Coverage of Lateral Lymph Nodes in Rectal Cancer Patients with Routine Radiation Therapy Practice and Associated Locoregional Recurrence Rates.

PURPOSE: Involved internal iliac and obturator lateral lymph nodes (LLNs) are a known risk factor for the occurrence of ipsilateral local recurrences (LLR) in rectal cancer. This study examined coverage of LLNs with routine radiation therapy practice in the Netherlands and associated LLR rates. METHODS AND MATERIALS: Patients with a primary tumor ≤8 cm of the anorectal junction, cT3-4 stage, and at least 1 internal iliac or obturator LLN with short axis ≥5 mm who received neoadjuvant (chemo)radiation therapy, were selected from a national, cross-sectional study of patients with rectal cancer treated in the Netherlands in 2016. Magnetic resonance images and radiation therapy treatment plans were reviewed regarding segmented LLNs as gross tumor volume (GTV), location of LLNs within clinical target volume (CTV), and received proportion of the planned radiation therapy dose. RESULTS: A total of 223 out of 3057 patients with at least 1 LLN ≥5 mm were selected. Of those, 180 (80.7%) LLNs were inside the CTV, of which 60 (33.3%) were segmented as GTV. Overall, 202 LLNs (90.6%) received ≥95% of the planned dose. Four-year LLR rates were not significantly higher for LLNs situated outside the CTV compared with those inside (4.0% vs 12.5%, P = .092) or when receiving <95% versus ≥95% of the planned radiation therapy dose (7.1% vs 11.3%, P = .843), respectively. Two of 7 patients who received a dose escalation of 60 Gy developed an LLR (4-year LLR rate of 28.6%). CONCLUSIONS: This evaluation of routine radiation therapy practice showed that adequate coverage of LLNs was still associated with considerable 4-year LLR rates. Techniques resulting in better local control for patients with involved LLNs need to be explored further.

FGFR4 Is a Potential Predictive Biomarker in Oral and Oropharyngeal Squamous Cell Carcinoma.

OBJECTIVE: The aim of this study was to investigate whether fibroblast growth factor receptor 4 (FGFR4) could serve as a potential therapeutic target, prognostic biomarker or biomarker predicting radiotherapy sensitivity in oral squamous cell carcinoma (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC). METHODS: FGFR4 immunohistochemistry and FGFR4/CEN5q FISH were performed on tissue microarrays from 212 OSCC and 238 OPSCC patients. FGFR4 genotypes were determined by PCR and DNA sequencing in 76 random OPSCC samples. The response to radiotherapy was evaluated 3 months after the last radiotherapy treatment session by a head and neck radiation oncologist and/or surgeon during clinic visits. The results were correlated to overall survival and response to radiotherapy. RESULTS: The FGFR4 protein was overexpressed in 64% (153/238) of OPSCCs and 41% (87/212) of OSCCs. The FGFR4 gene was amplified in 0.47% (1/212) of OSCCs and 0.42% (1/238) of OPSCCs, and the FGFR4 Gly388Arg polymorphism was detected in 62% (47/76) of OPSCCs. FGFR4 protein expression, FGFR4 gene copy numbers and FGFR4 genotypes were not related to overall survival or response to radiotherapy in OSCC or OPSCC. CONCLUSION: FGFR4 is frequently overexpressed in OSCC and OPSCC in the absence of gene amplification, and may serve as a potential predictive marker for FGFR4-directed targeted therapy in OSCC and OPSCC.

The importance of actual tumor growth rate on disease free survival and overall survival in laryngeal squamous cell carcinoma.

BACKGROUND AND PURPOSE: Evaluation of the variation in tumor growth rate and the influence of tumor growth rate on disease free survival (DFS) and overall survival (OS) in laryngeal squamous cell carcinoma (LSCC). MATERIAL AND METHODS: We delineated tumor volume on a diagnostic and planning CT scan in 131 patients with laryngeal squamous cell carcinoma and calculated the tumor growth rate. Primary endpoint was DFS. Follow up data were collected retrospectively. RESULTS: A large variation in tumor growth rate was seen. When dichotomized with a cut-off point of -0.3 ln(cc/day), we found a significant association between high growth rate and worse DFS (p = 0.008) and OS (p = 0.013). After stepwise adjustment for potential confounders (age, differentiation and tumor volume) this significant association persisted. However, after adjustment of N-stage association disappeared. Exploratory analyses suggested a strong association between N-stage and tumor growth rate. CONCLUSIONS: In laryngeal squamous cell carcinoma, there is a large variation in tumor growth rate. This tumor growth rate seems to be an important factor in disease free survival and OS. This tumor growth rate is independent of age, differentiation and tumor volume associated with DFS, but N-stage seems to be a more important risk factor.

Computed tomography-based tumour volume as a predictor of outcome in laryngeal cancer: results of the phase 3 ARCON trial.

PURPOSE: Retrospective studies indicate that larger tumour volume is a strong prognostic indicator for poor tumour control after (chemo)radiotherapy for laryngeal cancer. The impact of tumour volume on the outcome of patients treated within a prospective study comparing accelerated radiotherapy (AR)±carbogen breathing and nicotinamide (ARCON) was investigated. METHODS AND MATERIALS: Of 345 patients with cT2-4 laryngeal cancer, pre-treatment computed tomography (CT) scans of 270 patients were available for tumour volume calculation. Contouring of the primary tumour and involved lymph nodes was reviewed by one experienced head and neck radiation oncologist. Kaplan-Meier plots were used for analysis of outcome. RESULTS: Of 137 AR and 133 ARCON patients, 57 and 80 versus 56 and 77 patients had glottic and supraglottic tumours, respectively. A correlation between primary tumour volume and T-stage was observed (Rs=.51, P<.01). In both treatment arms no correlation was detected between the primary tumour volume and local control (LC), regional control (RC) and metastasis-free survival (MFS). A strong correlation between total nodal volume and N-stage was found (Rs=.93, P<.01). Both in the AR and ARCON groups total nodal volume was not associated with poorer RC rate. However, based on individual lymph node analyses, nodal control was in favour of ARCON, irrespective of volume (P<.01). CONCLUSION: Neither primary tumour volume, nor total nodal volume is a prognostic factor for patients with cT2-4 laryngeal cancer treated with accelerated radiotherapy±carbogen breathing and nicotinamide. Additional analyses based on individual nodal volumes demonstrate an excellent regional control rate and a significant benefit of ARCON.