Myxofibrosarcoma of Head and Neck Region - A Rare Case Report.

Myxofibrosarcoma (MFS) is a rare subtype of soft tissue sarcoma that usually occurs in the extremities of the body. Its location in the head and neck region is unique. Surgery is the primary treatment for all non-metastatic MFS. It has high rates of local recurrence and metastasis. Like other soft tissue sarcomas, the aim of adjuvant treatment is to decrease the chances of local recurrence or metastasis in MFS. Due to its rarity, there is a lack of data showing the benefit of adjuvant treatment in MFS of the head and neck region. We are presenting a case report and literature review on MFS in the head and neck.

Effectiveness of Head-and-Neck Molecular Imaging Reporting and Data System Criterion in Head-and-Neck Squamous Cell Carcinoma PostConcurrent Chemoradiotherapy.

Purpose: Postconcurrent chemoradiotherapy (CRT) response assessment has been challenging in locally advanced head-and-neck squamous cell carcinoma (LA-HNSCC) due to prevailing postradiation changes. Molecular response methods have been encouraging, although further clarifications and validations were needed. We tested the effectiveness of a proposed semi-quantitative molecular response criterion in these patients. Materials and Methods: Two subspecialty-trained physicians evaluated 18F-fluorodeoxyglucose positron emission tomography/computed tomography of LA-HNSCC patients (n = 83) post 3 months CRT using a five points Head and Neck Molecular Imaging-Reporting and Data System (HAN-MI-RADS) criterion. Where available, histopathology examination with clinical and imaging interpretation was taken as a reference for the disease. A diagnostic accuracy comparison was done with the existing Hopkins score. Further effectiveness was analyzed with disease-free survival (DFI) and overall survival (OS). Results: Metastasis was developed in 11/83 patients at 3 months of evaluation. Of 72 patients, 39, 2, and 31 patients had a complete response, equivocal response, and partial response as per HAN-MI-RADS. Per patient sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for predicting loco-regional disease up to 1 and 2 years was 93.3%, 92.5%, 90.3%, 94.9%, 92.9%, and 84.9%, 91.9%, 90.3%, 87.2%, and 88.6% respectively. One year and two years DFI for each HAN-MI-RADS score showed a statistically significant difference while it was not for OS. The receiver operating characteristic curve analysis showed significantly better outcome predictability of HAN-MI-RADS (area under the curve [AUC] 0.884) than Hopkins (AUC 0.699). Conclusions: A five points HAN-MI-RADS criterion was found promising for response assessment with less equivocal results and statistically significant higher AUC than Hopkins for loco-regional recurrence prediction.

Treatment Delay during Radiotherapy of Cancer Patients due to COVID-19 Pandemic.

PURPOSE: To analyze the impact of treatment delay caused by COVID-19 infection on patients scheduled for radiotherapy treatment. METHODS AND MATERIALS: In this descriptive study, we analyzed all patients who were COVID-19 positive during the scheduled radiotherapy course, those who had an infection while on neoadjuvant treatment period, or during surgery before the start of radiation. The study period was from June 2020 to May 2021. A treatment delay was defined as a delay in starting the radiation treatment, a gap during their scheduled radiation treatment, or treatment discontinuation. All patients who had a treatment delay were followed-up till November 2021. RESULTS: The median follow-up time of the study was 13 months. Ninety-four patients were selected for the study who met the inclusion criteria. Seventy-seven patients had a mild COVID-19 infection, while 17 had a moderate to severe illness. Of the entire cohort, 83 patients had a treatment delay. The median treatment delay (MTD) in days was 18 (6 to 47). Amongst those who had a treatment delay, 66 patients were treated with curative intent, of which 51 patients are on follow-up - 34 patients are disease-free (MTD - 18.5, 10 to 43), seven had either a residual disease or locoregional recurrence (MTD - 22, 10 to 32), seven had distant metastasis (MTD - 18, 15 to 47), and three patients died (MTD - 20, 8 to 27). Of three patients who died, only one died of COVID-19-related causes. CONCLUSIONS: Even though the mortality due to COVID-19 infection among those who underwent radiotherapy was low, a treatment delay might have caused adverse treatment outcomes. Longer follow-up of these patients is required to further establish this. It will remain debatable whether it was worth delaying radiotherapy for mild to moderate COVID-19 infection for a significant time to cause a potential cancer treatment failure.

