What is the prognostic impact of FDG PET in locally advanced head and neck squamous cell carcinoma treated with concomitant chemo-radiotherapy? A systematic review and meta-analysis.

PURPOSE: Evidence is conflicting on the prognostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in head and neck squamous cell carcinoma. The aim of our study was to determine the impact of semiquantitative and qualitative metabolic parameters on the outcome in patients managed with standard treatment for locally advanced disease. METHODS: A systematic review of the literature was conducted. A meta-analysis was performed of studies providing estimates of relative risk (RR) for the association between semiquantitative metabolic parameters and efficacy outcome measures. RESULTS: The analysis included 25 studies, for a total of 2,223 subjects. The most frequent primary tumour site was the oropharynx (1,150/2,223 patients, 51.7%). According to the available data, the majority of patients had stage III/IV disease (1,709/1,799, 94.9%; no information available in four studies) and were treated with standard concurrent chemoradiotherapy (1,562/2,009 patients, 77.7%; only one study without available information). A total of 11, 8 and 4 independent studies provided RR estimates for the association between baseline FDG PET metrics and overall survival (OS), progression-free survival (PFS) and locoregional control (LRC), respectively. High pretreatment metabolic tumour volume (MTV) was significantly associated with a worse OS (summary RR 1.86, 95% CI 1.08-3.21), PFS (summary RR 1.81, 95% CI 1.14-2.89) and LRC (summary RR 3.49, 95% CI 1.65-7.35). Given the large heterogeneity (I2 > 50%) affecting the summary measures, no cumulative threshold for an unfavourable prognosis could be defined. No statistically significant association was found between SUVmax and any of the outcome measures. CONCLUSION: FDG PET has prognostic relevance in the context of locally advanced head and neck squamous cell carcinoma. Pretreatment MTV is the only metabolic variable with a significant impact on patient outcome. Because of the heterogeneity and the lack of standardized methodology, no definitive conclusions on optimal cut-off values can be drawn.

Benefit of ablative versus palliative-only radiotherapy in combination with nivolumab in patients affected by metastatic kidney and lung cancer.

PURPOSE: Here, we present the results from a retrospective analysis, with the purpose of evaluating the safety and feasibility of nivolumab and radiotherapy (RT) concomitant association in metastatic kidney and lung cancer patients. MATERIALS AND METHODS: From August 2015 until September 2017, we retrospectively observed 20 patients with metastatic lung and renal cell carcinoma who had been initiated therapy with nivolumab and underwent concomitant RT. RT was administered either as an ablative therapy in the oligometastatic/oligoprogressive setting or as palliative-only treatment for symptomatic patients. Data on progression-free and overall survival (PFS and OS), treatment response and adverse events were collected and reported. Comparison between palliative-only and ablative treatments was performed. RESULTS: PFS and OS were 7 and 12.5 months in the entire population, respectively. Oligoprogressive patients treated with ablative intent, compared to patients undergoing RT with palliative-only intent, had statistically longer PFS (11.5 vs 5.2 months, HR 0.42, CI 0.18-0.98, p 0.03) and OS (17.9 vs 10.31 months, HR 0.41 CI 0.16-1.02, p 0.04). Considering only patients treated with ablative intent, 87.5% showed response to treatment, and complete response was reported in 37.5% of cases. Adverse G2-G3 related to combination treatment were reported as follows: 1 gastrointestinal (nausea), 4 breakthrough pain. CONCLUSIONS: Our data showed significant advantage for oligoprogressive patients treated with RT during nivolumab therapy. No safety alert emerged. These results underline the potential synergistic effects of RT and Immune therapy combination. Our analysis prompts further prospective studies exploring the benefit of integrated treatment strategies.