Dose-volume relationship for laryngeal substructures and aspiration in patients with locally advanced head-and-neck cancer

Quantitative prediction of aspiration risk in head and neck cancer patients treated with radiation therapy

OBJECTIVE

To determine characteristics most strongly associated with risk for aspiration events among head and neck cancer (HNC) patients undergoing curative intent treatment.

MATERIALS AND METHODS

This was a retrospective, cross-sectional study of 106 patients with previously untreated HNC who received definitive or postoperative radiation therapy (RT) +/- systemic therapy with curative intent. Patients who received post-treatment videofluoroscopic swallow study (VFSS) between 2018-2021 were included. Using ordinal multivariable logistic regression, we modeled the effects of age (>60 years vs. ≤60 years), sex, body mass index (BMI) (>20 kg/m² vs. ≤20 kg/m²), American Joint Committee on Cancer 8th edition stage (I-II vs. III-IVB), treatment with cisplatin (vs. other or no systemic therapy), post-operative status, primary site (oral cavity vs. P16+ oropharynx vs. P16- Mucosal Site vs. other), and quantitative VFSS measures on Penetration-Aspiration Scale (PAS) score.

RESULTS AND CONCLUSION

On ordinal multivariable logistic regression, age >60 years (odds ratio (OR): 3.91, 95% confidence interval (CI): 1.29, 11.9), advanced stage (stage III-IVB) (OR: 3.13, 95% CI: 1.23, 7.79), pharyngeal constriction ratio (PCR) >0.25 (OR: 3.65, 95% CI: 1.14, 11.7), and bolus clearance ratio (BCR) > 0.10 (OR: 3.42, 95% CI: 1.20, 9.75) were found to be significant risk factors for higher PAS scores. Patients with ≥ 2 pre-treatment risk factors had statistically significant increased risk for post-treatment aspiration (OR 2.52, 95% CI: 1.31, 4.86) on ordinal logistic regression. This model could be useful to direct high-risk patients toward interventions designed to reduce risk of aspiration events.

Investigation of the Effect of Radiotherapy Dose on Chewing and Swallowing Structures in Head and Neck Cancer Patients Treated with Concomitant Chemoradiotherapy

Intensity-modulated radiotherapy (IMRT) is a treatment method that is used in the treatment of head and neck cancers. Impairment of chewing and swallowing functions in the early and late periods of radiotherapy is frequent. Therefore, revealing the dose-effect relationship is important. The main purpose of this study is to investigate the dose-effect relationship between chewing and swallowing structures objectively via a standardized videofluoroscopy protocol. The study included 35 participants treated with chemo-IMRT. A videofluoroscopic swallowing study (VFSS) was performed before IMRT, and 3 and 6 months after IMRT. VFSS results were scored according to the Modified Barium Swallow Impairment Profile (MBSImP) and the Penetration-Aspiration Scale (PAS). Maximum interincisor mouth opening, body mass index (BMI), and Functional Oral Intake Scale levels were determined in these cases. The quality of life of participants was evaluated. There was a significant increase in PAS and MBSImP scores and a significant decrease in BMI scores of the patients after treatment. Xerotomy and sticky saliva complaints increased after treatment. The dose to the mastication muscles (> 40 Gy) and the temporomandibular joint (> 46 Gy) were found to be associated with a decrease in BMI; the dose to the superior pharyngeal constructor muscle (> 58 Gy) was found to be associated with pharyngeal stripping wave. The presence of aspiration was associated with the inferior pharyngeal constructor muscle, glottic larynx, supraglottic larynx, and upper esophageal sphincter. Important findings to emerge from this study include detected toxic dose limits. These findings may guide physicians to minimize the side effects of IMRT.

Early-Stage Glottic Squamous Cell Carcinoma in the Era of Image-Guided Radiotherapy

Early-stage squamous cell cancer (SCC) of the glottis has a good prognosis. Therefore, patients have long survival outcomes and may potentially suffer from late toxicities of radiotherapy. Radiotherapy with a conventional parallel-opposed-pair or anterior-oblique beam arrangements for stage 1 and 2 glottic SCC have field borders that traditionally cover the entire larynx, exposing organs-at-risk (e.g. carotid arteries, contralateral vocal cord, contralateral arytenoid and inferior pharyngeal constrictor muscles) to high radiation doses. The potential long-term risk of cerebrovascular events has attracted much attention to the dose that carotid arteries receive. Swallow and respiratory motion of laryngeal structures has been an important factor that previously limited reduction of the radiation treatment volume. Motion has been evaluated using multiple imaging modalities and this information has been used to calculate PTV margins for generation of more limited target volumes. This review discusses the current literature surrounding dose-effect relationships for various organs-at-risk and the late toxicities that are associated with them. This article also reviews the currently available data and effects of laryngeal motions on dosimetry to the primary target. We also review the current limitations and benefits of a more targeted approach of radiotherapy for early-stage glottic SCCs and the evolution of CT-based IGRT and MR-guided radiotherapy techniques that may facilitate a shift away from a conventional 3D-conformal radiotherapy approach.

