Dosimetric Comparison of Four Different Radiotherapy Planning Techniques for Adjuvant Radiotherapy of Left-Sided Breast, Axilla, and Supraclavicular Fossa

Purpose/Aim:

Forward planned intensity-modulated radiotherapy (forward IMRT) with breath-hold (BH) technique is considered optimal by most practitioners for treating left-sided breast cancer. Regional nodal irradiation including axilla and supraclavicular fossa (SCF) increases can increase dose-to-organs at risk (OAR) especially lung. This study was done to assess the potential of inverse planned IMRT (inverse IMRT) to achieve significant reduction in dose to OAR.

Materials and Methods:

Ten patients with left-sided breast cancer treated with Active Breath Co-ordinator BH technique were included in the study. Forward IMRT plans were generated in both BH and free breathing (FB) scans. Inverse IMRT plans were generated in FB scan using Tomotherapy-Direct and Tomotherapy-Helical techniques. Contouring was done as per the ESTRO consensus contouring guidelines. The dose prescribed was 40 Gy in 15 fractions. Statistical significance was tested using one-way ANOVA for parametric data and Kruskall–Wallis test for nonparametric data. Multiple comparison tests were done by using Bonferroni test. P <0.05 was considered to denote statistical significance.

Results:

Inverse IMRT plans achieved superior homogeneity index compared to forward IMRT with BH. Tomotherapy-Direct reduced dose to ipsilateral lung, compared to the forward IMRT with BH while achieving similar doses to other OAR. Tomotherapy-Helical plans achieved significantly better conformity index and reduced maximum dose to left anterior descending artery compared to forward IMRT plans, but low dose to other OAR was significantly worse.

Conclusion:

For left-sided breast, axilla, and SCF radiotherapy, inverse IMRT with Tomotherapy-Direct plan achieved better homogeneity index and reduced dose to ipsilateral lung compared to forward IMRT with BH.

Concurrent chemoradiotherapy for head and neck cancers in older patients: Outcomes and their determinants

INTRODUCTION

Meta-analyses have shown concurrent chemoradiotherapy (CCRT) provides no survival benefit over radiotherapy in patients of head and neck squamous cell carcinoma (HNSCC) aged over 70 years. This study was performed to determine the adverse-effect profile, compliance, functional and oncological outcomes in patients of HNSCC over 70 years of age treated with CCRT.

MATERIALS AND Methods

Retrospective analysis of stage III/IV HNSCC in patients above 70 years of age who received CCRT at our institution (n = 57). Cox-proportional hazards regression model was used for statistical analysis.

RESULTS

There were 57 patients of stage III/IV HNSCC who underwent curative CCRT. 61% completed chemotherapy with no deaths and acceptable toxicity. The predictors of recurrence were poorer performance status (P = 0.031) and treatment breaks (P = 0.04). Tube dependence was associated with 2.7 times higher risk of mortality (P = 0.005).

CONCLUSION

CCRT should be considered standard of care in those over seventy with good performance status. Patients with tube dependence have a higher risk of persistent disease or treatment related mortality.

Nasopharyngeal carcinoma: Experience and treatment outcome with radical conformal radiotherapy from a tertiary care center in India

BACKGROUND AND AIM

The majority of nasopharyngeal carcinoma (NPC) reports on the outcome and prognostic factors are from endemic high-risk regions. Data on the outcome of Indian patients are sparse. In this study, we retrospectively analyzed the outcome of NPC patients treated radically with conformal radiotherapy (RT). The primary objective was to assess the outcome, and the secondary objectives were to assess treatment-related morbidities and the impact of various prognostic factors on the outcome.

MATERIALS AND METHODS

Sixty-eight patients with biopsy-proven NPC who received radical conformal RT, i.e., three-dimensional conformal RT or intensity-modulated RT (IMRT) during 2004-2013 were analyzed. All patients received conformal RT with or without chemotherapy. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS, version 20.0) software, IBM, USA. Survival analysis was performed using Kaplan-Meier method. For calculating the hazard ratio of the prognostic factors, univariate and multivariate Cox regression analyses were done. Chi-square test was used to determine the association.

RESULTS

In this study, with a median follow-up of 43 months, the overall survival (OS), disease-free survival, and cause-specific survival were 91, 85.2, and 98.4% at 2 years and 78.3, 72.8, and 88.2% at 3 years, respectively. The locoregional failure was low (3%), and the 5-year cause-specific survival with chemoradiation was excellent (79%), even with 50% of the patients being nonmetastatic Stage IV. Eleven out of 12 failures were distant metastases. The treatment-related late morbidities were acceptable and better with IMRT. Significant prognostic factors affecting the outcome were composite stage of the disease and the interval between diagnosis and treatment initiation.

CONCLUSION

In locally-advanced NPC, excellent local control is possible with modern conformal RT with concurrent chemotherapy. Distant metastases remain a therapeutic challenge despite systemic chemotherapy. Novel systemic therapies are needed in the future for improving the OS of these patients.

Radical radiotherapy for carcinoma of the larynx in the elderly: Functional and oncological outcomes from a tertiary cancer care center in India

INTRODUCTION

It is estimated that around 10% of all head and neck cancer patients in India are aged over 70 years. Elderly patients are often subjected to palliative or inadequate treatment for head and neck cancers in spite of being candidates for curative intent therapy. In this study we evaluated our use of radical radiotherapy in carcinoma larynx for patients over seventy years of age to determine morbidity, likelihood of completing therapy, functional and oncological outcomes.

MATERIALS AND METHODS

132 patients of squamous cell carcinoma of the larynx treated between 2005-2015 at Amrita Institute of Medical Sciences, Kochi who were seventy years of age or older were included. The endpoint for analysis was overall survival. Survival curves were generated using Kaplan Meier method and univariable analysis was performed using log rank test.

RESULTS

The median age of patients was 77 years (range 70-102). All patients (100%) completed radiotherapy with 6 (5%) requiring treatment breaks. All patients had at least minor (grade I/II) toxicities. Grade III toxicities were seen in 10 (8%) of patients. No grade IV reactions or treatment related deaths occurred. When a univariate analysis was performed for determinants of major toxicities with age range, performance status, smoking, number of co-morbidities or TNM stage, no determinants were statistically significant. 2-year disease free survival for stage I, II, III and IV was 100%, 98%, 80% and 64% respectively, and the 2-year overall survival for all four stages was 100%.

CONCLUSION

Patients over seventy years tolerate radical radiotherapy for treatment of laryngeal cancer. In spite of minor toxicities, all patients completed treatment and had good oncological outcomes. Patients with stage III/IV unfit for concomitant chemotherapy administration treated with radiotherapy alone had a good disease free survival. Curative intent therapy should not be withheld from elderly patients on the basis of age.