No compensatory lung growth after resection in a one-year follow-up cohort of patients with lung cancer

Abstract

Background: As compensatory lung growth after lung resection has been studied in animals of various ages and in one case report in a young adult, it has not been studied in a cohort of adults operated for lung cancer.

Methods: A prospective study including patients with lung cancer was conducted over two years. Parenchymal mass was calculated using computed tomography before (M0) and at 3 and 12 months (M3 and M12) after surgery. Respiratory function was estimated by plethysmography and CO/NO lung transfer (D_LCO and D_LNO). Pulmonary capillary blood volume (Vc) and membrane conductance for CO (Dm_CO) were calculated. Insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) plasma concentrations were measured simultaneously.

Results: Forty-nine patients underwent a pneumonectomy (N=12) or a lobectomy (N=37) thirty two completed the protocol. Among all patients, from M3 to M12 the masses of the operated lungs (239±58 to 238±72 g in the lobectomy group) and of the non-operated lungs (393±84 to 377±68 g) did not change. Adjusted by the alveolar volume (V_A), D_LNO/V_A decreased transiently by 7% at M3, returning towards the M0 value at M12. Both Vc and Dm_CO increased slightly between M3 and M12. IGF-1 and IGFBP-3 concentrations did not change at M3, IGF-1 decreased significantly from M3 to M12.

Conclusions: Compensatory lung growth did not occur over one year after lung surgery. The lung function data could suggest a slight recruitment or distension of capillaries owing to the likely hemodynamic alterations. An angiogenesis process is unlikely.

Keywords: Lung resection; cancer; lung growth; lung mass (mL); pulmonary diffusion.

Figure 1

Screening and inclusion in the protocol.

Figure 2

Mass difference of the non-operated lung between M3 and M12 as a function of the initial reading at M3. Masses are reported in grams. The linear regression equation is: y = ‒0.354x + 123, r²=0.35 (n=32).