Depth of Invasion as an Independent Predictor of Survival in Patients of Stage III Squamous Cell Carcinoma of the Oral Tongue.

OBJECTIVE: Depth of invasion (DOI) has been incorporated in the new AJCC 8th classification. However, even with this new AJCC classification stage III oral tongue squamous cell carcinoma (OTSCC) remains a heterogenous group. The study aims at finding a discreet group within stage III using DOI as a cut-off of 10 mm. METHODS: The institutional database was reviewed from 2012 to 2018 for postoperative stage III OTSCC patients who subsequently received postoperative radiotherapy. Ninety-six patients matched the inclusion criteria. Two groups were created using a DOI cut-off of 10 mm (superficial and deep groups). The groups were analyzed for overall survival (OS) and relapse-free survival (RFS). RESULTS: The baseline and treatment characteristics were comparable between the groups except for the higher number of extensive surgeries, endophytic configuration, pT3 and, DOI in the deep group. For a median follow-up of 40.5 (range: 4-139) months, the median OS and RFS for the superficial group were not reached. The median OS and RFS for the deep group were 101 (range: 73.7-128.3) and 60 (range: 46.6-73.4) months, respectively. The difference was statistically significant for median RFS (P = .008) and trended toward significance for median OS (P = .066) for the superficial group. Multivariate Cox regression analysis showed DOI cut-off as a significant predictor for RFS but not for OS. CONCLUSION: DOI significantly predicts poor RFS. However, showed a trend toward poor OS. This study hints toward a possibility of sub-dividing stage III OTSCC based on DOI cut-off. LEVEL OF EVIDENCE: 3 (Retrospective cohort study) Laryngoscope, 132:1594-1599, 2022.

Role of 68Ga-Prostate-Specific Membrane Antigen PET/CT in Disease Assessment in Glioblastoma Within 48 Hours of Surgery.

Within 48 hours after surgery, disease assessment in glioblastoma is a challenge for both the clinician and the radiologist. Certain technical and logistical issues prevail in this period. Ga-prostate-specific membrane antigen PET/CT is a known molecular imaging marker in prostate cancer. Its role in high-grade gliomas has been recently discussed. We present a case of a 39-year-old man with recurrence glioblastoma of the right frontal lobe and underwent resurgery. After surgery, Ga-prostate-specific membrane antigen PET/CT showed residual disease along the posterior and inferior margin of the postoperative cavity.

Health-related quality of life assessment for head-and-neck cancer patients during and at 3 months after radiotherapy - A prospective, analytical questionnaire-based study.

INTRODUCTION: Health-related quality of life (HRQoL) is a more specific area of QoL that deals with the evaluation and assessment of the impact of the disease and its treatment-related morbidities on a patient's physical, psychological, and social aspects. The aim of the present study was to assess the HRQoL of patients with head-and-neck cancer (HNCs) during and at 3 months after completion of radiotherapy (RT) by intensity-modulated RT. MATERIALS AND METHODS: This study was a prospective, longitudinal, observational, and self-completed questionnaire-based study that included 120 patients with HNC who underwent intensity-modulated RT. The questionnaire had adequate internal consistency. The questionnaires were given to each patient at the beginning of treatment (pretreatment), weekly visits during the course of RT (at the end of 1st, 2nd, 3rd, 4th, 5th, and 6th week), on the day of completion of RT, and then finally at 3 months after completion of RT. Thus, a total of successive nine time points were assessed. RESULTS AND CONCLUSIONS: One hundred and eleven patients completed the questionnaires at all nine time points. HRQoL usually decreases during treatment and then increases to pretreatment levels by 3 months after treatment. The Quality of Life Questionnaire, Core Module and Quality of Life Questionnaire, Head and Neck Module were found to be both valid and reliable. There was a significant QoL reduction for the patients throughout treatment in relation to functions and symptoms in the treatment of HNC. However, all the functions and most of the symptoms returned to baseline at the 3-month follow-up.

