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

The outcome of early-stage glottic carcinoma patients treated with radiotherapy: Egyptian National Cancer Institute (NCI-Egypt) experience

Background

Radiotherapy (RT) is an appropriate treatment option for early-stage glottic cancer (ESGC) that achieves high local control and preserves voice quality. However, the optimal radiation treatment schedule remains unknown. We present our institution's 14-year experience in treating ESGC with definitive radiotherapy between 2005 and 2019 inclusively.

Materials and methods

We reviewed the medical records of 104 patients; 63 (60.5%) were treated with conventional fractionation (CF), and 41 (39.5%) were treated with hypofractionated radiotherapy (HF). The clinical T-stage was T1a in 50 patients (48%), T1b in 27 (26%), and T2 in 27 (26%). Age, gender, anterior commissure involvement, stage, radiotherapy technique, radiation fraction size, and overall treatment time (OTT) were analyzed as prognostic factors. The survival outcomes, local regional control (LRC), and laryngeal preservation rate were evaluated.

Results

The 5-year overall survival (OS) and LCR were 83.3% and 78%, respectively. On univariate analysis, treatment with CF (p = 0.02), prolonged OTT > 49 days in CF and > 40 days in HF (p = 0.04), and RT total dose < 66 Gy (p = 0.03) were associated with poor LRC. Multivariate analysis showed a non-significant association with LRC (all p > 0.05). The 5-year OS rate in the CF and HF-treated patients was 84.9% and 72.1%, respectively (p = 0.99), and in patients who had T1a, T1b, and T2 disease, were 78.2%, 96.0%, and 82.1%, respectively (p = 0.43). All patients and tumor variables showed no statistically significant association with OS. Only low-grade acute toxicity was observed.

Conclusion

Non-inferiority results supported the HF schedule to ESGC, including high local disease control and decreased overall treatment time. Our study supports its efficacy in the primary care of ESGC with manageable side effects.

Oncological outcome of vocal cord-only radiotherapy for cT1-T2 glottic laryngeal squamous cell carcinoma

PURPOSE

Early-stage glottic cancer can be treated with radiotherapy only. Modern radiotherapy solutions allow for individualized dose distributions, hypofractionation and sparing of organs at risk. The target volume used to be the entire voice box. This series describe the oncological outcome and toxicity of individualized vocal cord-only hypofractionated radiotherapy for early stage (cT1a-T2 N0).

METHODS

Retrospective cohort study with patients treated in a single center between 2014 and 2020.

RESULTS

A total of 93 patients were included. Local control rate was 100% for cT1a, 97% for cT1b and 77% for cT2. Risk factor for local recurrence was smoking during radiotherapy. Laryngectomy-free survival was 90% at 5 years. Grade III or higher late toxicity was 3.7%.

CONCLUSION

Vocal cord-only hypofractionated radiotherapy appears to be oncologically safe in early-stage glottic cancer. Modern, image-guided radiotherapy led to comparable results as historical series with very limited late toxicity.

Radiomics of dual-energy computed tomography for predicting progression-free survival in patients with early glottic cancer

Aim: This study aimed to predict progression-free survival (PFS) in patients with early glottic cancer using radiomic features on dual-energy computed tomography iodine maps. Methods: Radiomic features were extracted from arterial and venous phase iodine maps, and radiomic risk scores were determined by univariate Cox proportional hazards regression analysis and least absolute shrinkage and selection operator regression with tenfold cross-validation. The Kaplan-Meier method was used to evaluate the association between radiomic risk scores and PFS. Results: Patients were stratified into low-risk and high-risk groups using radiomics, the PFS corresponding rates with statistical significance between the two groups. The high-risk group showed better survival, benefiting from laryngectomy. Conclusion: Radiomics could provide a promising biomarker for predicting the PFS of early glottic cancer patients.

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

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

Prognostic risk factors for initially diagnosed T2N0M0 glottic cancer: competing risk analysis and propensity-score matched cohort analysis

BACKGROUND

Prognostic risk factors of patients with initially diagnosed T2N0M0 glottic cancer remain unclear. This study was aimed to conduct a comprehensive analysis to identify valuable prognostic risk factors for initially diagnosed T2N0M0 glottic cancer.

METHODS

Data of patients with initially diagnosed T2N0M0 glottic cancer were extracted from the Surveillance, Epidemiology, and End Results database. Survival analyses and Cox regression analyses were conducted to evaluate overall survival (OS) and cancer-specific survival (CSS). In consideration of competing events, the competing risk (CR) analysis was applied. Furthermore, propensity-score matching (PSM) was applied to mimic randomized-controlled trials and reduce selection bias.

RESULTS

A total of 923 eligible patients met the inclusion criteria. Survival analyses showed that age, marital status, primary site surgery, and radiation were independent predictors of OS. Besides, age, marital status, primary site surgery, radiation, and chemotherapy were independent predictors of CSS. Cox regression analyses and the CR analysis were basically consistent with this result. In addition, an internal validation and PSM were performed to explore the role of chemotherapy.

CONCLUSION

We conducted a comprehensive analysis to prove that age, marital status, primary site surgery, radiation, and chemotherapy may be valuable prognostic risk factors for initially diagnosed T2N0M0 glottic cancer. Primary site surgery and radiation should be recommended, whereas chemotherapy was likely not suitable so far. Furthermore, we constructed a CR nomogram to predict survival rates.

Early Glottic Cancer Treated by Transoral Laser Surgery Using Toluidine Blue for the Definition of the Surgical Margins: A Pilot Study

Background and objectives: Transoral laser microsurgery (TLM) is widely accepted for its advantages, which consist of a brief hospital stay, rapid functional recovery, low management costs and the fact that it can be easily repeated in cases of recurrence. However, a high incidence of positive or narrow surgical margins has been reported in the literature, even if controversy still exists on the prognostic significance of positive resection margins. The aim of the study was to evaluate the utility of toluidine blue staining in defining the resection margins of early glottic cancer (T1a–T2) treated with TLM. Materials and Methods: This retrospective study was conducted on patients with early glottic cancer (T1a–T2) managed by TLM. A group of patients treated between 2010 and 2014 underwent toluidine blue staining (TB group) of the lesions before starting the cordectomy by TLM, and a group of patients treated by TLM between 2006 and 2009 was considered the control group. Results: A total of 44 subjects were included in this study: 41 were men, and 3 were women. The mean age was 58 ± 9.0 years (median 59.0, range 41–77). Twenty-three of the 44 patients were included in the TB group and 21 in the case control group. In the TB group, only the positivity of the deep margin was a predictor of local recurrence (p = 0.037), while in the control group, positive or close margins and the type of cordectomy were predictive factors of local recurrence (p = 0.049). Considering the TB group and control cases, the 5-year local recurrence-free survival was 95.6% and 80.9%, respectively (p = 0.14). Conclusions: From this first study, toluidine blue staining seems to be a useful modality to improve the rate of the negative resection margins of early glottic cancer (T1a–T2) treated by TLM.