Three weeks radiotherapy for T1 glottic cancer: the Christie and Royal Marsden Hospital Experience

Accelerated three-dimensional conformal radiotherapy for early-stage glottic cancer in reducing dose to the internal carotid artery and pharyngeal constrictor muscles

BACKGROUND

We evaluated clinical and dosimetric outcomes of radiotherapy using two anterior oblique portals (AOP), to reduce the dose to the bilateral internal carotid arteries (CAs) and pharyngeal constrictor muscle (PCM) during early-stage glottic cancer (ESGC) treatment.

METHODS

We identified patients with ESGC who underwent definitive radiotherapy between June 2014 and May 2020.

RESULTS

Among the 66 patients, 32 (48%) underwent radiotherapy using AOP, and the remaining underwent typical radiotherapy using parallel opposed lateral portals (POLP). The median follow-up duration was 53 months. No significant differences were observed in the 5-year local failure (0%/9.4%), progression-free survival (90.6%/90.8%), and overall survival (90.6%/91.0%) rates between the two groups. The grade ≥2 acute mucositis incidence rate was significantly lower in the AOP group (44%/85%). Radiotherapy using AOP maintained an adequate dose coverage to the target while markedly reducing the CAs and PCM doses.

CONCLUSION

Radiotherapy with AOP resulted in favorable clinical and dosimetric outcomes.

Intensity-Modulated Radiation Therapy for Early-Stage Squamous Cell Carcinoma of the Glottic Larynx: A Systematic Review and Meta-Analysis

PURPOSE

Early-stage squamous cell carcinoma of the glottic larynx is commonly treated with 2-dimensional or 3-dimensional conventional radiation therapy (CRT). Despite its use in other head and neck cancers, intensity-modulated radiation therapy (IMRT) remains controversial in this patient population.

METHODS AND MATERIALS

A systematic review was performed by querying 3 databases (Pubmed, Embase, Web of Science) for articles published between December 1, 2000 and September 2, 2022. Included studies reported outcomes in at least 10 patients treated with IMRT for early-stage glottic cancer. Data were extracted and reported following PRISMA standards. Pooled outcomes were estimated using random-effects models. Primary outcome was the rate of local failure (LF) following IMRT. Secondary outcomes included rates of regional failure (RF) following IMRT and rates of LF and RF following CRT.

RESULTS

A total of 15 studies (14 retrospective, 1 prospective) consisting of 2083 patients were identified. IMRT was used in 873 patients (64% T1, 28% T2). Multiple treatment (partial larynx, single vocal cord carotid sparing) and image-guided radiation therapy techniques were used. The pooled crude rate of LF was 7.6% (95% confidence inverval [CI], 3.6%-11.5%) and actuarial LF rates at 3 and 5 years were 6.3% (95% CI, 2.2%-10.3%) and 9.0% (95% CI, 4.4%-13.5%), respectively. The pooled crude rate of RF after IMRT was 1.5% (95% CI, 0.5%-2.5%). On metaregression analysis, increased rate of LF was significantly associated with T2 disease (P < .001) and grade 2 to 3 histology (P < .001). Treatment with CRT was reported in 738 patients (76% T1, 22% T2). Among the studies reporting outcomes of both modalities, there was no significant difference in LF (log odds ratio; P = .12) or RF (log odds ratio; P = .58) between IMRT or CRT.

CONCLUSIONS

In patients with early-stage glottic cancer, retrospective data suggests local and regional control are similar for patients treated with IMRT and CRT. Additional prospective studies with uniform methods of volume delineation and image guidance are needed to confirm the efficacy of IMRT.

Overview of glottic laryngeal cancer treatment recommendation changes in the NCCN guidelines from 2011 to 2022

BACKGROUND

The treatment of glottic cancer remains challenging, especially with regard to morbidity reduction and larynx preservation rates. The National Comprehensive Cancer Network (NCCN) has published guidelines to aid decision-making about this treatment according to the tumor site, clinical stage, and patient medical status.

AIM

The present review was conducted to identify changes in the NCCN guidelines for glottic cancer treatment made between 2011 and 2022 and to describe the published evidence concerning glottic cancer treatment and oncological outcomes in the same time period.

METHODS AND RESULTS

Clinical practice guidelines for head and neck cancer published from 2011 up to 2022 were obtained from the NCCN website (www.NCCN.org). Data on glottic cancer treatment recommendations were extracted, and descriptive analysis was performed. In addition, a review of literature registered in the PubMed database was performed to obtain data on glottic cancer management protocols and treatment outcomes from randomized controlled trials, systematic reviews, and meta-analyses published from 2011 to 2022. In total, 24 NCCN guidelines and updates and 68 relevant studies included in the PubMed database were identified. The main guideline changes made pertained to surgical and systemic therapies, the consideration of adverse features, and new options for the treatment of metastatic disease at initial presentation. Early-stage glottic cancer received the most research attention, with transoral endoscopic laser surgery and radiotherapy assessed and compared as the main treatment modalities. Reported associations between treatment types and survival rates for this stage of glottic cancer appear to be similar, but functional outcomes can be highly compromised.

CONCLUSION

NCCN panel members provide updated recommendations based on currently accepted treatment approaches for glottic cancer, constantly reviewing new surgical and non-surgical techniques. The guidelines support decision-making about glottic cancer treatment that should be individualized and prioritize patients' quality of life, functionality, and preferences.

Real-Time Tracking of Laryngeal Motion via the Surface Depth-Sensing Technique for Radiotherapy in Laryngeal Cancer Patients

Radiotherapy (RT) is an important modality for laryngeal cancer treatment to preserve laryngeal function. During beam delivery, laryngeal motion remains uncontrollable and may compromise tumor-targeting efficacy. We aimed to examine real-time laryngeal motion by developing a surface depth-sensing technique with preliminary testing during RT-based treatment of patients with laryngeal cancer. A surface depth-sensing (SDS) camera was set up and integrated into RT simulation procedures. By recording the natural swallowing of patients, SDS calculation was performed using the Pose Estimation Model and deep neural network technique. Seven male patients with laryngeal cancer were enrolled in this prospective study. The calculated motion distances of the laryngeal prominence (mean ± standard deviation) were 1.6 ± 0.8 mm, 21.4 ± 5.1 mm, 6.4 ± 3.3 mm, and 22.7 ± 4.9 mm in the left-right, cranio-caudal, and anterior-posterior directions and for the spatial displacement, respectively. The calculated differences in the 3D margins for generating the planning tumor volume by senior physicians with and without SDS data were -0.7 ± 1.0 mm (-18%), 11.3 ± 6.8 mm (235%), and 1.8 ± 2.6 mm (45%) in the left-right, cranio-caudal, and anterior-posterior directions, respectively. The SDS technique developed for detecting laryngeal motion during swallowing may be a practical guide for individualized RT design in the treatment of laryngeal cancer.

Cost-effectiveness of hypofractionated versus conventional fractionated radiotherapy for the treatment of men with early glottic cancer: a study in the Brazilian public and private health system

BACKGROUND

This study aims to evaluate whether hypofractionated radiotherapy (HYPOFRT) is a cost-effective strategy than conventional fractionated radiotherapy (CFRT) for early-stage glottic cancer (ESGC) in the Brazilian public and private health systems.

METHODS

Adopting the perspective of the Brazilian public and private health system as the payer, a Markov model with a lifetime horizon was built to delineate the health states for a cohort of 65-year-old men after with ESGC treated with either HYPOFRT or CFRT. Probabilities of controlled disease, local failure, distant metastasis, and death and utilities scores were extracted from randomized clinical trials. Costs were based on the public and private health system reimbursement values.

