Targeting Anterior Commissure Involvement with Hyperfractionated Radiotherapy for T1-T2 Squamous Cell Carcinoma of the Glottic Larynx

Anterior commissure is involved in about 20% of early-stage glottic squamous cell carcinomas (EGSCCs). Treatment outcomes and prognostic factors for EGSCC with anterior commissure involvement (ACI) were evaluated by focusing on hyperfractionated radiotherapy (74.4 Gy in 62 fractions). One-hundred and fifty-three patients with T1-T2 EGSCC were included in this study. The median total doses for T1a, T1b, and T2 were 66, 74.4, and 74.4 Gy, respectively. Overall, 49 (32%) patients had T1a, 38 (25%) had T1b, and 66 (43%) had T2 disease. The median treatment duration was 46 days. The median follow-up duration was 5.1 years. The 10-year overall and cause-specific survival rates were 72% and 97%, respectively. The 10-year local control rates were 94% for T1a, 88% for T1b, and 81% for T2 disease. Local control rates in patients with ACI were slightly better than those in patients without ACI with T1a and T1b diseases; however, the difference was not significant. The 10-year laryngeal preservation rate was 96%. Six patients experienced grade 3 mucositis, and four patients had grade 3 dermatitis. Hyperfractionated radiotherapy was effective for T1 disease with ACI, but insufficient for T2 disease with ACI. Our treatment strategy resulted in excellent laryngeal preservation.

Dosimetric impact of VMAT delivery angles for early glottic cancer treatment

This study investigates the dosimetric effects of different gantry rotation angles used in volumetric modulated arc therapy (VMAT) for early glottic carcinoma. VMAT treatment plans using full-arc, half-arc, and partial-arc gantry rotation angles were generated from 22 computed tomography datasets of early-stage (T1-2N0) glottic laryngeal cancer. Dosimetric parameters associated with the planning target volume (PTV) and organs at risk (OARs), specifically the carotid arteries and thyroid, were compared. To assess the robustness of the VMAT plans, dose variations were analyzed by introducing positional shifts of 1, 3, and 5 mm from the isocenter of each plan along the superior-inferior, left-right, and anterior-posterior axes. Furthermore, we examined the size of the PTV, the air cavity volume within the PTV, and the variability of the beam path length through the gantry angles to investigate their correlations with PTV dose variations in the presence of positioning errors. Compared to full-arc and half-arc plans, the dosimetric parameters of partial-arc plans were found to be higher in PTV (D2%, D5%, D50%, and Dmean) and lower in OARs, while their dose variations of OAR parameters were greater for positioning errors. In addition, a correlation was observed between PTV size and PTV dose variations. Air cavity volume and depth variability were also correlated with some PTV parameters, depending on the arc plan. The results presented in this study suggest that the partial-arc gantry angles can allow higher PTV doses while minimizing OAR doses in VMAT treatment planning for early glottic cancer. However, the small delivery angles may lead to greater dose variations in the OARs when positioning errors occur.

Transoral laser microsurgery for T1 glottic cancer with anterior commissure: Identifying clinical and radiological variables that predict oncological outcome

PURPOSE

The involvement of the anterior commissure (AC) is regarded to be a risk factor for poor results after transoral laser microsurgery (TLM) for early glottic cancer. The objective of this study was to determine how AC-related clinical and radiological factors affected oncological outcomes in a cohort of patients with T1 stage early glottic carcinoma involving the anterior commissure who were treated with TLM with negative surgical margins.

METHODS

Retrospective analysis was performed on clinical, radiological, and follow-up data of patients consecutively treated with TLM at a tertiary academic center between November 2011 and August 2021 for T1 glottic squamous cell carcinoma involving the anterior commissure. Recurrence-free survival (RFS), local control with laser alone (LCL), laryngeal preservation (LP), and overall survival (OS) rates (Kaplan-Meier) were the primary outcome metrics.

RESULTS

In our series, 5-year OS probability was 75.1%, RFS was 64.8%, LCL was 73.8%, and LP was 83.4%. OS and RFS were higher in patients with early stages of AC pattern than in patients with advanced stage (p = 0.004, p = 0.034, respectively). Vertical extension ratio was found to be associated with OS and RFS (p = 0.023, p = 0.001, respectively), and thyroid cartilage interlaminar angle with LCL by multiple Cox regression analysis (p = 0.041).

