Definitive and adjuvant radiation therapy for external auditory canal and temporal bone squamous cell carcinomas: Long term outcomes.

INTRODUCTION: Primary Squamous Cell Carcinoma (SCC) of the external auditory canal (EAC) and Temporal Bone (TB) are rare entities with very few large reports on outcomes and toxicities. MATERIALS AND METHODS: A retrospective audit of all SCC of EAC/TB tumors treated with curative intent RT at our Institute between January 2007 and December 2019 was undertaken. The primary endpoint of the study was event-free survival (EFS). RESULTS: Eighty-nine patients were eligible for analysis. The median age was 54 years. The median follow-up of surviving patients was 61 months. Sixty-five patients received adjuvant RT, and 24 received definitive RT. Neoadjuvant Chemotherapy for aiding resectability was used in 12 patients, out of which 8 underwent surgery. The 5-year LRC, EFS, and OS were 66.2%, 57.8%, and 63.5%. The predominant pattern of failure was local (n = 36, 40.4%). Regional failure was seen in only five patients, none of which were in patients in whom elective nodal irradiation had been omitted post-operatively. On multivariable analysis adjuvant RT was associated with superior outcomes than definitive RT. Treatment with IMRT resulted in lower ≥ grade 2 late subcutaneous fibrosis (8.7% vs. 38.1%) compared to conventional/3D-CRT technique. CONCLUSIONS: Surgery followed by adjuvant therapy should remain the mainstay of treatment for EAC and TB SCC. IMRT should be the preferred modality for RT due to lower late morbidity. Elective nodal irradiation is routinely not warranted in the adjuvant setting for EAC and TB squamous cell carcinomas.

Quality Improvement Process with Incident Learning Program Helped Reducing Transcriptional Errors on Telecobalt Due to Mismatched Parameters in Different Generations.

Purpose: Higher frequency of transcriptional errors in the radiotherapy electronic charts for patients on telecobalt was noted. We describe the impact of the quality improvement (QI) initiative under the department's incident learning program (ILP). Materials and Methods: The multidisciplinary quality team under ILP was formed to identify the root cause and introduce methods to reduce (smart goal) the current transcription error rate of 40% to <5% over 12 months. A root cause analysis including a fishbone diagram, Pareto chart, and action prioritization matrix was done to identify key drivers and interventions. Plan-Do-Study-Act (PDSA) Cycle strategy was undertaken. The primary outcome was percentage charts with transcriptional errors per month. The balancing measure was "new errors" due to interventions. All errors were identified and corrected before patient treatment. Results: The average baseline error rate was 44.14%. The two key drivers identified were education of the workforce involved and mechanical synchronization of various machine parameters. PDSA cycle 1 consisted of an education program and sensitization of the staff, post which the error rates dropped to 5.4% (t-test P = 0.03). Post-PDSA cycle 2 (synchronization of machine parameters), 1, 3, and 6 months and 1 year, the error rates were sustained to 5%, 4%, 3%, and 4% (t-test P > 0.05) with no new additional errors. Conclusions: With various generations of machines and technologies that are not synchronized, the proneness of transcription errors can be very high which can be identified and corrected with a typical QI process under ILP.

Validation and applicability of para-aortic lymph nodal contouring atlas in cervical cancer.

BACKGROUND AND PURPOSE: CTV delineation guidelines for the para-aortic nodal region for patients with cervical cancer have been proposed (Keenan et al., 2018). The purpose of this study was to validate these guidelines with the use of CT datasets of cervical cancer patients with macroscopic PALN treated with definitive (chemo)radiation (CTRT) at our center. MATERIALS AND METHODS: Planning CT datasets of 71 cervical cancer patients with gross PA nodal disease treated with EFRT were used. Two hundred and two PALN were identified based on size and morphology on diagnostic CECT, PET CT, or histologically proven PALN. LN regions were divided into upper, middle, and lower and based on their relation to the aorta and IVC. Macroscopic PALN were contoured, and the CTV for PALN irradiation was generated based on the proposed guidelines on ECLIPSE (Version 13.5). The centre of mass (COMN) was calculated for each gross PALN. The evaluation was done to review the presence of COMN in relation to the CTV PALN. RESULTS: The most common location of PALN was Left para-aortic (105 LN-52%), Aortocaval (55 LN-27.2%), and Precaval (14 LN-6.9%). Lower PALN were the commonest (104 LN-51.5%). Ninety-three were middle PALN (46%), and 5 were upper PALN (2.5%). After excluding upper PALN, COMN for 11 PALN (5.5%) were outside the CTV while 20 were junctional. CONCLUSION: Our study shows that more than 95% of PALN in this patient cohort were covered using these guidelines with the addition of an extra 5 mm margin laterally on the left.