Prognostic factors, failure patterns and survival analysis in patients with resectable oral squamous cell carcinoma of the tongue.

PURPOSE: There is sparse literature on treatment outcomes research on resectable oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to measure the treatment outcomes, explore the failure patterns, and identify the potential clinicopathological prognostic factors affecting treatment outcomes for resectable OTSCC. MATERIALS AND METHODS: It is a retrospective analysis of 202 patients with resectable OTSCC who underwent upfront primary surgical resection followed by adjuvant radiotherapy with or without concurrent chemotherapy if indicated. RESULTS: The median follow-up was 35.2 months (range, 1.2 to 99.9 months). The median duration of locoregional control (LRC) was 84.9 months (95% confidence interval, 67.3-102.4). The 3- and 5-year LRC rate was 68.5% and 58.3%, respectively. Multivariate analysis showed that increasing pT stage, increasing pN stage, and the presence of extracapsular extension (ECE) were significantly associated with poorer LRC. The median duration of overall survival (OS) was not reached at the time of analysis. The 3- and 5-year OS rate was 70.5% and 66.6%, respectively. Multivariate analysis showed that increasing pT stage and the presence of ECE were significantly associated with a poorer OS. CONCLUSION: Locoregional failure remains the main cause of treatment failure in resectable OTSCC. There is scope to further improve prognosis considering modest LRC and OS. Pathological T-stage, N-stage, and ECE are strong prognostic factors. Further research is required to confirm whether adjuvant therapy adds to treatment outcomes in cases with lymphovascular invasion, perineural invasion, and depth of invasion, and help clinicians tailoring adjuvant therapy.

Failure patterns of head and neck squamous cell carcinoma treated with radical radiotherapy by intensity modulated radiotherapy technique using focal volume and dosimetric method.

BACKGROUND: Labeling locoregional failures in head and neck cancer (HNC) as "local" and "regional" becomes incomplete when treating with intensity modulated radiotherapy (IMRT). Target delineation and delivery errors, dose in-homogeneity complicate the assessment of failures. A combination of focal point and dosimetric method might attempt at simplifying failure analysis. METHODS: One hundred eleven patients with locally advanced HNC treated with chemoradiation using IMRT were enrolled. Patients with documented failure had their recurrence volume assessed using focal point and dosimetric method. RESULTS: With a median follow-up of 20 (range 0-39) months and median locoregional control (LRC) of 30 (range 24.8-34.5) months, the patients had a 3-year overall survival and LRC of 70.6% and 48.9%, respectively. Of 39 failures, there were 69.2%, 7.6%, 5.1%, 12.8%, and 5.1% type A, B, C, D, and E, respectively using the focal point and dosimetric method. CONCLUSION: With the current classification, majority of the recurrences were high dose failures suggesting inherent radioresistance. While minority of failures were potentially preventable and needed modifying existing IMRT workflow.

Sinonasal teratocarcinosarcoma treated with surgery followed by volumetric modulated radiotherapy: a case report with review of literature.

Surgical excision along with use of postoperative radiotherapy forms an integral management of sinonasal teratocarcinosarcoma (SNTCS). However, given the rarity of the tumor, no standardised guidelines, dose, technique and target delineation exist especially in the era of modern radiation delivery techniques. This is a case of 55-year-old male diagnosed as SNTCS treated with radical ethmoidectomy followed by volumetric modulated radiotherapy, showing good local control and acceptable toxicity profile.

Randomized controlled study comparing simultaneous modulated accelerated radiotherapy versus simultaneous integrated boost intensity modulated radiotherapy in the treatment of locally advanced head and neck cancer.