CONCLUSION

TLM remains a valuable treatment option for AC involvement. AC3 type involvement and elevated vertical extension ratio were associated with negative prognosis. There have been signs that thyroid cartilage with a narrow angle increases recurrence. Alternative modalities should be kept in mind in the treatment decision of these cases.

Case of anterior glottic web with bilateral vocal cord cancers

We experienced a case of anterior glottic web with bilateral vocal cord cancers. The laryngoscopic findings showed milky tumour lesions on bilateral vocal cords and a web-like formation with an adhesion in the anterior commissure. In this case, we performed laryngomicrosurgery to remove the bilateral vocal cord tumours and the anterior glottic web. This case was diagnosed as bilateral glottic carcinoma (laryngeal carcinoma TNM classification: pT1bN0M0) with an anterior glottic web. Therefore, this patient underwent radiation therapy (66 Gy). At present, one and a half years have passed since the end of radiotherapy. There is no recurrence of the glottic cancer or web. The airway at the glottis was patent. It has been reported that cutting-off the anterior glottic web could easily lead to readhesion. Accordingly, we continued to follow-up to determine whether there was a recurrence of readhesion of the anterior glottic web or glottic cancer.

Survival results of 3786 patients with stage I or II laryngeal squamous cell carcinoma: a study based on a propensity score

Introduction

Laryngeal squamous cell carcinoma is the second most prevalent malignancy among head and neck tumors, and the treatment of patients with stage I or II disease can be performed with surgery or radiation therapy. National population studies describing therapeutic results comparing these modalities are unusual, but they can be very important to direct treatment guidelines.

Objective

To evaluate the survival results of patients with laryngeal squamous cell carcinoma at clinical stages I or II, according to the main therapeutic modalities used.

Methods

Cross-sectional, population-based study using the database of Fundação Oncocentro de São Paulo from January 2000 to March 2019. Inclusion criteria were patients with laryngeal squamous cell carcinoma in clinical stages cT1-2N0. To compensate for the non-random allocation of patients and the imbalance between confounding variables between groups, we used the propensity score methodology.

Results

A total of 3786 patients met the inclusion criteria. Regarding the cT stage, there were 2171 patients (57.3%) with cT1 tumors. Patients in the public health system had a longer time between diagnosis and treatment (p < 0.001). The analysis by propensity score showed that patients treated with surgery had a tendency towards better disease-specific survival (p  = 0.012). Comparing radiotherapy alone versus its combination with radiochemotherapy, radiotherapy alone showed a tendency towards a better survival rate (p < 0.001).

Conclusion

Analysis by propensity score identified better results for disease-specific survival in patients with laryngeal squamous cell carcinoma at clinical stages I and II treated by surgery when compared to radiotherapy.

Laser Microsurgery Versus Radiotherapy Versus Open Partial Laryngectomy for T2 Laryngeal Carcinoma: A Systematic Review of Oncological Outcomes

INTRODUCTION

The aim of the current systematic review is to update the pooled survival outcome of patients with T2 glottic carcinoma treated with either laser surgery (CO₂ transoral laser microsurgery [CO₂ TOLMS]), radiotherapy (RT), or open partial laryngectomy (OPL).

METHODS

A systematic search was performed using the MEDLINE database, Scopus, and Google scholar. The inclusion criteria were studies of patients with T2N0 glottic tumor, treated with either primary CO₂ TOLMS, definitive curative RT, or primary OPL, and with reported oncological outcome at 5 years calculated with a Kaplan-Meier or Cox regression method.

RESULTS

The results of the current review show that local control (LC) is higher with OPL 94.4%, while there are no differences in LC at 5-year posttreatment for patients treated with RT, compared to those treated with CO₂ TOLMS (respectively, 75.6% and 75.4%). Primary treatment with OPL and CO₂ TOLMS results in higher laryngeal preservation than primary treatment with RT (respectively 95.8%, 86.9%, and 82.4%).

CONCLUSION

First-line treatment with OPL and CO₂ TOLMS should be encouraged in selected T2 patients, because it results in higher laryngeal preservation and similar LC compared to primary treatment with RT. The involvement of the anterior commissure in the craniocaudal plane and T2b impaired vocal cord mobility have a poorer prognosis and LC compared to patients with T2a tumors for both CO₂ TOLMS and RT.