A Systematic Review of Radiation-Related Lymphopenia in Genito-urinary Malignancies.

BACKGROUND: The impact of radiation-related lymphopenia on clinical outcomes has been reported in various solid malignancies such as high grade gliomas, head and neck cancers, thoracic malignancies and gastro-intestinal malignancies but its impact is not clearly known in the context of common genito-urinary (GU) malignancies. METHODOLOGY: To better understand the effect of radiation-associated lymphopenia in prostate and bladder cancer, we undertook this systematic review of clinical studies that have studied radiation-related lymphopenia in GU malignancies. A systematic methodology search of PubMed, Embase, and Cochrane library resulted in 2125 abstracts. Ten studies fulfilled the inclusion criteria which included any prospective, retrospective study or cohort study of prostate, urinary bladder, kidney, ureter, urethra, penile cancer in humans, and radiation should be part of treatment and intent has to be in definitive or adjuvant settings. Finally the study should have data on radiation-related lymphopenia. RESULTS: Four studies reported on the cancer-specific outcomes related to the lymphopenia. The incidence of low lymphocyte counts were documented in all the studies. Three studies analyzed the factors associated with the Lymphocyte depletion. Pooled incidence of severe lymphopenia was 29.25% and mild to moderate lymphopenia was 60.75%. Bone marrow volume receiving 40 Gy was associated with the incidence of lymphopenia. CONCLUSION: One-third of the patients suffer from severe lymphopenia after radiation in prostate and bladder cancer. There are no clear data to support the correlation between severe lymphopenia and disease outcomes. Bone marrow dosimetry can affect the incidence and severity of lymphopenia. There is need of prospective datasets to identify the impact of radiation-related lymphopenia in GU malignancies focusing on long-term side effects, recurrence rates, and overall survival.

Clinical outcomes for nasopharyngeal cancer with intracranial extension after taxane-based induction chemotherapy and concurrent chemo-radiotherapy in the modern era.

OBJECTIVE: To evaluate the survival outcomes for a cohort of nasopharyngeal cancer with intracranial extension (ICE) treated with induction chemotherapy (ICT) followed by chemo-intensity-modulated radiotherapy (CTRT) at a tertiary cancer center. METHODS: We retrospectively analyzed 45 patients with histologically proven, non-metastatic NPC with ICE treated at our institute between October 2008 and October 2016. Patients were classified as minor ICE or major ICE, based on the extent of ICE. All the patients received 2-3 cycles of a taxane-based ICT regimen followed by CTRT. Radiotherapy was delivered with "risk-adapted" intensity-modulated radiotherapy (IMRT) technique in all patients. RESULTS: After a median follow up of 45 months (range: 8-113 months), the estimated 5-year DFS, LRFS, DMFS, and OS of the entire cohort was 58%, 82%, 67% and 74% respectively. On multivariate analysis, histological subtype was an independent predictor of LRFS, and age was an independent predictor of DFS. The extent of ICE showed only a trend towards worse DFS (P = 0.06). None of the factors significantly predicted for DMFS or OS. Gender, N-stage, and response to ICT did not significantly affect any of the outcomes. Grade 2 or worse subcutaneous fibrosis was seen in 22% of patients and grade 2 or worse xerostomia was seen in 24% of patients at last follow up. Thirty-three percent of the patients developed clinical hypothyroidism at last follow up. None of the patients experienced any neurological or vascular complications. CONCLUSIONS: Taxane-based induction chemotherapy followed by chemo-intensity modulated radiotherapy resulted in excellent locoregional control and survival with acceptable toxicities in patients of nasopharyngeal cancer with intracranial extension. Distant metastasis continues to be the predominant problem in these patients.