Predictors of toxicity after curative reirradiation with intensity modulated radiotherapy or proton therapy for recurrent head and neck carcinoma: new dose constraints for pharyngeal constrictors muscles and oral cavity.

BACKGROUND: Our study aims to identify predictive factors of moderate to severe (grade ≥ 2) late toxicity after reirradiation (reRT) of recurrent head and neck carcinoma (HNC) and explore the correlations between dose organs at risk (OAR) and grade ≥ 2 toxicity. MATERIAL AND METHODS: Between 09/2007 and 09/2019, 55 patients were re-irradiated with IMRT or proton therapy with curative intent for advanced HNC. Our study included all patients for whom data from the first and second irradiations were available. Co-variables, including interval to reRT, size of re-irradiated PTV, and dose to OAR, were analyzed as potential predictors for developing moderate to severe long-term toxicity with death as a competing risk. Receiver-operator characteristics (ROC) analysis assessed the association between dose/volume parameters and the risk of toxicity. RESULTS: Twenty-three patients participated in our study. After a median follow-up of 41 months, 65% of the patients experienced grade ≥ 2 late toxicity. The average dose to pharyngeal constrictor muscles (PCM) at the time of reRT showed an association with the risk of grade ≥ 2 dysphagia: AUC = 0.78 (95% CI: 0.53-1), optimal cut-off value = 36.7 Gy (sensitivity 62%/specificity 100%). The average dose to the oral cavity at the time of reRT showed an association with the risk of grade ≥ 2 dysgeusia: AUC = 0.96 (0.89-1), optimal cut-off value = 20.5 Gy (sensitivity 100%/specificity 88%). CONCLUSION: Our analysis depicted an association between the dose to OAR and the risk of developing moderate to severe dysphagia and dysgeusia and proposed new dose constraints for PCM (36.7 Gy) and oral cavity (20.5 Gy).

Curative high-dose reirradiation for patients with recurrent head and neck squamous cell carcinoma using IMRT or proton therapy: Outcomes and analysis of patterns of failure.

PURPOSE: To analyze outcomes of patients treated with curative reirradiation (reRT), with intensity-modulated radiation therapy (IMRT) or proton therapy (PT) for recurrent head and neck squamous cell carcinoma (HNSCC). MATERIALS: Among the 55 patients reirradiated for head and neck cancer from 30/08/2012 to 08/04/2019, 23 had HNSCC and received IMRT (52.2%) or PT (47.8%) at a median maximum dose to the CTV of 66 Gy. RESULTS: After a median follow-up of 41.3 months, 18 patients developed a locoregional recurrence (LR), of which eight (44.4%) occurred within the previously reirradiated volume. Two-year locoregional failure-free survival and overall survival were 18.3%[95%CI:7.1%-47.1%] and 42.5%[95%CI:26.2%-69.1%], respectively. Disease-free survival was significantly longer in the PT group (p = 0.031). Main late grade ≥2 toxicities were dysphagia and trismus. CONCLUSION: Curative reRT in HNSCC is possible for selected cases, but the LR rate in the irradiated field and the risk of toxicity grade ≥2 remain high.

Biomarkers of cetuximab resistance in patients with head and neck squamous cell carcinoma.

Objective: In patients with head and neck squamous cell carcinoma (HNSCC), cetuximab [a monoclonal antibody targeting epidermal growth factor receptor (EGFR)] has been shown to improve overall survival when combined with radiotherapy in the locally advanced setting or with chemotherapy in first-line recurrent and/or metastatic (R/M) setting, respectively. While biomarkers of resistance to cetuximab have been identified in metastatic colorectal cancer, no biomarkers of efficacy have been identified in HNSCC. Here, we aimed to identify biomarkers of cetuximab sensitivity/resistance in HNSCC. Methods: HNSCC patients treated with cetuximab at the Curie Institute, for whom complete clinicopathological data and formalin-fixed paraffin-embedded (FFPE) tumor tissue collected before cetuximab treatment were available, were included. Immunohistochemistry analyses of PTEN and EGFR were performed to assess protein expression levels. PIK3CA and H/N/KRAS mutations were analyzed using high-resolution melting (HRM) and Sanger sequencing. We evaluated the predictive value of these alterations in terms of progression-free survival (PFS). Results: Hot spot activating PIK3CA and KRAS/HRAS mutations were associated with poor PFS among HNSCC patients treated with cetuximab in the first-line R/M setting, but not among HNSCC patients treated with cetuximab in combination with radiotherapy. Loss of PTEN protein expression had a negative predictive value among HNSCC patients treated with cetuximab and radiotherapy. High EGFR expression did not predict cetuximab sensitivity in our patient population. Conclusions: Hot spot activating PIK3CA and RAS mutations predicted cetuximab resistance among HNSCC patients in the first-line R/M setting, whereas loss of PTEN protein expression predicted resistance to cetuximab when combined to radiotherapy.

Immune gene expression in head and neck squamous cell carcinoma patients.