RESULTS

In the base case scenario, for both the public and private health systems, HYPOFRT dominated CFRT, being more effective and less costly, with a negative ICER of R$264.32 per quality-adjusted life-year (QALY) (public health system) and a negative ICER of R$2870.69/ QALY (private health system). The ICER was most sensitive to the probability of local failure, controlled disease, and salvage treatment costs. For the probabilistic sensitivity analysis, the cost-effectiveness acceptability curve indicates that there is a probability of 99.99% of HYPOFRT being cost-effective considering a willingness-to-pay threshold of R$2,000 ($905.39) per QALY (public sector) and willingness-to-pay threshold of R$16,000 ($7243.10) per QALY (private sector). The results were robust in deterministic and probabilistic sensitivity analyses.

CONCLUSIONS

Considering a threshold of R$ 40,000 per QALY, HYPOFRT was cost-effective compared to CFRT for ESGC in the Brazilian public health system. The Net Monetary Benefit (NMB) is approximately 2,4 times (public health system) and 5,2 (private health system) higher for HYPOFRT than CFRT, which could open the opportunity of incorporating new technologies.

Radiation for Early Glottic Cancer

Multidisciplinary evaluation of early-stage glottic cancer facilitates optimal treatment with either surgery or radiation therapy. Standard of care radiation treatment of early-stage glottic cancer continues to be three-dimensional opposed lateral fields to include the whole larynx. Modern radiation treatment techniques are allowing studies to examine the efficacy and toxicity of altered doses and treatment volumes. Advanced techniques, such as stereotactic body radiation therapy or single-vocal cord irradiation, are not yet considered standard of care for early-stage glottic cancer and should be performed at institutions with clinical trials to ensure adequate expertise and quality assurance.

VoiceS: voice quality after transoral CO2 laser surgery versus single vocal cord irradiation for unilateral stage 0 and I glottic larynx cancer-a randomized phase III trial

Background

Surgery and radiotherapy are well-established standards of care for unilateral stage 0 and I early-stage glottic cancer (ESGC). Based on comparative studies and meta-analyses, functional and oncological outcomes after both treatment modalities are similar. Historically, radiotherapy (RT) has been performed by irradiation of the whole larynx. However, only the involved vocal cord is being treated with recently introduced hypofractionated concepts that result in 8 to 10-fold smaller target volumes. Retrospective data argues for an improvement in voice quality with non-inferior local control. Based on these findings, single vocal cord irradiation (SVCI) has been implemented as a routine approach in some institutions for ESGC in recent years. However, prospective data directly comparing SVCI with surgery is lacking. The aim of VoiceS is to fill this gap.

Methods

In this prospective randomized multi-center open-label phase III study with a superiority design, 34 patients with histopathologically confirmed, untreated, unilateral stage 0-I ESGC (unilateral cTis or cT1a) will be randomized to SVCI or transoral CO₂-laser microsurgical cordectomy (TLM). Average difference in voice quality, measured by using the voice handicap index (VHI) will be modeled over four time points (6, 12, 18, and 24 months). Primary endpoint of this study will be the patient-reported subjective voice quality between 6 to 24 months after randomization. Secondary endpoints will include perceptual impression of the voice via roughness – breathiness – hoarseness (RBH) assessment at the above-mentioned time points. Additionally, quantitative characteristics of voice, loco-regional tumor control at 2 and 5 years, and treatment toxicity at 2 and 5 years based on CTCAE v.5.0 will be reported.

Discussion

To our knowledge, VoiceS is the first randomized phase III trial comparing SVCI with TLM. Results of this study may lead to improved decision-making in the treatment of ESGC.

Trial registration

ClinicalTrials.gov NCT04057209. Registered on 15 August 2019. Cantonal Ethics Committee KEK-BE 2019-01506

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06841-5.

Outcomes of carotid sparing intensity-modulated radiotherapy for early stage glottic cancer in 201 patients: Multicenter study of Turkish Radiation Oncology Society/TROD-01-007

BACKGROUND

To assess and report clinical outcomes after carotid sparing intensity-modulated radiotherapy for early stage laryngeal cancer.

METHODS

We retrospectively analyzed 201 patients with early stage glottic laryngeal cancer treated with carotid sparing intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) techniques in six TROD centers.

RESULTS

After a median follow-up of 31 months the actuarial 1- and 3-year local and locoregional control rates were 99.4% and 94.7%, 98.4% and 93%, respectively. T classification, anterior commissure involvement, IMRT technique, and type of fractionation were not found to be prognostic for local control. Overall, eight patients had lost their organ function due to recurrence or toxicity. Grade 3 and 4 acute laryngeal edema was seen in eight (4%) and one (0.5%) of patients, respectively. Grade 3 and 4 late laryngeal edema developed in two (1%) and one patient (0.5%), respectively.

CONCLUSION

Oncologic outcomes of patients treated with carotid sparing IMRT were excellent; comparable with historical series, with acceptable side effects. Longer follow-up is needed to estimate long term effect on stroke.

Hypofractionated radiotherapy for early stage glottic cancer: efficacy of 3.5 Gy per fraction

Purpose

The purpose of this study was to evaluate the treatment outcomes and toxicity profile of patients with early glottic cancer who underwent hypofractionated radiation therapy (RT) with 3.5 Gy per fraction.

Materials and Methods

A retrospective review was performed of the medical records of 35 patients with early stage (T1-2N0M0) glottic cancer who underwent definitive RT. The dose fractionation scheme was 59.5 Gy in 17 fractions. Posterior commissure was excluded from the clinical target volume (CTV) for 26 patients (74.3%) without glottic lesions close to this region.

Results

With a median follow-up of 16.23 months (range, 6.82 to 67.15 months), no local, regional, or distant recurrence was reported. Acute hoarseness (65.7%), mucositis (68.6%), radiation dermatitis (60.0%) was frequent. One patient (2.9%) reported grade 3 acute toxicity (mucositis) and there was no grade 4–5 acute toxicity. There was no grade ≥3 late toxicities; however, grade 1 late intermittent hoarseness was frequent (45.7%). The receiver operative characteristic analysis revealed that mean hypopharyngeal dose was predictive for acute grade ≥2 mucositis (area under the curve=0.9314; 95% confidence interval, 0.8524–1). The optimal threshold of mean hypopharyngeal dose for occurrence of acute grade ≥2 mucositis was 26.31 Gy, with a specificity and sensitivity of 83.3% and 88.2%, respectively.

Conclusion

Hypofractionated RT with fraction size of 3.5 Gy for early glottic cancer is effective. The hypopharyngeal mean dose could predict the occurrence of grade ≥2 acute mucositis. The posterior commissure can be safely excluded from the CTV.

Single vocal cord irradiation for early-stage glottic cancer: Excellent local control and favorable toxicity profile

OBJECTIVE

To validate the earlier reported promising oncologic outcomes and favorable toxicity profile following single vocal cord irradiation (SVCI) in an expanded cohort of patients with early-stage glottic cancer treated at our institute with longer follow-up time.

MATERIALS AND METHODS

Between February 2011 and January 2020, 111 consecutive patients with early-stage glottic cancer were treated with SVCI to the whole involved vocal cord (58.08 Gy, given in 16 fractions of 3.63 Gy). Setup verification was done using cone-beam CT, prior to each fraction. The endpoints were local control (LC), overall survival (OS), grade ≥ 3 toxicity and voice quality assessment using voice-handicap index (VHI) questionnaires.

RESULTS

Median follow-up was 41 months (range; 8-84). Two patients developed in-field local failure (LF). The 3- and 5-year LC rates were 99.1% and 97.1%, respectively. As both patients with LF were successfully salvaged with total laryngectomy, the 5-year ultimate LC-rates was 99%. The 5-years OS was 80.6%. All patients finished treatment without any interruption. No patients developed acute grade ≥ 3 toxicity. Late grade 3 toxicity was reported in 7 patients (6.5%) out of 108 patients evaluable for late toxicity; 2 because of severe hoarseness and 5 because of laryngeal radionecrosis (4.5%). The 5-years laryngectomy-free survival was 98.1%. The VHI-scores improved over time, only 22% of patients had VHI > 30 at 3-years post-radiotherapy, compared to 38% at baseline.

CONCLUSIONS

Local control rate and laryngectomy-free survival of SVCI are excellent with favorable toxicity profile and good VHI-score. These results validate our early results.