Oncologic and functional outcomes of transoral CO2 laser cordectomy for early glottic cancer

OBJECTIVE

To investigate the oncological and functional outcomes of the patients treated with transoral CO2 laser cordectomy for early glottic cancer.

PATIENTS AND METHODS

Fifty-five consecutive patients who underwent CO2 laser cordectomy for early glottic cancer were retrospectively reviewed.

RESULTS

Overall survival, larynx preservation, and relapse free local control rates were 96%, 100%, and 91%, respectively. Five patients with local recurrences were salvaged with re-cordectomy and/or radiotherapy. In type I cordectomy, VHI-10 consistently improved during postoperative course and VHI-10 at postoperative 12months was significantly better than preoperative value (2.3 vs. 9.4, p=0.02). Perceptual grading, MPT, MFR and AC/DC also improved and were better than preoperative values. In type III cordectomy, shimmer at 12months after cordectomy was significantly better than preoperative value (14.7 vs. 9.3, p=0.007).

CONCLUSIONS

These results further support the rationale of CO2 cordectomy as initial and salvage surgery for early glottic cancer.

Survival and Prognostic Factors for Outcome after Radiotherapy for T2 Glottic Carcinoma

Background: Local recurrence after radiotherapy for T2 glottic carcinoma remains an issue and identifying patients at risk for relapse is, therefore, important. This study aimed to assess the oncological outcomes and prognostic factors in a consecutive series of patients treated with radiotherapy for T2N0 glottic carcinoma. Methods: Patients with T2N0 glottic carcinoma treated with radiotherapy were included in this retrospective study. Five- and ten-year local control (LC), overall survival (OS), disease-specific survival (DSS), and laryngeal preservation (LP) rates were calculated with the Kaplan–Meier method. The impact of prognostic variables was evaluated with the log-rank test. Results: Ninety-four patients were included for analysis. LC, OS, DSS, and LP rates were 70.5, 63.7, 86.0, and 74.7%, respectively at five years and 65.8, 41.0, 75.6, and 72.4% at 10 years. In total, 46 scans were included in the analyses. Vertical involvement of the anterior commissure on imaging showed a significant impact on LC. Conclusions: In accordance with previously described surgical risk factors, we identified vertical involvement of the anterior commissure on imaging as a prognostic factor for radiation failure.

Prognostic factors in patients with T1 glottic cancer treated with radiotherapy

PURPOSE

Presentation of long-term results of radiation treatment in patients with T1 glottic cancer and evaluation of prognostic factors.

METHODS

We performed a retrospective analysis in a group of 569 patients with T1 squamous cell glottic carcinoma treated with radiotherapy at the Center of Oncology in Cracow between 1977 and 2007. In all, 503 (88%) patients presented with T1a stage disease and 66 (12%) with T1b. Anterior commissure infiltration was present in 179 (31%) patients. Average hemoglobin level prior to therapy was 13.9 g/dl. Using the body mass index (BMI), 114 (20%) patients were underweight, and 91 (16%) were overweight. Median time between collecting tumor specimen and beginning of radiotherapy was 56 days (range 14-145 days). Treatment regimen was normofractionated with single fraction ≤2 Gy in 102 (18%) and hypofractionated in 467 (82%) patients.

RESULTS

The 5‑ and 10-year overall survival (OS), disease-specific survival (DSS) and local control (LC) rates were 85 and 68%, 88 and 86%, 89 and 87%, respectively. Multivariate analysis showed that tobacco smoking, low hemoglobin level (<13 g/dl), anterior commissure infiltration, fraction dose ≤2 Gy and time from collecting specimen to beginning of therapy longer than 30 days had negative impact on LC and DSS. Patients' age over 60 years, worse performance status and malnutrition (BMI <18.5) had negative impacts on OS.

CONCLUSIONS

Radiotherapy is a highly effective treatment method in patients with T1N0M0 glottic cancer. LC and DSS may be improved following hypofractionation, smoking cessation, and shortening of waiting-time until start of treatment. OS was mainly influenced by nutritional and performance status.

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.