OBJECTIVES: Comparison of two fractionation schedules of intensity modulated radiotherapy (IMRT) for locally advanced head and neck cancer - simultaneous integrated boost (SIB-IMRT) and simultaneous modulated accelerated radiotherapy (SMART) boost in terms of toxicity and survival end-point measures. PATIENTS AND METHODS: Sixty patients with locally advanced head and neck cancer were randomized in two treatment arms (SIB-IMRT [control arm] and SMART boost arm [study arm]). In the control arm, patients received 70, 63 and 56 Gy in 35 fractions to clinical target volumes (CTV) 1, 2 and 3, respectively. In the study arm, patients received 60 and 50 Gy to CTV 1 and CTV 3, respectively. Toxicities, progression free survival (PFS) and overall survival (OS) were compared between both arms. RESULTS: Baseline patient-related characteristics were comparable between the arms except for primary site of tumour. No significant differences were noted in acute toxicities between the arms except for fatigue which was statistically higher for control arm. No significant differences in 2-year late toxicities were observed. The median follow-up duration was 25.5 (range, 1.8-39.9) months. The 2-year PFS was 53.3% and 80.0% (p = 0.028) for control and study arm, respectively. The 2-year OS was 60.0% and 86.7% (p = 0.020) in control and study arms, respectively. Multivariate analysis showed clinical stage and site to be significant predictors for OS and PFS, respectively. CONCLUSIONS: The SMART boost technique can be a feasible alternative fractionation schedule that reduces the overall treatment time, maintaining comparable toxicity and survival compared with SIB-IMRT.

Prospective study of neoadjuvant chemoradiotherapy using intensity-modulated radiotherapy and 5 fluorouracil for locally advanced rectal cancer - toxicities and response assessment.

AIMS AND OBJECTIVES: The past 2 decades witnessed the strengthening of evidence favoring the role of neoadjuvant chemoradiation (CHRT) in the treatment of locally advanced rectal cancer. The study aims to evaluate the response and acute toxicities to neoadjuvant CHRT using intensity-modulated radiotherapy (IMRT) in the treatment of rectal cancer. Predictive factors to achieve pathological complete response (pCR) were analyzed, as a secondary endpoint. MATERIALS AND METHODS: All consecutive patients who underwent IMRT as part of neoadjuvant CHRT in the treatment of rectal cancer between August 2014 and December 2016 at a tertiary cancer care center were accrued for the study. The cohort underwent CHRT with IMRT technique at a dose of 50.4 Gy in 28 fractions concurrent with continuous infusion of 5 fluorouracil during the first and the last 4 days of CHRT. Surgery was performed 6 weeks later and the pathological response to CHRT was noted. RESULTS: Forty-three subjects were accrued for the study. Radiation dermatitis and diarrhea were the only observed grade ≥3 acute toxicities. Sphincter preservation rate (SPR) was 43.3%. pCR was observed in 32.6%. Univariate and multivariate logistic regression showed that carcinoembryonic antigen was the only independent predictive factor to achieve pCR. CONCLUSION: IMRT as part of neoadjuvant CHRT in the treatment of locally advanced rectal cancer is well tolerated and gives comparable results with respect to earlier studies in terms of pathological response and SPR. Further randomized controlled studies are needed to firmly state that IMRT is superior to 3-dimensional conformal radiotherapy.

Dental Pulp Status of Posterior Teeth in Patients with Oral and Oropharyngeal Cancer Treated with Radiotherapy: 1-year Follow-up.

INTRODUCTION: Teeth may react negatively to pulp sensitivity testing in patients who have undergone radiotherapy. The aim of the current investigation was to evaluate the pulp sensibility of posterior teeth at 4, 6, and 12 months in patients who have undergone radiotherapy for oral and oropharyngeal malignancies. METHODS: Seventy-nine patients diagnosed with malignant oral and oropharyngeal cancer undergoing radiotherapy underwent cold thermal pulp sensitivity testing and electric pulp testing of 4 teeth, 1 from each quadrant. The results were recorded at 5 different time points (TPs): before radiotherapy (TP1), at the end of radiotherapy at 66-70 Gy (TP2), 4 months after the completion of radiotherapy (TP3), 6 months after the completion of radiotherapy (TP4), and 12 months after the completion of radiotherapy (TP5). RESULTS: All 288 teeth tested positive to cold thermal pulp sensitivity testing and electric pulp testing (EPT) at TP1 (100%). No tooth responded to the cold test (100%) at TP4 and TP5, and progressively higher EPT values were noted during the observation period. A statistically significant difference existed in the number of positive responses between different TPs. CONCLUSIONS: There was a progressive decrease in pulp sensibility from TP1 to TP5 in teeth of patients with oral and oropharyngeal cancer who underwent radiotherapy (66-70 Gy). No response to cold thermal tests was noted at TP4 (6 months) and TP5 (12 months), and teeth responded at increasingly higher EPT values from TP1 through TP5. This result was statistically significant.