Hypofractionated radiotherapy versus conventional radiotherapy in early glottic cancer T1-2N0M0: A randomized study

Objective

Glottic cancer has an excellent probability of cure. The early glottic cancer is usually treated by radiotherapy with different fractionation schedules. The aim of this study was to compare conventional versus hypofractionated radiotherapy with respect to overall survival and disease-free survival.

Materials and Methods

A total of fifty patients with T1-2N0M0 glottic cancer with no previous treatment history were prospectively randomized into two arms. In Arm A (Study), patients received a total of 55 Gy in 20# at 2.75 Gy/#, 5 days a week. In Arm B (Control), patients received a total of 66 Gy in 33# at 2 Gy/#, 5 days a week. Disease response was evaluated by the WHO criteria at the end of treatment, then at 1, 2, and 3 months to complete their 6-month follow-up. Overall survival and disease-free survival were evaluated at 1, 2, and 3 years.

Results

Overall, 100% of patients in the study arm and 96% of patients in the control arm had complete response after 6 months. Overall survival rates at 1, 2, and 3 years were 96%, 96%, and 88%, respectively, in the study arm, while in the control arm, these values were 92%, 84%, and 80%, respectively, and the difference was not statistically significant (P > 0.05). Disease-free survival at 3 years was 88% in the study arm and 80% in the control arm.

Conclusion

The study suggests that hypofractionated regimen may be better in local control and symptomatic relief with the added advantage of shorter treatment time, which offers better patient compliance and advantageous in busy setups where there is heavy patient load.

[Radiation Oncology - Recent Status]

Radiation Oncology - Recent Status Abstract. We summarize the most important developments and innovations in the field over the past years and illustrate resulting external radiation treatment schedules and related treatment tolerance, focusing on hypofractionation.

[Radiotherapy for patients with early-stage glottic squamous cell carcinoma of the larynx: Interest of hypofractionation?]

Hypofractionated radiotherapy of early-stage squamous cell carcinoma of the glottic larynx is a promising treatment option. This can be divided into radiotherapy with moderate hypofractionation (up to 2.5Gy per fraction), more intense hypofractionation (between 2.5 and 4.5Gy per fraction) and stereotactic radiotherapy (above 4.5Gy per fraction). Most studies evaluating moderate hypofractionation show a local control rate between 85 and 95%. Acute laryngeal toxicity is superior to conventional treatment, but only for grades 1 and 2, with no significant difference reported for severe toxicity. Stereotactic radiotherapy in this pathology is also an emerging entity, but some authors have reported significant toxicity. There are currently no standardized guidelines for treatment and management regimen. We conducted a systemic review of published prospective and retrospective trials to evaluate efficacy, toxicity, and discuss future directions.

Ionizing radiation exposure of stem cell-derived chondrocytes affects their gene and microRNA expression profiles and cytokine production

Human induced pluripotent stem cells (hiPSCs) can be differentiated into chondrocyte-like cells. However, implantation of these cells is not without risk given that those transplanted cells may one day undergo ionizing radiation (IR) in patients who develop cancer. We aimed to evaluate the effect of IR on chondrocyte-like cells differentiated from hiPSCs by determining their gene and microRNA expression profile and proteomic analysis. Chondrocyte-like cells differentiated from hiPSCs were placed in a purpose-designed phantom to model laryngeal cancer and irradiated with 1, 2, or 3 Gy. High-throughput analyses were performed to determine the gene and microRNA expression profile based on microarrays. The composition of the medium was also analyzed. The following essential biological processes were activated in these hiPSC-derived chondrocytes after IR: "apoptotic process", "cellular response to DNA damage stimulus", and "regulation of programmed cell death". These findings show the microRNAs that are primarily responsible for controlling the genes of the biological processes described above. We also detected changes in the secretion level of specific cytokines. This study demonstrates that IR activates DNA damage response mechanisms in differentiated cells and that the level of activation is a function of the radiation dose.

Practice recommendations for risk-adapted head and neck cancer radiotherapy during the COVID-19 pandemic: An ASTRO-ESTRO consensus statement

PURPOSE

Because of the unprecedented disruption of health care services caused by the COVID-19 pandemic, the American Society of Radiation Oncology (ASTRO) and the European Society for Radiotherapy and Oncology (ESTRO) identified an urgent need to issue practice recommendations for radiation oncologists treating head and neck cancer (HNC) in a time of limited resources and heightened risk for patients and staff.

METHODS AND MATERIALS

A panel of international experts from ASTRO, ESTRO, and select Asia-Pacific countries completed a modified rapid Delphi process. Topics and questions were presented to the group, and subsequent questions were developed from iterative feedback. Each survey was open online for 24 hours, and successive rounds started within 24 hours of the previous round. The chosen cutoffs for strong agreement (≥80%) and agreement (≥66%) were extrapolated from the RAND methodology. Two pandemic scenarios, early (risk mitigation) and late (severely reduced radiation therapy resources), were evaluated. The panel developed treatment recommendations for 5 HNC cases.

RESULTS

In total, 29 of 31 of those invited (94%) accepted, and after a replacement 30 of 30 completed all 3 surveys (100% response rate). There was agreement or strong agreement across a number of practice areas, including treatment prioritization, whether to delay initiation or interrupt radiation therapy for intercurrent SARS-CoV-2 infection, approaches to treatment (radiation dose-fractionation schedules and use of chemotherapy in each pandemic scenario), management of surgical cases in event of operating room closures, and recommended adjustments to outpatient clinic appointments and supportive care.

CONCLUSIONS

This urgent practice recommendation was issued in the knowledge of the very difficult circumstances in which our patients find themselves at present, navigating strained health care systems functioning with limited resources and at heightened risk to their health during the COVID-19 pandemic. The aim of this consensus statement is to ensure high-quality HNC treatments continue, to save lives and for symptomatic benefit.

Is Single Cord Irradiation Going to Be a New Standard for T1a Glottic Carcinoma?

Purpose and Objective: To evaluate the disease-free survival, overall survival, dosimetric, and voice handicap index (VHI) results of T1a glottic invasive squamous cell carcinoma (SCC) patients who underwent hypofractionated single vocal cord irradiation (HSVCI).

Materials and Methods: The data of 18 patients with stage T1a glottic SCC were collected prospectively and analyzed retrospectively between July 2016 and July 2019. Patients were immobilized using a custom-fitted thermoplastic face and shoulder mask in hyperextension position. The CT scan was performed with 1-mm-thick slices. A planned target volume (PTV) margin of 3 mm was given to clinical target volume (CTV) in all directions, and 13 organs at risk were identified. Patients were prescribed a total of 5760–5808 cGy in 15–16 fractions. Patients had daily cone-beam computed tomography (CBCT), and the treatment was carried out with the physician. VHI test was applied to patients before and at the end of radiotherapy (RT) and 1, 2, 3, 4, and 6 months after the completion of RT.

Results: Local control and overall survival rate is 100% for a median of 18 months (6–44 months) of follow-up. A patient was diagnosed with 2nd primary lung cancer and active treatment still continues. All patients completed the treatment within the scheduled time. Grade 1–2 dysphagia and dermatitis occurred in all patients, and no grade 3 and above side effects were observed. The mean values of VHI were 37.00, 39.83, 38.28, 17.17, 12.22, 8.56, and 6.06 at the beginning of RT, at the end of RT, and 1, 2, 3, 4, and 6 months after RT, respectively.

Conclusion: Compared to surgery and conventional laryngeal radiotherapy, HSVCI is an alternative treatment method for T1a glottic cancer by reducing the treatment time to 3 weeks, facilitating recurrence treatment, and providing effective sound quality without compromising local control. Considering that ~80% of recurrences in glottic cancer occur within the first 2 years, 100% local control in a median of 18 months is extremely successful, but long-term follow-up is essential to observe possible late side effects.