Late toxicities in locally advanced head and neck squamous cell carcinoma treated with intensity modulated radiation therapy

Purpose

The study aims to report late toxicities in locally advanced head-and-neck squamous cell carcinoma (LAHNSCC) treated with intensity-modulated radiation therapy (IMRT).

Materials and Methods

A retrospective study was conducted on 103 patients of LAHNSCC treated with IMRT. We analyzed the cumulative incidence of late xerostomia, dysphagia, and aspiration at an interval of 6-month, 1-year, 2-year, and 3-year from the start of IMRT.

Results

At a median follow up of 4.2 years (interquartile range, 3.5 to 6 years), the cumulative incidence of grade ≥2 late xerostomia was 5.5%, dysphagia was 6.9%, and aspiration was 11.1%. Logistic regression showed that D_mean of ≥26 Gy to parotids had higher risk of xerostomia (hazard ratio [HR] = 5.19; 95% confidence interval [CI], 1.90–14.22; p = 0.001). Late dysphagia was associated with D_mean of ≥45 Gy to pharyngeal constrictors (PC) (HR = 7; 95% CI, 1.84–26.61; p =0.004), ≥55 Gy to larynx (HR = 3.25; 95% CI, 1.15–9.11; p = 0.025), and adjuvant RT (HR = 5.26; 95% CI, 1.85–14.87; p = 0.002). Aspiration was associated with D_mean of ≥45 Gy to larynx (HR = 6.5; 95% CI, 1.93–21.88; p = 0.003), D_mean of ≥55 Gy to PC (HR = 3.54; 95% CI, 1.25–9.98; p = 0.017), and patients having late dysphagia (HR = 4.37; 95% CI, 1.55–12.31; p = 0.005).

conclusions

IMRT is a feasible radiation delivery technique in LAHNSCC with a decreased late toxicity profile.

Impact of Transoral Radiofrequency Microsurgery and Radiotherapy on Long-term Swallowing Function in Patients with T1 Glottic Carcinoma

To compare the impact of transoral radiofrequency microsurgery (TRM) and radiotherapy (RT) on long-term swallowing function in patients with T1 glottic carcinoma. A total of 41 cases of T1 glottic carcinoma treated with TRM or RT alone more than 5 years ago were collected, including 17 cases treated with TRM (TRM group) and 24 cases treated with RT (RT group). The Chinese version of the Swallowing Quality-of-Life Questionnaire (CSWAL-QOL) and videofluoroscopic swallowing study results at the last follow-up (more than 5 years after TRM or RT) were assessed. The TRM group scored significantly better than the RT group on overall CSWAL-QOL, the Frequency score, and 6 out of 10 CSWAL-QOL dimensions. The RT group scored significantly better than the TRM group only on the Communication dimension. The dysphagia score (DS) and penetration-aspiration scale (PAS) score of the TRM group were better than those of the RT group. The overall CSWAL-QOL score, the Frequency score, DS, and PAS scores were not significantly different between patients who received conventional radiotherapy and patients who received intensity-modulated radiation therapy. The RT dose was correlated with the DS. TRM provides better swallowing outcomes as compared to RT in management of early glottic cancer. In addition, there is a correlation between RT dose and dysphagia. Prospective studies should be conducted to further evaluate the impact of TRM and RT on swallowing function.