Cardiac Dose Reduction with Deep-Inspiratory Breath Hold Technique of Radiotherapy for Left-Sided Breast Cancer.

INTRODUCTION: Different techniques of radiation therapy have been studied to reduce the cardiac dose in left breast cancer. AIM: In this prospective dosimetric study, the doses to heart as well as other organs at risk (OAR) were compared between free-breathing (FB) and deep inspiratory breath hold (DIBH) techniques in intensity modulated radiotherapy (IMRT) and opposed-tangent three-dimensional radiotherapy (3DCRT) plans. MATERIALS AND METHODS: Fifteen patients with left-sided breast cancer underwent computed tomography simulation and images were obtained in both FB and DIBH. Radiotherapy plans were generated with 3DCRT and IMRT techniques in FB and DIBH images in each patient. Target coverage, conformity index, homogeneity index, and mean dose to heart (Heart Dmean), left lung, left anterior descending artery (LAD) and right breast were compared between the four plans using the Wilcoxon signed rank test. RESULTS: Target coverage was adequate with both 3DCRT and IMRT plans, but IMRT plans showed better conformity and homogeneity. A statistically significant dose reduction of all OARs was found with DIBH. 3DCRTDIBH decreased the Heart Dmean by 53.5% (7.1 vs. 3.3 Gy) and mean dose to LAD by 28% compared to 3DCRTFB. IMRT further lowered mean LAD dose by 18%. Heart Dmean was lower with 3DCRTDIBH over IMRTDIBH (3.3 vs. 10.2 Gy). Mean dose to the contralateral breast was also lower with 3DCRT over IMRT (0.32 vs. 3.35 Gy). Mean dose and the V20 of ipsilateral lung were lower with 3DCRTDIBH over IMRTDIBH (13.78 vs. 18.9 Gy) and (25.16 vs. 32.95%), respectively. CONCLUSIONS: 3DCRTDIBH provided excellent dosimetric results in patients with left-sided breast cancer without the need for IMRT.

Reirradiation with IMRT for recurrent head and neck cancer: A single-institutional report on disease control, survival, and toxicity.

AIM: To study and explores the feasibility and efficacy of re-irradiation (Re-RT) for locally recurrent head and neck cancer (HNC) and second primary (SP) malignancies. BACKGROUND: The most common form of treatment failure after radiotherapy (RT) for HNC is loco-regional recurrence (LRR), and around 20-50% of patients develop LRR. Re-irradiation (Re-RT) has been the primary standard of care in the last decade for unresectable locally recurrent/SP HNC. MATERIALS AND METHODS: It was a retrospective analysis in which we reviewed the medical records of 51 consecutive patients who had received Re-RT to the head and neck region at our institute between 2006 and 2015. RESULTS: Forty-eight patients were included for assessment of acute and late toxicities, response evaluation at 3 months post Re-RT, and analyses of locoregional control (LRC) and overall survival (OS). The median LRC was 11.2 months, and at 2 and 5 years the LRC rates were 41% and 21.2%, respectively. A multivariate analysis revealed two factors: initial surgical resection performed prior to Re-RT, and achievement of CR at 3 months after completion of Re-RT to be significantly associated with a better median LRC. The median OS was 28.2 months, and at 1, 2, and 5 years, OS were 71.1%, 55.9% and 18%, respectively. A multivariate analysis revealed initial surgical resection performed prior to Re-RT, and achievement of CR at 3 months post completion of Re-RT being only two factors significantly associated with a better median OS. Acute toxicity reports showed that no patients developed grade 5 toxicity, and 2 patients developed grade 4 acute toxicities. CONCLUSION: Re-RT for the treatment of recurrent/SP head and neck tumors is feasible and effective, with acceptable toxicity. However, appropriate patient selection criteria are highly important in determining survival and treatment outcomes.