The Treatment of Laryngeal Cancer

Successful management of laryngeal cancer depends on careful pretreatment evaluation of patient and disease factors to arrive at accurate staging, leading to appropriate treatment selection for patients with this highly impacting disease. Surgical modalities, including transoral laser microsurgery, open partial laryngectomy, and total laryngectomy, offer options, alone or in combination with radiation and chemotherapy. Treatment strategy for laryngeal cancer should strive for cure while maintaining the best quality of life possible for the patient. Achieving the goals of initial and salvage treatment for laryngeal cancer depends on executing a plan of care determined by the expertise of the multidisciplinary team.

Oncologic and functional outcomes of patients treated with transoral CO2 laser microsurgery or radiotherapy for T2 glottic carcinoma: a systematic review of the literature

PURPOSE OF REVIEW

To give an overview of the laryngeal preservation and functional outcomes of patients treated with transoral CO2 laser microsurgery (TLM) or radiotherapy for T2 glottic carcinoma. This information supports physicians and patients in treatment counselling and choices.

RECENT FINDINGS

A recent systematic review showed that local control rates at 5-year did not differ between radiotherapy and TLM for T2 glottic tumours. However, there is a lack of comparative data on laryngeal preservation as well as functional outcomes in T2 glottic carcinoma.

SUMMARY

Laryngeal preservation for T2 tumours in this review is higher for patients treated primarily with TLM (88.8 vs. 79.0%). It is important to differentiate between tumours with normal and impaired mobility (T2a and T2b) because the latter showed poorer prognosis for both TLM and radiotherapy. Involvement of the anterior commissure does not result in significantly lower oncological results, if adequately staged and treated. More studies are needed to support these data and to compare the functional outcomes between TLM and radiotherapy for T2 glottic carcinoma.

Use of Larynx-Preservation Strategies in the Treatment of Laryngeal Cancer: American Society of Clinical Oncology Clinical Practice Guideline Update

Purpose To update the guideline recommendations on the use of larynx-preservation strategies in the treatment of laryngeal cancer. Methods An Expert Panel updated the systematic review of the literature for the period from January 2005 to May 2017. Results The panel confirmed that the use of a larynx-preservation approach for appropriately selected patients does not compromise survival. No larynx-preservation approach offered a survival advantage compared with total laryngectomy and adjuvant therapy as indicated. Changes were supported for the use of endoscopic surgical resection in patients with limited disease (T1, T2) and for initial total laryngectomy in patients with T4a disease or with severe pretreatment laryngeal dysfunction. New recommendations for positron emission tomography imaging for the evaluation of regional nodes after treatment and best measures for evaluating voice and swallowing function were added. Recommendations Patients with T1, T2 laryngeal cancer should be treated initially with intent to preserve the larynx by using endoscopic resection or radiation therapy, with either leading to similar outcomes. For patients with locally advanced (T3, T4) disease, organ-preservation surgery, combined chemotherapy and radiation, or radiation alone offer the potential for larynx preservation without compromising overall survival. For selected patients with extensive T3 or large T4a lesions and/or poor pretreatment laryngeal function, better survival rates and quality of life may be achieved with total laryngectomy. Patients with clinically involved regional cervical nodes (N+) who have a complete clinical and radiologic imaging response after chemoradiation do not require elective neck dissection. All patients should undergo a pretreatment baseline assessment of voice and swallowing function and receive counseling with regard to the potential impact of treatment options on voice, swallowing, and quality of life. Additional information is available at www.asco.org/head-neck-cancer-guidelines and www.asco.org/guidelineswiki .

Guidelines for the Surgical Management of Laryngeal Cancer: Korean Society of Thyroid-Head and Neck Surgery

Korean Society of Thyroid-Head and Neck Surgery appointed a Task Force to develop clinical practice guidelines for the surgical treatment of laryngeal cancer. This Task Force conducted a systematic search of the EMBASE, MEDLINE, Cochrane Library, and KoreaMed databases to identify relevant articles, using search terms selected according to the key questions. Evidence-based recommendations were then created on the basis of these articles. An external expert review and Delphi questionnaire were applied to reach consensus regarding the recommendations. The resulting guidelines focus on the surgical treatment of laryngeal cancer with the assumption that surgery is the selected treatment modality after a multidisciplinary discussion in any context. These guidelines do not, therefore, address non-surgical treatment such as radiation therapy or chemotherapy. The committee developed 62 evidence-based recommendations in 32 categories intended to assist clinicians during management of patients with laryngeal cancer and patients with laryngeal cancer, and counselors and health policy-makers.

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.