Practice Recommendations for Risk-Adapted Head and Neck Cancer Radiation Therapy During the COVID-19 Pandemic: An ASTRO-ESTRO Consensus Statement

PURPOSE

Because of the unprecedented disruption of health care services caused by the COVID-19 pandemic, the American Society of Radiation Oncology (ASTRO) and the European Society for Radiotherapy and Oncology (ESTRO) identified an urgent need to issue practice recommendations for radiation oncologists treating head and neck cancer (HNC) in a time of limited resources and heightened risk for patients and staff.

METHODS AND MATERIALS

A panel of international experts from ASTRO, ESTRO, and select Asia-Pacific countries completed a modified rapid Delphi process. Topics and questions were presented to the group, and subsequent questions were developed from iterative feedback. Each survey was open online for 24 hours, and successive rounds started within 24 hours of the previous round. The chosen cutoffs for strong agreement (≥80%) and agreement (≥66%) were extrapolated from the RAND methodology. Two pandemic scenarios, early (risk mitigation) and late (severely reduced radiation therapy resources), were evaluated. The panel developed treatment recommendations for 5 HNC cases.

RESULTS

In total, 29 of 31 of those invited (94%) accepted, and after a replacement 30 of 30 completed all 3 surveys (100% response rate). There was agreement or strong agreement across a number of practice areas, including treatment prioritization, whether to delay initiation or interrupt radiation therapy for intercurrent SARS-CoV-2 infection, approaches to treatment (radiation dose-fractionation schedules and use of chemotherapy in each pandemic scenario), management of surgical cases in event of operating room closures, and recommended adjustments to outpatient clinic appointments and supportive care.

CONCLUSIONS

This urgent practice recommendation was issued in the knowledge of the very difficult circumstances in which our patients find themselves at present, navigating strained health care systems functioning with limited resources and at heightened risk to their health during the COVID-19 pandemic. The aim of this consensus statement is to ensure high-quality HNC treatments continue, to save lives and for symptomatic benefit.

The 3 Bs of cancer care amid the COVID-19 pandemic crisis: "Be safe, be smart, be kind"-A multidisciplinary approach increasing the use of radiation and embracing telemedicine for head and neck cancer

Because of the national emergency triggered by the coronavirus disease 2019 (COVID-19) pandemic, government-mandated public health directives have drastically changed not only social norms but also the practice of oncologic medicine. Timely head and neck cancer (HNC) treatment must be prioritized, even during emergencies. Because severe acute respiratory syndrome coronavirus 2 predominantly resides in the sinonasal/oral/oropharyngeal tracts, nonessential mucosal procedures are restricted, and HNCs are being triaged toward nonsurgical treatments when cures are comparable. Consequently, radiation utilization will likely increase during this pandemic. Even in radiation oncology, standard in-person and endoscopic evaluations are being restrained to limit exposure risks and preserve personal protective equipment for other frontline workers. The authors have implemented telemedicine and multidisciplinary conferences to continue to offer standard-of-care HNC treatments during this uniquely challenging time. Because of the lack of feasibility data on telemedicine for HNC, they report their early experience at a high-volume cancer center at the domestic epicenter of the COVID-19 crisis.

Intensity-modulated radiotherapy for stage I glottic cancer: a short-term outcomes compared with three-dimensional conformal radiotherapy

Purpose

To investigate the differences in treatment outcomes between two radiation techniques, intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT).

Materials and Methods

We retrospectively analyzed 160 (IMRT = 23, 3DCRT = 137) patients with stage I glottic cancer treated from January 2005 through December 2016. The IMRT was performed with TomoTherapy (16 patients), volumetric-modulated arc therapy (6 patients), and step-and-shoot technique (1 patient), respectively. The 3DCRT was performed with bilateral parallel opposing fields. The median follow-up duration was 30 months (range, 31 to 42 months) in the IMRT group and 65 months (range, 20 to 143 months) in the 3DCRT group.

Results

The 5-year overall survival and 3-year local control rates of the 160 patients were 95.7% and 91.4%, respectively. There was no significant difference in 3-year local control rates between the IMRT and 3DCRT groups (94.4% vs. 91.0%; p = 0.587). Thirteen of 137 patients in the 3DCRT group had recurrences. In the IMRT group, one patient had a recurrence at the true vocal cord. Patients treated with IMRT had less grade 2 skin reaction than the 3DCRT group, but this had no statistical significance (4.3% vs. 21.2%; p = 0.080).

Conclusion

IMRT had comparable outcomes with 3DCRT, and a trend of less acute skin reaction in stage I glottic cancer patients

The prognostic value of anterior commissure involvement in T1 glottic cancer: A systematic review and meta-analysis

OBJECTIVE

The anterior commissure is considered a laryngeal subsite, but it is not taken into account in the current T-staging system. The impact of anterior commissure involvement (ACI) on the oncologic outcomes of T1 glottic tumors has not been well defined and remains controversial. The aim of this study was to assess the influence of ACI in the prognosis of T1 glottic tumors.

METHODS

A systematic review and meta-analysis of observational studies was performed by including studies published up to July 2019. Studies were selected if they had investigated the local control rate (LCR) at 5 years of clinical stage I (T1 and N0) glottic squamous cell carcinoma with and without ACI. The difference in LCR at 5 years between T1 glottic tumors without and with ACI was evaluated.

RESULTS

The meta-analysis showed that the difference in LCR at 5 years between T1 glottic tumors without and with ACI is 12% (95% confidence interval: 8%-16%, p < 0,0001, I² = 34.81%).

CONCLUSIONS

Our study pointed out that the anterior commissure involvement is a negative prognostic factor in LCR at 5 years for T1 glottic tumors. Our results suggest the need to consider ACI in the T staging of glottic tumors. Laryngoscope, 130:1932-1940, 2020.

Involvement of the Anterior Commissure in Early Glottic Cancer (Tis-T2): A Review of the Literature

Background: The impact of the anterior commissure (AC) involvement on prognosis in laryngeal cancer remains a topic of discussion with inconsistent results in the literature. This review examines AC involvement as a prognostic factor in patients with early glottic cancer (Tis-T2) treated with radiotherapy or transoral laser microsurgery (TLM). Methods: A systematic literature search was performed. Due to the heterogeneity of the data, no meta-analysis was implemented. Weighted averages were calculated if the appropriate data were extractable. Results: Thirty-four studies on radiotherapy and 23 on TLM fit the inclusion criteria. The majority of studies for both radiotherapy (67.7%) and TLM (75.0%) did not report a significant impact on oncological outcomes. Weighted averages were slightly lower in patients with AC involvement. The two studies that applied a more detailed classification showed a significant impact on the amount of AC involvement. Conclusions: Binary variables (yes/no) for AC involvement lead to inconsistent results. Studies that use more detailed classifications of the AC show that there is a significant impact on the outcome. To further elucidate the role of the AC, detailed stratification of tumors involving the AC need to be investigated in further studies for both treatment modalities.

Hypofractionated radiotherapy for early glottic cancer: a retrospective interim analysis of a single institution

PURPOSE

To evaluate the results of hypofractionated radiotherapy (HFX) for early glottic cancer.

MATERIALS AND METHODS

Eighty-five patients with cT1-2N0M0 squamous cell carcinoma of the glottis who had undergone HFX, performed using intensity-modulated radiotherapy (IMRT, n = 66) and three-dimensional conformal radiotherapy (3D CRT, n = 19) were analyzed. For all patients, radiotherapy was administered at 60.75 Gy in 27 fractions. Forty-three patients received a simultaneous integrated boost (SIB) of 2.3-2.5 Gy per tumor fraction.

RESULTS

The median follow-up duration was 29.9 months (range, 5.5 to 76.5 months). All patients achieved complete remission at a median of 50 days after the end of radiotherapy (range, 14 to 206 days). The 5-year rates for locoregional recurrence-free survival was 88.1%, and the 5-year overall survival rate was 86.2%. T2 stage was a prognostic factor for locoregional recurrencefree survival after radiotherapy (p = 0.002). SIB for the tumor did not affect disease control and survival (p = 0.191 and p = 0.387, respectively). No patients experienced acute or chronic toxicities of ≥grade 3. IMRT significantly decreased the dose administered to the carotid artery as opposed to 3D CRT (V35, p < 0.001; V50, p < 0.001).

