T1 to T4 N1 to N3 M0). Data were analyzed using the Mann-Whitney two-sided rank sum test or Kaplan-Meier curves.
RESULTS: Low serum IGFBP5 levels correlated strongly with a positive nodal status (p < 0.001) and any incidence of disease recurrence (p = 0.003). Low serum levels of IGFBP5 also predicted poor recurrence-free survivals in the overall cohort (p ≤ 0.001) and in patients with no nodal metastases (p = 0.027). Conversely, a high serum level of IGFBP7 correlated with positive nodal status (p = 0.008), but was not prognostic for recurrence-free survival. No significant correlations were found for IGFBP5 or IGFBP7 for sex, age, race, smoking history, tumor histology, or fasting state.
CONCLUSIONS: IGFBP5 and IGFBP7 had value as biomarkers for identifying NSCLC progression and patient outcome.
BACKGROUND: Lobectomy is considered the standard treatment for early-stage non-small cell lung cancer (NSCLC); however, more limited resections are commonly performed. We examined patient and surgeon factors associated with limited resection and compared postoperative and long-term outcomes between sublobar and lobar resections.
METHODS: A population- and health system-based sample of patients newly diagnosed with stage I or II NSCLC between 2003 and 2005 in five geographically defined regions, five integrated health-care delivery systems, and 15 Veterans Affairs hospitals was observed for a median of 55 months, through May 31, 2010. Predictors of limited resection and postoperative outcomes were compared using unadjusted and propensity score-weighted analyses. All P values are from two-sided tests.
RESULTS: One hundred fifty-five (23%) patients underwent limited resection and 524 (77%) underwent lobectomy. In adjusted analyses of patient-specific factors, smaller tumor size (P = .004), coverage by Medicare or Medicaid, no insurance or unknown insurance (P = .02), more severe lung disease (P < .001), and a history of stroke (P = .049) were associated with receipt of limited resection. In adjusted analyses of surgeon characteristics, thoracic surgery specialty (P = .02), non-fee-for-service compensation (P = .008), and National Cancer Institute cancer center designation (P = .006) were associated with higher odds of limited resection. Unadjusted 30-day mortality was higher with limited resection than with lobectomy (7.1% vs 1.9%, difference = 5.2%, 95% confidence interval [CI] = 1.5% to 10.8%, P = .003), and the adjusted difference was not statistically significant (6.5% vs 2.9%, difference = 3.6%, 95% CI = -.1% to 9.2%, P = .09). Postoperative complications did not differ by type of surgery (all P > .05). Over the course of the study, a non-statistically significant trend toward improved long-term survival was evident for lobectomy, compared with limited resection, in adjusted analyses (hazard ratio of death = 1.35 for limited resection, 95% CI = 0.99 to 1.84, P = .05).
CONCLUSIONS: Evidence is statistically inconclusive but suggestive that lobectomy, compared with limited resection, is associated with increased long-term survival for early-stage lung cancer. Clinical, socioeconomic, and surgeon factors appear to be associated with the choice of surgical resection.