Effect of PET/CT standardized uptake values on complete response to treatment before definitive chemoradiotherapy in stage III non-small cell lung cancer

Clin Transl Oncol. 2019 Apr;21(4):499-504. doi: 10.1007/s12094-018-1949-6. Epub 2018 Sep 18.

Abstract

Purpose: The standard treatment for patients with stage III non-small cell lung cancer (NSCLC), unsuitable for resection and with good performance, is definitive radiotherapy with cisplatin-based chemotherapy. Our aim is to evaluate the effect of the maximum value of standardized uptake values (SUVmax) of the primary tumor in positron emission tomography-computed tomography (PET/CT) before treatment on complete response (CR) and overall survival.

Methods: The data of 73 stage III NSCLC patients treated with concurrent definitive chemoradiotherapy (CRT) between 2008 and 2017 and had PET/CT staging in the pretreatment period were evaluated. ROC curve analysis was performed to determine the ideal cut-off value of pretreatment SUVmax to predict CR.

Results: Median age was 58 years (range 27-83 years) and 66 patients were male (90.4%). Median follow-up time was 18 months (range 3-98 months); median survival was 23 months. 1-year overall survival (OS) rate and 5-year OS rate were 72 and 19%, respectively. Median progression-free survival (PFS) was 9 months; 1-year PFS rate and 5-year PFS rate were 38 and 19%, respectively. The ideal cut-off value of pretreatment SUVmax that predicted the complete response of CRT was 12 in the ROC analysis [AUC 0.699 (0.550-0.833)/P < 0.01] with a sensitivity of 83%, and specificity of 55%. In patients with SUVmax < 12, CR rate was 60%, while, in patients with SUV ≥ 12, it was only 19% (P = 0.002). Median OS was 26 months in patients with pretreatment SUVmax < 12, and 21 months in patients with SUVmax ≥ 12 (HR = 2.93; 95% CI 17.24-28.75; P = 0.087). CR rate of the whole patient population was 26%, and it was the only factor that showed a significant benefit on survival in both univariate and multivariate analyses.

Conclusion: Pretreatment SUVmax of the primary tumor in PET/CT may predict CR in stage III NSCLC patients who were treated with definitive CRT. Having clinical CR is the only positive predictive factor for prolonged survival.

Keywords: Chemoradiotherapy; Non-small cell lung cancer; PET/CT; SUVmax; Stage III.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Non-Small-Cell Lung / diagnostic imaging
  • Carcinoma, Non-Small-Cell Lung / metabolism*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Carcinoma, Non-Small-Cell Lung / radiotherapy*
  • Chemoradiotherapy
  • Female
  • Fluorodeoxyglucose F18 / pharmacokinetics
  • Humans
  • Lung Neoplasms / diagnostic imaging
  • Lung Neoplasms / metabolism*
  • Lung Neoplasms / pathology
  • Lung Neoplasms / radiotherapy*
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Positron Emission Tomography Computed Tomography
  • Prognosis
  • ROC Curve
  • Radiopharmaceuticals / pharmacokinetics
  • Retrospective Studies
  • Survival Rate
  • Treatment Outcome

Substances

  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18