Conclusions

Patients treated with HFX achieved acceptable locoregional disease control rates and overall survival rates compared with previous HFX studies. A fraction size of 2.25 Gy provided good disease control regardless of SIB administration.

Outcomes of Early-stage Glottic Carcinoma Treated with Radiation Therapy: A Single Institution Experience

Objective: To evaluate the outcomes of radical intent radiation therapy in early glottic carcinoma (EGC), including local control rate (LCR), disease-free survival (DFS), death specific free survival (DSFS), and overall survival (OS) rates, in Saudi patients treated at a single institution. 

Materials and methods: This is an institutional review board (IRB) approved, retrospective study of 27 patients with T1-2 N0 M0, early glottic carcinoma (EGC) who were treated from 2010 to 2015 at our institution with different radiotherapy (RT) fractionation regimens. The regimens included six different fractionation schedules of radiotherapy (RT): 50 Gy (20 x 2.5 Gy) dose prescribed to 95% isodose line, 52.4 Gy (20 x 2.52 Gy), 63 Gy (28 x 2.25 Gy), 66 Gy (33 x 2 Gy), and 70 Gy (35 x 2 Gy). The cohort was stratified into two groups, ≤ 52.5 Gy (n=15) and > 52.5 Gy (n=12). The median follow-up of all patients was 31.7 months (range 7-82).

Results: The mean age of the cohort was 64.5 years (median 65, range: 41-83). Eleven patients (40.7%) had a history of smoking. The majority of the cohort was with T1a EGC (70.4%, n=19), and anterior commissure invasion was seen in three patients (11.1%). The mean RT doses were 55.6 Gy (range: 50-70). The five-year LCR, DFS, DSFS, and OS rates were 83.1%, 80.0%, 96.2%, and 92.6%, respectively. The LCR rates for those receiving a dose of 52.5 Gy or less were 61.3 months compared to 89.5 months for those who received more than 52.5 Gy (p=0.994). Non-smokers and patients with an unknown smoking history achieved a five-year LCR of 100%, while patients with a positive smoking history achieved a five-year LCR of 60.6% (p=0.044).

Conclusion: Radiation therapy for EGC in our patients showed reasonable five-year LCR with larynx preservation at 83.1%, DFS 80.0%, five-year OS rate 92.6%, and DSFS rate 96.2%. We found that smoking had a significant correlation with LCR. However, large prospective trials are warranted to evaluate the efficacy of overall treatment time, dose per fraction of above 2 Gy, and smoking effect.

Conventional fractionation should not be the standard of care for T2 glottic cancer

Background

The aim of this study was to report outcomes and late toxicity following hypofractionated accelerated radiotherapy for T2 glottic cancers. We highlight the importance of hypofractionated treatments with shorter overall treatment times, in improving outcomes for T2 glottic cancers. We also compare the biologically effective dose of hypofractionated regimes, with conventional fractionation.

Methods

One hundred twelve patients with T2 glottic cancer were treated between January 1999 and December 2005. All patients were prescribed a hypofractionated accelerated radiotherapy dose of 52.5 Gray in 3.28 Gray per fraction, delivered over 22 days. Radiobiological calculations were used to assess the relationship of fraction size and overall treatment time on local control outcomes and late toxicity.

Results

The 5-year overall survival was 67%, the 5-year local control was 82%, and the 5-year disease-specific survival was 90%. The respective 5-year local control for T2a and T2b disease was 88.8 and 70.8% (p = 0.032). Severe late toxicity occurred in two patients (1.8%). Radiobiological calculations showed an increase in local control of nearly 12%, with a 10 Gray increase in biologically effective dose.

Conclusion

This study has demonstrated that accelerated hypofractionated regimes have improved local control and similar late toxicity compared with conventional fractionation schedules. This supports the use of hypofractionated regimes as the standard of care for early glottic laryngeal cancers.

Prediction of local control in early glottic carcinoma using the maximum standardised uptake value

PURPOSE

This retrospective study aimed to determine whether the maximum standardised uptake value (SUV_max) can predict local tumour control in early glottic cancer (Tis, T1, and T2).

PATIENTS AND METHODS

Fifty-nine patients treated with definitive radiotherapy for early glottic cancer between 2003 and 2011 were enrolled. We evaluated the SUV_max in the region of interest around the original tumour site. Local tumour control and survival were estimated using Kaplan-Meier curves. Receiver operating characteristic curves were used to assess the optimal SUV_max cut-off for predicting local control.

RESULTS

As determined by laryngoscopy, all patients achieved a complete response. Eleven patients experienced local recurrence, while no distant metastasis occurred. One patient died due to local recurrence, while five lost their larynxes. The median follow-up was 61.5 (range: 6.2-123.4) months. The five-year local progression-free survival was 84.7%, and larynx preservation was possible in 89.6% of cases. The median SUV_max was 2.2. The optimal SUV_max for predicting local tumour control was identified as 3.4. Patients with glottic cancers with an SUV_max>3.4 showed a significantly lower local progression-free survival rate than those with tumours with an SUV_max<3.4 (five-year local progression-free survival rate: 53.4% vs. 95.4%, P<0.01). Multivariate analysis confirmed that a high SUV_max was an independent predictive factor for local progression-free survival (P=0.006).

CONCLUSION

The use of (¹⁸F)-fluorodeoxyglucose-positron emission tomography for evaluation of the SUV_max is useful to predict local progression-free survival in patients with early glottic cancer treated by radiation. Early glottic cancer with a high SUV_max may require aggressive local treatment and careful surveillance.

SBRT for early-stage glottic larynx cancer-Initial clinical outcomes from a phase I clinical trial

Purpose

To confirm safety and feasibility of hypofractionated SBRT for early-stage glottic laryngeal cancer.

Methods

Twenty consecutive patients with cTis-T2N0M0 carcinoma of glottic larynx were enrolled. Patients entered dose-fractionation cohorts of incrementally shorter bio-equivalent schedules starting with 50 Gy in 15 fractions (fx), followed by 45 Gy/10 fx and, finally, 42.5 Gy/5 fx. Maximum combined CTV-PTV expansion was limited to 5 mm. Patients were treated on a Model G5 Cyberknife (Accuray, Sunnyvale, CA).

Results

Median follow-up is 13.4 months (range: 5.6–24.6 months), with 12 patients followed for at least one year. Maximum acute toxicity consisted of grade 2 hoarseness and dysphagia. Maximum chronic toxicity was seen in one patient treated with 45 Gy/10 fx who continued to smoke >1 pack/day and ultimately required protective tracheostomy. At 1-year follow-up, estimated local disease free survival for the full cohort was 82%. Overall survival is 100% at last follow-up.

Conclusions

We were able to reduce equipotent total fractions of SBRT from 15 to 5 without exceeding protocol-defined acute/subacute toxicity limits. With limited follow-up, disease control appears comparable to standard treatment. We continue to enroll to the 42.5 Gy/5 fx cohort and follow patients for late toxicity.

Trial registration

ClinicalTrials.gov NCT01984502

Laryngeal cancer: United Kingdom National Multidisciplinary guidelines

This is the official guideline endorsed by the specialty associations involved in the care of head and neck cancer patients in the UK. Significantly new data have been published on laryngeal cancer management since the last edition of the guidelines. This paper discusses the evidence base pertaining to the management of laryngeal cancer and provides updated recommendations on management for this group of patients receiving cancer care.

Online dosimetric evaluation of larynx SBRT: A pilot study to assess the necessity of adaptive replanning

Purpose

We have initiated a multi‐institutional phase I trial of 5‐fraction stereotactic body radiotherapy (SBRT) for Stage III–IVa laryngeal cancer. We conducted this pilot dosimetric study to confirm potential utility of online adaptive replanning to preserve treatment quality.