BACKGROUND: Nivolumab and pembrolizumab targeting programmed cell death protein 1 (PD-1) have recently been approved among patients with recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) who failed platinum therapy. We aimed to evaluate the prognostic value of selected immune gene expression in HNSCC. PATIENTS AND METHODS: We retrospectively assessed the expression of 46 immune-related genes and immune-cell subpopulation genes including immune checkpoints by real-time polymerase chain reaction among 96 patients with HNSCC who underwent primary surgery at Institut Curie between 1990 and 2006. Univariate and multivariate analyses were performed to assess the prognostic value of dysregulated genes. RESULTS: The Median age of the population was 56 years [range: 35-78]. Primary tumour location was oral cavity (45%), oropharynx (21%), larynx (18%) and hypopharynx (17%). Twelve patients (13%) had an oropharyngeal human papillomavirus-positive tumour. Most significantly overexpressed immune-related genes were TNFRSF9/4-1BB (77%), IDO1 (75%), TNFSF4/OX40L (74%) and TNFRSF18/GITR (74%), and immune-cell subpopulation gene was FOXP3 (62%). Eighty-five percent of tumours analysed overexpressed actionable immunity genes, including PD-1/PD-L1, TIGIT, OX40/OX40L and/or CTLA4. Among the immune-related genes, high OX40L mRNA level (p = 0.0009) and low PD-1 mRNA level (p = 0.004) were associated with the highest risk of recurrence. Among the immune-cell subpopulation genes, patients with high PDGFRB mRNA level (p < 0.0001) and low CD3E (p = 0.0009) or CD8A mRNA levels (p = 0.004) were also at the highest risk of recurrence. CONCLUSIONS: OX40L and PDGFRB overexpression was associated with poor outcomes, whereas PD-1 overexpression was associated with good prognosis in patients with HNSCC treated with primary surgery, suggesting their relevance as potential prognostic biomarkers and major therapeutic targets.

Use of Metabolic Parameters as Prognostic Factors During Concomitant Chemoradiotherapy for Locally Advanced Cervical Cancer.

OBJECTIVES: To investigate the use of metabolic parameters as early prognostic factors during concomitant chemoradiotherapy for locally advanced cervix carcinoma (LACC). MATERIALS AND METHODS: Between February 2008 and January 2012, 34 consecutive patients treated for LACC (International Federation of Gynecology and Obstetrics Staging System stage IB2-IVA) were included in a retrospective study. Treatment was standard of care: total dose of 45 Gy in 1.8 Gy per fraction with concurrent cisplatin followed by brachytherapy. 18F-FDG PET-CT modalities were performed before treatment and per-treatment (at 40 Gy). The analyzed parameters were: maximum standardized uptake value (SUVmax), SUVmax variations of the primary tumor between the 2 investigations (DSUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Survival was assessed according to early metabolic changes during chemoradiotherapy. RESULTS: Median follow-up was 16 months (range, 5.3 to 32.4 mo). Median SUVmax before treatment was 13.15 (5.9 to 31) and was 5.05 (0 to 12) per-treatment. Median DSUVmax was 63.97% (0% to 100%). Median MTV before treatment was 44.16 mL (3.392 to 252.768 mL) and was 5.44 mL (0 to 69.88 mL) per-treatment. Median TLG before treatment was 249.82 mL (13.40 to 1931.10 mL) and was 20.14 mL (0 to 349.99 mL) per-treatment. At 40 Gy, SUVmax≥6, DSUVmax≤40%, MTV≥5.6 mL, and TLG≥21.6 mL were significantly associated with overall survival and progression-free survival reduction. MTV predicted progression with a sensitivity of 80% and a specificity of 87.5% and TLG with a sensitivity of 80% and a specificity of 83.3%. CONCLUSIONS: PET-CT imaging could be useful as an early prognostic factor during treatment for LACC. MTV and TLG seem to provide better prognostic information than SUVmax and DSUVmax.

Stereotactic ablative radiotherapy for early stage non-small cell lung cancer: A critical literature review of predictive factors of relapse.

Stereotactic ablative radiation therapy (SABR) has become the standard treatment for peripheral medically non-operable patients with early stage non-small cell lung cancer (NSCLC). Previous attempts of trials to compare SABR and surgery have failed and new randomized studies (SABRtooth, STABLEMATES, and VALOR) are ongoing. While predictive factors of relapse have been extensively studied in patients receiving surgery, there is scarce data on such putative factors in SABR patients. The purpose of this review is to analyze such predictive factors through a critical review of the literature.

Early assessment of metabolic response by 18F-FDG PET during concomitant radiochemotherapy of non-small cell lung carcinoma is associated with survival: a retrospective single-center study.

BACKGROUND AND PURPOSE: We performed a retrospective single-center study to assess if midtreatment 18F-FDG PET/CT could predict local control and survival in patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy. METHODS: Thirty-one consecutive patients with unresectable or locally advanced lung cancer (T2-4 N0-3 M0) were treated with concurrent chemoradiotherapy in our center. Each patient received 18F-FDG PET/CT before treatment and at midtreatment time when a radiation therapy dose of 30 Gy was delivered. We assessed several PET/CT parameters as follows: SUV max, ΔSUV mean, ΔSUV max, variation of hypermetabolic tumor volume, and the variation of tumor total lesion glycolysis (ΔTLG). Univariate analysis was performed, and a stepwise procedure was used to define final multivariate model. RESULTS: The ΔTLG was statistically correlated to overall survival (OS) (P = 0.035), progression-free survival (P = 0.023), and local control (P = 0.043) in univariate analysis. A decrease in TLG over 15% was statistically correlated to a better OS (P = 0.007; hazards ratio [HR], 7.439; 95% confidence interval [CI], 1.168-28.897) and progression-free survival (P = 0.010; HR, 5.695; 95% CI, 1.506-21.537) in univariate analysis. In multivariate analysis, ΔTLG superior to -15% was significantly correlated to a worse OS (P = 0.020; HR, 5.973; 95% CI, 1.324-26.953). CONCLUSIONS: Early assessment of TLG response by 18F-FDG PET/CT during concomitant radiochemotherapy of non-small cell lung cancer might be associated with survival.