ecancermedicalscience

Research

Utility of PET-CT in non-small cell lung cancer clinical stage IB-IIA according to AJCC 8th edition staging system: an alternative to invasive mediastinal staging?

15 Jun 2021
Agustin Buero, Domingo J Chimondeguy, Rodolfo Auvieux, Gustavo A Lyons, Leonardo G Pankl, Guillermo Puchulo, Silvia Quadrelli

Objective: Mediastinal nodal staging in lung cancer is essential to determine treatment strategy and prognosis. There are controversies as to whether a mediastinal negative result in PET-CT may spare the invasive staging of the mediastinum. The main endpoint is to evaluate the negative predictive value (NPV) of PET-CT in non-small cell lung cancer (NSCLC) clinical stage IB-IIA without clinical nodal involvement. The secondary endpoint is to evaluate the prevalence of mediastinal and hilar nodal affection in this population.

Methods: We performed an observational descriptive study from January 2010 to January 2020, including 76 patients with clinical stage IB-IIA, who underwent pulmonary resection with systematic nodal sampling (pre-determined lymph node stations based on tumour location) for primary NSCLC. Clinically, nodal involvement was defined as any lymph node greater than 1 cm in the short axis on a CT or with metabolic uptake greater than 2.5 SUV on PET-CT. The prevalence of nodal metastases was recorded.

Results: Fifty six patients had clinical stage IB and 20 had clinical stage IIA. Mean tumour size was 3.74 ± 0.5 cm. Lobectomy was the resection procedure most frequently performed. Of the 76 patients with clinical N0 by PET-CT who underwent surgical resection, 10 (13.1%) were upstaged to pN1 and none were upstaged to pN2. NPV of PET-CT for overall nodal metastasis was 87% (95% CI: 0.79–0.94). NPV of PET-CT for N2 metastasis was 100%.

Conclusion: PET-CT might be an alternative to invasive mediastinal staging in patients with NSCLC clinical stage IB-IIA who are surgical candidates. Further prospective multi-institutional studies are necessary to verify the external validity of our study.

Related Articles

Hemanth Raj, Marri Sri Santosh Keerthi, Ravisankar Palaniappan, Ujwala Prakash, Manikandan Dhanushkodi, Trivadi S Ganesan
Eduardo Payet, Joan Perez, Gustavo Sarria, Silvia Neciosup, Francisco Berrospi, Sheila Vilchez, Jorge Dunstan, Ronald Perez, Mauricio Vassallo, Santiago Salgado, Nanto Caparachín, Joseph A Pinto, Alexis Holguin