Methods

We evaluated ten cases: five patients enrolled onto the current trial and five patients enrolled onto a separate phase I SBRT trial for early‐stage glottic larynx cancer. Baseline SBRT treatment plans were generated per protocol. Daily cone‐beam CT (CBCT) or diagnostic CT images were acquired prior to each treatment fraction. Simulation CT images and target volumes were deformably registered to daily volumetric images, the original SBRT plan was copied to the deformed images and contours, delivered dose distributions were re‐calculated on the deformed CT images. All of these were performed on a commercial treatment planning system. In‐house software was developed to propagate the delivered dose distribution back to reference CT images using the deformation information exported from the treatment planning system. Dosimetric differences were evaluated via dose‐volume histograms.

Results

We could evaluate dose within 10 minutes in all cases. Prescribed coverage to gross tumor volume (GTV) and clinical target volume (CTV) was uniformly preserved; however, intended prescription dose coverage of planning treatment volume (PTV) was lost in 53% of daily treatments (mean: 93.9%, range: 83.9–97.9%). Maximum bystander point dose limits to arytenoids, parotids, and spinal cord remained respected in all cases, although variances in carotid artery doses were observed in a minority of cases.

Conclusions

Although GTV and CTV SBRT dose coverage is preserved with in‐room three‐dimensional image guidance, PTV coverage can vary significantly from intended plans and dose to critical structures may exceed tolerances. Online adaptive treatment re‐planning is potentially necessary and clinically applicable to fully preserve treatment quality. Confirmatory trial accrual and analysis remains ongoing.

Hypofractionated accelerated radiotherapy in T1-3 N0 cancer of the larynx: A prospective cohort study with historical controls

AIM

The goal of this prospective study was to assess the effectiveness of a hypofractionated accelerated regime in treatment of the larynx cancer.

BACKGROUND

Multiple radiotherapy delivery regimes are used for treatment of the larynx cancer. Hypofractionated regimes could provide similar results with reduced use of radiotherapy facilities.

MATERIAL AND METHODS

223 patients with squamous cell carcinoma of the upper or middle larynx have been treated with 63 Gy delivered in 28 fractions of 2.25 Gy during 38 days, 5 fractions per week. The study endpoints were overall survival, progression-free survival, early and late treatment toxicity. Standard and accelerated radiotherapy groups from the study published by Hliniak et al.²⁰ served as controls.

RESULTS

Five-year actuarial overall survival was 87.5% in the study group, 84.5% in the control group receiving accelerated radiotherapy (33 fractions of 2.0 Gy, 6 fractions per week) and 86.2% in the control group (33 fractions of 2.0 Gy, 5 fractions per week). Five-year progression-free survival was 73.6%, 77.2% and 66.2%, respectively. Overall, treatment toxicity and complication rates did not differ between the study group and the control groups.

CONCLUSIONS

The hypofractionated accelerated radiotherapy protocol using 5 fractions per week reduced the use of radiotherapy facilities. There was no significant difference in overall survival and progression-free survival between the study and control groups treated with accelerated or standard radiotherapy.

Comparison between 4-MV and 6-MV radiotherapy in T1N0 glottic cancer

OBJECTIVES/HYPOTHESIS

The purpose of this study was to report the outcomes of a retrospective consecutive cohort study of patients with T1N0M0 glottic carcinoma treated with 4-MV or 6-MV radiotherapy.

STUDY DESIGN

Retrospective case-control study.

METHODS

This was a retrospective review of all patients with T1N0M0 glottic carcinoma treated with radiotherapy between January 2000 and December 2012 in the Department of Radiation Oncology at National Cancer Center Singapore. A total of 124 patients were included. Clinical endpoints of interest were: local control (LC), overall survival (OS), and disease-specific survival (DSS). Other prognostic factors for LC were also analyzed: age, gender, smoking status, T substage, dose fraction, field size, anterior commissure involvement, total dose, and overall treatment time.

RESULTS

Six-megavolt photon radiotherapy was used in 73 patients and 4-MV photon radiotherapy in 51 patients. Median follow-up was 4.9 years. The 5-year LC and OS were as follows: 4 MV, 91.6% and 83.4%; 6 MV, 88.8% and 82.8%; and the 5-year LC, OS, and DSS for all patients were 90.4%, 83.3%, and 98.3%. There was no significant difference in LR and OS between 4-MV and 6-MV radiotherapy (P = .92, P = .16, respectively). In the univariate analysis of LC, none of the prognostic factors was statistically significant. Twenty patients (23%) developed second primary cancers, the majority in the lungs.

CONCLUSIONS

Six-megavolt photon radiotherapy yields comparable results to 4-MV photons. Bolus and computed tomographic simulation are useful to ensure adequate dose coverage of target volume. Follow-up postradiotherapy should incorporate chest imaging, smoking cessation advice, and thyroid function test.

LEVEL OF EVIDENCE

4 Laryngoscope, 127:1061-1067, 2017.

Definitive hypofractionated radiotherapy for early glottic carcinoma: experience of 55Gy in 20 fractions

Introduction

A wide variety of fractionation schedules have been employed for the treatment of early glottic cancer. The aim is to report our 10-year experience of using hypofractionated radiotherapy with 55Gy in 20 fractions at 2.75Gy per fraction.

Methods

Patients treated between 2004 and 2013 with definitive radiotherapy to a dose of 55Gy in 20 fractions over 4 weeks for T1/2 N0 squamous cell carcinoma of the glottis were retrospectively identified. Patients with prior therapeutic minor surgery (eg. laser stripping, cordotomy) were included. The probabilities of local control, ultimate local control (including salvage surgery), regional control, cause specific survival (CSS) and overall survival (OS) were calculated.

Results

One hundred thirty-two patients were identified. Median age was 65 years (range 33–89). Median follow up was 72 months (range 7–124). 50 (38 %), 18 (14 %) and 64 (48 %) of patients had T1a, T1b and T2 disease respectively. Five year local control and ultimate local control rates were: overall - 85.6 % and 97.3 % respectively, T1a - 91.8 % and 100 %, T1b - 81.6 and 93.8 %, and T2 - 80.9 % and 95.8 %. Five year regional control, CSS and OS rates were 95.4 %, 95.7 % and 78.8 % respectively. There were no significant associations of covariates (e.g. T-stage, extent of laryngeal extension, histological grade) with local control on univariate analysis. Only increasing age and transglottic extension in T2 disease were significantly associated with overall survival (both p <0.01). Second primary cancers developed in 17 % of patients. 13 (9.8 %) of patients required enteral tube feeding support during radiotherapy; no patients required long term enteral nutrition. One patient required a tracheostomy due to a non-functioning larynx on long term follow up.

Conclusions

Hypofractionated radiation therapy with a dose of 55Gy in 20 fractions for early stage glottic cancer provides high rates of local control with acceptable toxicity.

Single Vocal Cord Irradiation: Image Guided Intensity Modulated Hypofractionated Radiation Therapy for T1a Glottic Cancer: Early Clinical Results

PURPOSE

To report, from a retrospective analysis of prospectively collected data, on the feasibility, outcome, toxicity, and voice-handicap index (VHI) of patients with T1a glottic cancer treated by a novel intensity modulated radiation therapy technique developed at our institution to treat only the involved vocal cord: single vocal cord irradiation (SVCI).

METHODS AND MATERIALS

Thirty patients with T1a glottic cancer were treated by means of SVCI. Dose prescription was set to 16 × 3.63 Gy (total dose 58.08 Gy). The clinical target volume was the entire vocal cord. Setup verification was done by means of an online correction protocol using cone beam computed tomography. Data for voice quality assessment were collected prospectively at baseline, end of treatment, and 4, 6, and 12 weeks and 6, 12, and 18 months after treatment using VHI questionnaires.