Comparison between weekly cisplatin-enhanced radiotherapy and cetuximab-enhanced radiotherapy in locally advanced head and neck cancer: first retrospective study in Asian population.

AIM: To present a direct comparison between chemotherapy-enhanced radiotherapy (CERT) and biotherapy-enhanced radiotherapy (BERT) in locally advanced head and neck cancer. METHODS: It is a retrospective analysis of 53 patients with locally advanced head and neck cancer treated from August 2006 to December 2008. For CERT, patients received weekly cisplatin (40 mg/m2 ) and for BERT, a loading dose of 400 mg/m2 of cetuximab given one week prior to radiotherapy followed by 250 mg/m2 given weekly along with radiotherapy. Disease-free survival (DFS) and overall survival (OS) were computed with Kaplan-Meier curve with log-rank test for comparison between the two groups. Multivariate Cox proportional hazards regression analysis was performed to estimate the impact of known relevant prognostic factors on DFS and OS. RESULTS: The median DFS was significantly better with CERT than BERT group (50.82 vs 11.66 months; P = 0.031). The 3 years DFS was significantly higher in CERT group than in BERT group (60.0% vs 14.3%; P = 0.022). The median OS was significantly better with CERT than BERT group (53.61 vs 32.55 months; P = 0.044). The 3 years OS was also significantly higher in CERT group than in BERT group (74.0% vs 42.1%; P = 0.032). There were no significant differences in acute toxicities of all grade and grade ≥3 between the two groups. The compliance to treatment and assisted feeding dependency for more than 6 months duration were also not significantly different. CONCLUSION: CERT is associated with better outcome with no significantly increased acute toxicities compared to BERT.

Dosimetric Comparison between Intensity Modulated Radiotherapy and 3 Dimensional Conformal Radiotherapy in the Treatment of Rectal Cancer

Objective: To compare dosimetric parameters of 3 dimensional conformal radiotherapy (3 DCRT) and intensity modulated radiotherapy (IMRT) in terms of target coverage and doses to organs at risk (OAR) in the management of rectal carcinoma. Methods: In this prospective study, conducted between August 2014 and March 2016, all patients underwent CT simulation along with a bladder protocol and target contouring according to the Radiation Therapy Oncology Group (RTOG) guidelines. Two plans were made for each patient (3 DCRT and IMRT) for comparison of target coverage and OAR. Result: A total of 43 patients were recruited into this study. While there were no significant differences in mean Planning Target Volume (PTV) D95% and mean PTV D98% between 3 DCRT and IMRT, mean PTV D2% and mean PTV D50% were significantly higher in 3 DCRT plans. Compared to IMRT, 3 DCRT resulted in significantly higher volumes of hot spots, lower volumes of cold spots, and higher doses to the entire OAR. Conclusion: This study demonstrated that IMRT achieves superior normal tissue avoidance (bladder and bowel) compared to 3 DCRT, with comparable target dose coverage.

Tumour volumes: Predictors of early treatment response in locally advanced head and neck cancers treated with definitive chemoradiation.

AIM: To analyse and predict early response 3 months post definitive chemoradiation (CCRT) utilising tumour volume (TV) measurement in locally advanced head and neck cancers (LAHNC). BACKGROUND: LAHNC are 3-dimentional lesions. The largest diameter of these tumours measured for T-classification may not necessarily reflect the true tumour dimensions. TV accurately reflects the tumour burden because it is a measurement of tumour burden in all three dimensions. MATERIALS AND METHODS: It is a single institutional prospective study including 101 patients with LAHNC treated with definitive CCRT. TV data noted were primary tumour volume (PTV), total nodal volume (TNV) and total tumour volume (TTV). Response evaluation was done at 3 months after the completion of definitive CCRT and patients were categorised either having achieved complete response (CR) or residual disease. RESULTS: Patients who had not achieved CR were found to have larger TV compared with those who had achieved CR. There were significant inverse correlations between PTV and response (median 16.37 cm(3) vs. 45.2 cm(3); p = 0.001), and between TTV and response (median 36.14 cm(3) vs. 66.06 cm(3); p < 0.001). Receiver operating characteristic (ROC) analysis identified an "optimal cut-off" value of 41 cm(3) for PTV and 42 cm(3) for TTV above and below which the magnitude of difference in response was the greatest. CONCLUSIONS: If response evaluation 3 months post CCRT is to be predicted it is simply not enough to measure the largest single dimension of the tumour. TV seems to be a better and more accurate reflection of the true total tumour burden or extent of the disease.