NMR-Based Metabolomics in Investigation of the Radiation Induced Changes in Blood Serum of Head and Neck Cancer Patients and Its Correlation with the Tissue Volumes Exposed to the Particulate Doses

In the present study, we analyze the nuclear magnetic resonance (NMR) blood serum metabolic profiles of 106 head and neck squamous cell carcinoma (HNSCC) patients during radio (RT) and concurrent radio-chemotherapy (CHRT). Four different fractionation schemes were compared. The blood samples were collected weekly, from the day before the treatment until the last week of CHRT/RT. The NMR spectra were acquired on A Bruker 400 MHz spectrometer at 310 K and analyzed using multivariate methods. Seven metabolites were found significantly to be altered solely by radiotherapy: N-acetyl-glycoprotein (NAG), N-acetylcysteine, glycerol, glycolate and the lipids at 0.9, 1.3 and 3.2 ppm. The NMR results were correlated with the tissue volumes receiving a particular dose of radiation. The influence of the irradiated volume on the metabolic profile is weak and mainly limited to sparse correlations with the inflammatory markers, creatinine and the lymphocyte count in RT and the branched-chain amino-acids in CHRT. This is probably due to the optimal planning and delivery of radiotherapy improving sparing of the surrounding normal tissues and minimizing the differences between the patients (caused by the tumor location and size).

Functional and oncological outcomes of salvage transoral robotic surgery: a comparative study

PURPOSE

Transoral robotic surgery (TORS) as a first-line therapy has been well-documented but evidence is missing regarding salvage therapy. The aim of this study is to compare the oncological and functional outcomes of TORS as a primary and salvage therapy.

METHODS

This retrospective monocentric study included 74 patients operated by a single surgeon and sorted out into two groups: primary treatment (PT) or Salvage treatment (ST) in case of previous history of radiation therapy. Patients were further stratified by tumour location: larynx and pharynx (lST vs lPT and pST vs pPT).

RESULTS

Forty-eight patients were included in PT group (64.9%) and 26 in ST group (35.1%). ST patients had more frequent cTis/T1 tumours (57.7% vs 29.2%, p = 0.0164) and no clinical lymph disease (3.8% vs 37.5%, p = 0.0016). Tracheostomy was more often performed in the ST group (57.7% vs 16.7%, p = 0.0003) and the lST subgroup (88.9% vs 9.1%, p < 0.0001). Gastric feeding tube placement was more frequent in the ST group (76.9% vs 33.3%, p = 0.0003), the pST subgroup (64.7% vs 15.4%, p = 0.0009) and the lST subgroup (100% vs 54.5%, p = 0.0297). We observed a trend for more postoperative complications in the ST group (69.2% vs 47.9%, p = 0.0783). The overall survival was lower in the ST group (p = 0.0004), and in the pST subgroup (p < 0.0001). The disease-free survival rate was lower in the ST group (p = 0.0001), the pST subgroup (p = 0.0002) and the lST subgroup (p = 0.0328).

CONCLUSION

This study confirms that survival and functional outcomes after salvage TORS are worse than in first line surgery.

125I seed implantation brachytherapy for glottic carcinoma: an experimental and clinical study

¹²⁵I seed implantation brachytherapy (ISIB) is the preferred treatment for prostate cancer. Is ISIB technically suitable for glottic carcinoma (GC)? This question has not been answered in the literature; thus, the present study was carried out to evaluate the feasibility and effect of ISIB on GC in animal and clinical studies. An animal model of Tu-212 cell laryngeal carcinoma xenografts (n = 20 animals) underwent ISIB treatments [experimental group (EG) using 0.8-mCi/seed, control group (CG) using 0-mCi/seed]; at 4 weeks, haematoxylin-eosin (HE) staining was performed, and the mRNA and protein expression of Bax, Bcl-2 and PCNA was analysed. Moreover, thirty healthy beagle dogs underwent ISIB under CT guidance (EG, 0.8 mCi/seed, CG, 0 mCi/seed), and injuries to the normal tissue were analysed by HE and Masson staining at 2, 4, and 8 weeks. Finally, twenty-one GC patients (T2-3N0M0) underwent percutaneous ISIB at a mean prescription dose of 116.8 Gy; the technical success, complications, local tumour response, voice quality, local progression and overall survival were analysed. The results showed that the xenograft tumours were significantly inhibited in the EG. The Bax protein levels were significantly increased in this group (P<0.05), while the Bcl-2 and PCNA protein levels were decreased (P<0.05). Moreover, the glottic injury scores increased with the dose accumulation (P<0.05), while the adjacent tissue did not show pathohistological injury, and the routine blood tests showed no change between the pre-treatment baseline levels and the levels 2, 4, or 8 weeks later (P>0.05). The clinical study found that the rate of technical success was 100% with no procedure-related complications; furthermore, complete response was achieved in all patients, and no local progression occurred. All patients survived and showed improvements in their voice quality (P<0.05) during the follow-up period (median 23.5 months). The results show that ISIB is a safe and effective treatment for GC; randomized controlled trials are needed to further evaluate its clinical efficacy.