RESULTS

After a median follow-up of 30 months (range, 7-50 months), the 2-year local control and overall survival rates were 100% and 90% because no single local recurrence was reported and 3 patients died because of comorbidity. All patients have completed the intended treatment schedule; no treatment interruptions and no grade 3 acute toxicity were reported. Grade 2 acute dermatitis or dysphagia was reported in only 5 patients (17%). No serious late toxicity was reported; only 1 patient developed temporary grade 2 laryngeal edema, and responded to a short-course of corticosteroid. The VHI improved significantly, from 33.5 at baseline to 9.5 and 10 at 6 weeks and 18 months, respectively (P<.001). The control group, treated to the whole larynx, had comparable local control rates (92.2% vs 100%, P=.24) but more acute toxicity (66% vs 17%, P<.0001) and higher VHI scores (23.8 and 16.7 at 6 weeks and 18 months, respectively, P<.0001).

CONCLUSION

Single vocal cord irradiation is feasible and resulted in maximal local control rate at 2 years. The deterioration in VHI scores was slight and temporary and subsequently improved to normal levels. Long-term follow-up is needed to consolidate these promising results.

Early glottic cancer: role of MRI in the preoperative staging

INTRODUCTION

Clinical staging is the most important time in management of glottic cancer in early stage (I-II). We have conducted a prospective study to evaluate if magnetic resonance imaging (MRI) is more accurate than computed tomography (CT) about tumoral extension, to exactly choose the most appropriate surgical approach, from organ preservation surgery to demolitive surgery. MATERIALS and

METHODS

This prospective study was conducted on 26 male patients, with suspected laryngeal neoplasia of glottic region. The images of MRI and CT were analyzed to define the expansion of glottic lesion to anterior commissure, laryngeal cartilages, subglottic and/or supraglottic site, and paraglottic space. The results of MRI and CT were compared with each other and with the pathology report.

RESULTS

CT accuracy was 70% with low sensitivity but with high specific value. MRI showed a diagnostic accuracy in 80% of cases, with a sensitivity of 100% and high specificity. Statistical analysis showed that MRI has higher correlation than CT with the pathology report.

CONCLUSION

Our study showed that MRI is more sensitive than CT in the preoperative staging of early glottic cancer, to select exactly the eligible patients in conservative surgery of the larynx, as supracricoid laryngectomy and cordectomy by CO2 laser.

Carotid dosimetry for T1 glottic cancer radiotherapy

OBJECTIVE

Radiotherapy for T1 glottic cancer is commonly delivered using a lateral parallel opposed pair of megavoltage photon fields. There is increasing reported evidence of cerebrovascular events due to radiation-induced carotid stenosis. An alternative field arrangement is to use an anterior oblique technique. This study compares the carotid dosimetry between the two techniques and reviews the evidence for the risk of radiation-induced vascular events.

METHODS

The radiotherapy plans of 10 patients with T1 glottic cancer treated with an anterior oblique technique were examined for carotid dose. Alternative plans were then created using a parallel opposed pair of fields and the dose to the carotids compared. All patients received 50 Gy in 16 fractions treating once daily, for 5 days in a week.

RESULTS

The average of the mean dose to the carotids with the anterior oblique technique was 21 Gy compared with 37 Gy using the lateral parallel opposed pair arrangement (p < 0.0001).

CONCLUSION

An anterior oblique field arrangement for the treatment of T1 glottic cancer results in a significantly lower radiation dose to the carotid arteries, which may be clinically important in terms of reducing the risk of cerebrovascular events in long-term survivors.

ADVANCES IN KNOWLEDGE

Although the anterior oblique technique for treating early glottic cancers is well described, and it is predictable that the dose received by the carotid arteries should be lower with this technique, to our knowledge this is the first study to quantify that reduction in dose with a series of patients.

Impact of geometric variations on delivered dose in highly focused single vocal cord IMRT

PURPOSE

To investigate the robustness of single vocal cord intensity modulated radiation therapy (IMRT) treatment plans for set-up errors, respiration, and deformation.

MATERIAL AND METHODS

Four-dimensional computed tomography (4D-CT) scans of 10 early glottic carcinoma patients, previously treated with conventional techniques, were used in this simulation study. For each patient a pre-treatment 4D-CT was used for IMRT planning, generating a reference dose distribution. Prescribed PTV dose was 66 Gy. The impact of systematic set-up errors was simulated by applying shifts of ± 2 mm to the planning CT scans, followed by dose re-calculation with original beam segments, MUs, etc. Effects of respiration and deformation were determined utilizing extreme inhale and exhale CT scans, and repeat scans acquired after 22 Gy, 44 Gy, and 66 Gy, respectively. All doses were calculated using Monte Carlo dose simulations.

RESULTS

Considering all investigated geometrical perturbations, reductions in the clinical target volume (CTV) V95%, D98%, D2%, and generalized equivalent uniform dose (gEUD) were limited to 1.2 ± 2.2%, 2.4 ± 2.9%, 0.2 ± 1.8%, and 0.6 ± 1.1 Gy, respectively. The near minimum dose, D98%, was always higher than 89%, and gEUD always remained higher than 66 Gy. Planned contra-lateral (CL) vocal cord DMean, gEUD, and V40 Gy were 38.2 ± 6.0 Gy, 43.4 ± 5.6 Gy, and 42.7 ± 14.9%. With perturbations these values changed by -0.1 ± 4.3 Gy, 0.1 ± 4.0 Gy, and -1.0 ± 9.6%, respectively.

CONCLUSIONS

On average, CTV dose reductions due to geometrical perturbations were very low, and sparing of the CL vocal cord was maintained. In a few observations (6 of 103 simulated situations), the near-minimum CTV-dose was around 90%, requiring attention in deciding on a future clinical protocol.

An individualised treatment algorithm for tumour stage 1 glottic squamous cell carcinoma

Objective:

To report and discuss the outcome of a treatment algorithm for patients with tumour stage 1 glottic squamous cell carcinoma.

Method:

A retrospective outcome analysis study was performed using data from a tertiary referral centre.

Results:

Sixty-nine patients were treated with radiotherapy and 26 with surgery, in accordance with the treatment algorithm. Five-year overall survival rates were the same for both treatment groups (92 per cent). Five-year disease-specific survival rates were 100 per cent for surgery, 98 per cent for radiotherapy and 99 per cent overall. The overall 5-year laryngeal preservation rate was 89.1 per cent, being 95.7 per cent for surgery patients and 86.7 per cent for radiotherapy patients (p = 0.502). There was no significant association between laryngeal preservation rates and age (p = 0.779), anterior commissure involvement (p = 0.081), tumour stage (1a or 1b) (p = 0.266) or treatment modality (surgery or radiotherapy; p = 0.220). There was no significant difference in local recurrence rates between the two treatment groups (19.3 per cent for radiotherapy vs 10.0 per cent for surgery; p = 0.220). The overall 5-year regional recurrence rate was 1.2 per cent.

Conclusion:

Tumour stage 1 glottic carcinoma can be managed with different treatment modalities, following an individualised treatment algorithm, with results comparable to published outcomes.

Transoral laser surgery versus radiotherapy for tumour stage 1a or 1b glottic squamous cell carcinoma: systematic review of local control outcomes

Background:

Previous literature reviews comparing transoral laser surgery versus radiotherapy for glottic carcinoma treatment have analysed ‘early stage’ disease as one group. The current review aimed to assess local control outcomes, comparing these two treatment modalities, specifically for either tumour stage 1a or stage 1b lesions.

Methods:

The three authors conducted independent, structured literature searches. Simple weighted means were calculated.

Results:

Thirty-six publications were analysed. Three-year local control rates for tumour stage 1a tumours were 88.9 per cent for transoral laser surgery (n = 1308) and 89.3 per cent for radiotherapy (n = 2405). For tumour stage 1b tumours, the local control rates were 76.8 per cent for transoral laser surgery (n = 194) and 86.2 per cent for radiotherapy (n = 492).

Conclusion:

From this analysis of level four evidence, there was no demonstrable difference in local control rates for tumour stage 1a glottic squamous cell carcinoma treated by transoral laser surgery or radiotherapy. There was a trend towards improved local control of tumour stage 1b tumours treated with radiotherapy, but this finding was based on a limited number of published outcomes (n = 194).