Dosimetric impact of setup errors in head and neck cancer patients treated by image-guided radiotherapy.

To assess and analyze the impact of setup uncertainties on target volume coverage and doses to organs at risk (OAR) in head and neck cancer (HNC) patients treated by image-guided radiotherapy (IGRT). Translational setup errors in 25 HNC patients were observed by kilovoltage cone beam computed tomography (kV CBCT). Two plans were generated. Plan one - the original plan which was the initially optimized and approved plan of the patient. All patients were treated according to their respective approved plans at a defined isocenter. Plan two - the plan sum which was the sum of all plans recalculated at a different isocenter according to setup errors in x, y, and z-direction. Plan sum was created to evaluate doses that would have been received by planning target volume (PTV) and OARs if setup errors were not corrected. These 2 plans were analyzed and compared in terms of target volume coverage and doses to OARs. A total 503 kV CBCT images were acquired for evaluation of setup errors in 25 HNC patients. The systematic (mean) and random errors (standard deviation) combined for 25 patients in x, y, and z directions were 0.15 cm, 0.21 cm, and 0.19 cm and 0.09 cm, 0.12 cm, and 0.09 cm, respectively. The study showed that there was a significant difference in PTV coverage between 2 plans. The doses to various OARs showed a nonsignificant increase in the plan sum. The correction of translational setup errors is essential for IGRT treatment in terms of delivery of planned optimal doses to target volume.

Dental Pulp Status of Posterior Teeth in Patients with Oral and Oropharyngeal Cancer Treated with Concurrent Chemoradiotherapy.

INTRODUCTION: The absence of tooth sensitivity has been observed in patients who have undergone radiotherapy. The aim of this investigation was to evaluate the effects of concurrent chemoradiotherapy on the pulp status of posterior teeth in patients with malignant oral and oropharyngeal cancer. METHODS: Twenty-one patients diagnosed with malignant oral and oropharyngeal cancer undergoing concurrent chemoradiotherapy underwent cold thermal pulp sensitivity testing and electric pulp testing of 4 teeth, 1 from each quadrant, at 4 points in time (PT): before radiotherapy (PT1), after 30-35 Gy (PT2), at the end of radiotherapy at 66-70 Gy (PT3), and 4 months (PT4) after beginning radiotherapy. RESULTS: All 84 teeth tested positive to cold thermal pulp sensitivity testing at PT1 (100%) and 25 teeth at PT2. No tooth responded at PT3 and PT4 (100%). A statistically significant difference (P < .05) existed in the number of positive responses between different points in time. CONCLUSIONS: Radiotherapy decreased the number of teeth responding to pulp sensitivity testing after doses greater than 30-35 Gy.

Radiation-induced dental caries, prevention and treatment - A systematic review.

Treatment of head and neck cancers (HNCs) involves radiotherapy. Patients undergoing radiotherapy for HNCs are prone to dental complications. Radiotherapy to the head and neck region causes xerostomia and salivary gland dysfunction which dramatically increases the risk of dental caries and its sequelae. Radiation therapy (RT) also affects the dental hard tissues increasing their susceptibility to demineralization following RT. Postradiation caries is a rapidly progressing and highly destructive type of dental caries. Radiation-related caries and other dental hard tissue changes can appear within the first 3 months following RT. Hence, every effort should be focused on prevention to manage patients with severe caries. This can be accomplished through good preoperative dental treatment, frequent dental evaluation and treatment after RT (with the exception of extractions), and consistent home care that includes self-applied fluoride. Restorative management of radiation caries can be challenging. The restorative dentist must consider the altered dental substrate and a hostile oral environment when selecting restorative materials. Radiation-induced changes in enamel and dentine may compromise bonding of adhesive materials. Consequently, glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients. Counseling of patients before and after radiotherapy can be done to make them aware of the complications of radiotherapy and thus can help in preventing them.