Evaluation of acute/late toxicity and local recurrence in T1-T2 glottic carcinoma treated with accelerated hypofractionated 3D-conformal external beam radiotherapy (3D-CRT)

Background

The aim of the study was to evaluate the efficacy, as well as the acute and late toxicity of an accelerated hypofractionated 3DCRT schedule as radical treatment in patients with organ confined glottic cancer cT1-2N0.

Patients and methods.

Between June of 2004 and September 2010, 47 retrospectively selected patients (29 males, 18 females) diagnosed with organ confined T1 or T2 glottic cancer, were treated with external 3DCRT in an accelerated hypofractionation schedule. The median age was 70 years. A dose of 64.4 Gy in 28 daily fractions was prescribed. The primary study endpoints were to assess the acute and late effects of radiation toxicity, according to the EORTC/ RTOG scale, as well as the therapeutic impact of this schedule in terms of local recurrence.

Results

The median follow up was 36 months. At the end of radiotherapy, grade I, II and III acute toxicity was observed in 34, 9 and4 patients, respectively. Late grade I and II toxicity was observed in 25 and in 8 patients respectively. Only two local recurrences were observed, 15 and 24 months post 3DCRT respectively.

Conclusions

Our radiotherapy schedule achieves a high locoregional control rate with the advantage of voice preservation. The proposed hypofractionated schedule can be recommended as a standard radiotherapy treatment, since these results are comparable with those of conventional fractionation schedules.

3D conformal hypofractionated radical radiotherapy in early glottic cancer

AIM

The purpose of this study was to evaluate acute and late toxicity and the locoregional control in patients treated with hypofractionated radical radiotherapy 2.25 Gy/fraction/day for early glottic carcinoma.

MATERIALS AND METHODS

A retrospective analysis was performed of 27 patients, stage T1-T2 N0 glottic squamous cell carcinoma, that underwent radical RT from April 2008 to October 2011. The mean age was 64.6 years (range 36-81). Seventeen patients were staged T1a, 3 patients T1b and 7 patients T2. All patients were 3D planned and treated in a 6 MV LINAC, 2.25 Gy/fraction/5 days per week, to a total dose between 63 Gy and 67.5 Gy. Biological Effective Dose (BED (α/β = 10)) ranged from 77.18 Gy to 82.69 Gy and EQD2 from 64.31 Gy to 68.91 Gy. Patients were evaluated in periodic follow-up. Toxicity was evaluated according to RTOG Toxicities Scales.

RESULTS

With a median follow-time of 24.7 months (range 3.6-44.2 months), no evidence of locoregional recurrence was observed. The treatment was well tolerated and no unscheduled interruptions in treatments for toxicity were documented, with the median overall treatment time of 41 days (range 38-48). Only grades 1 and 2 acute toxicity were observed and no evidence of severe late toxicity.

CONCLUSION

The authors believe that this moderately hypofractionated scheme can provide a good locoregional control for T1-T2 glottic carcinomas with no increase of toxicity. As the limitation of this work is the reduced number of patients and the lack of long term follow-up, the authors hope to update this retrospective study in the future in order to improve the power of the results.

Definitive radiotherapy for T1 glottic squamous cell carcinoma: a 15-year Cruces University Hospital experience

PURPOSE

To evaluate the treatment outcomes for T1 N0 glottic carcinoma after definitive radiotherapy.

METHODS

One hundred and seventeen patients treated with radical radiotherapy from 1990 to 2006 were retrospectively reviewed. The median follow-up duration for the entire group was 92 months (range 4-227). A median dose of 70 Gy (range 63-70 Gy) was administered. We determined the rates of local control (LC), regional control, overall survival (OS) and cause-specific survival (CSS) at 5, 10 and 15 years by Kaplan-Meier product-limit method. The Cox regression analysis was performed to identify significant prognostic factors for LC and survival. The incidence of secondary malignancies is also reported.

RESULTS

The 5-, 10- and 15-year LC rates for the whole group were 84, 80.2 and 80.2 %, respectively. There were 20 local recurrences, of which 19 were salvaged with laryngectomy, giving an ultimate control rate of 90.6 %. The 5-/10-/15-year OS and CSS rates were 81.2 %/66.1 %/48.3 % and 90.6 %/90.6 %/90.6 %, respectively. None of the parameters analyzed exhibited a statistically significant relationship with LC. The age ≥65 years had a statistically significant effect on OS (but not in CSS), with a hazard ratio of 2.45 (95 % confidence interval 1.29-4.66; p = 0.006). During follow-up, 26 patients (22 %) developed a secondary malignancy. Only two patients (1.7 %) presented with severe toxicity (edema and mucositis).

CONCLUSIONS

Radiotherapy alone offers a high likelihood of LC and an excellent CSS rate. In addition, the surgical approach for the salvage is a successful option.

Definitive radiotherapy for early (T1-T2) glottic squamous cell carcinoma: a 20 year Cleveland Clinic experience

Purpose

To report our 20 yr experience of definitive radiotherapy for early glottic squamous cell carcinoma (SCC).

Methods and materials

Radiation records of 141 patients were retrospectively evaluated for patient, tumor, and treatment characteristics. Cox proportional hazard models were used to perform univariate (UVA) and multivariate analyses (MVA). Cause specific survival (CSS) and overall survival (OS) were plotted using cumulative incidence and Kaplan-Meir curves, respectively.

Results

Of the 91% patients that presented with impaired voice, 73% noted significant improvement. Chronic laryngeal edema and dysphagia were noted in 18% and 7%, respectively. The five year LC was 94% (T1a), 83% (T1b), 87% (T2a), 65% (T2b); the ten year LC was 89% (T1a), 83% (T1b), 87% (T2a), and 53% (T2b). The cumulative incidence of death due to larynx cancer at 10 yrs was 5.5%, respectively. On MVA, T-stage, heavy alcohol consumption during treatment, and used of weighted fields were predictive for poor outcome (p < 0.05). The five year CSS and OS was 95.9% and 76.8%, respectively.

Conclusions

Definitive radiotherapy provides excellent LC and CSS for early glottis carcinoma, with excellent voice preservation and minimal long term toxicity. Alternative management strategies should be pursued for T2b glottis carcinomas.

Hypofractionated radiotherapy for T1N0M0 glottic cancer: retrospective analysis of two different cohorts of dose-fractionation schedules from a single institution

AIMS

To determine the influence of dose and fractionation on tumour characteristics, toxicity, disease control and survival outcomes in T1 glottic carcinoma.

MATERIALS AND METHODS

Between 1975 and 2000, treatment charts of 652 patients with T1 glottic carcinoma who received curative radiation with four hypofractionated schedules (50 Gy/15 fractions [3.3 Gy/fraction] or 55 Gy/16 fractions [3.43 Gy/fraction] or 60 Gy/24 fractions or 62.5 Gy/25 fractions [2.5 Gy/fraction]) were analysed. The patients were divided into two groups based on fraction size <3 Gy and >3 Gy. Local control and overall survival were calculated. Patient- and tumour-related factors affecting local control were analysed using univariate and multivariate analysis. Factors affecting late toxicity were also analysed.

RESULTS

The local control and overall survival at 10 years were 84 and 86.1%, respectively, for T1 glottic carcinoma. The response to radiation had a significant effect on local control with univariate analysis (P = 0.001). Other factors, such as beam energy, anterior commissure involvement and fractionation, did not affect local control. Persistent radiation oedema was seen in 123 patients (23.4%) and was significantly worse in patients who received radiation with a larger field size (>36 cm(2)) on a telecobalt machine (P < 0.001).

CONCLUSIONS

Radical radiotherapy schedules incorporating a higher dose per fraction yield acceptable local control rates and late toxicity. Telecobalt therapy for early glottic cancer is a safe alternative to treatment with 6 MV photons on a linear accelerator in terms of local control and late toxicity as long as field sizes smaller than 36 cm(2) are used.