Is there any radiation-induced brachial plexopathy after hypofractionated postmastectomy radiotherapy with helical tomotherapy?

Introduction: Radiation-induced brachial plexopathy (RIBP) is one of the most concerning late radiation effects after hypofractionated postmastectomy radiotherapy (HF-PMRT) to the chest wall and regional lymph nodes. The purpose of this study was to investigate the RIBP events occurring in breast cancer patients after HF-PMRT using intensity-modulated radiation therapy (IMRT) by helical tomotherapy. Furthermore, the dosimetric parameters of the ipsilateral brachial plexus were reported. Materials and methods: Breast cancer patients who underwent HF-PMRT using the IMRT via HT at our institute were included. In the first cohort, subjective RIBP symptoms were measured using a QuickDASH questionnaire, whereas objective RIBP events were assessed using a comprehensive physical evaluation in the second cohort. The ipsilateral brachial plexus from all eligible patients' treatment plans was contoured, and the dosimetric parameters were explored. Results: From March 2014 to December 2022, 229 patients were enrolled; 107 and 72 individuals were in the first and second cohorts, respectively. The first cohort's median follow-up period was 27 months, and the second cohort was 31 months. In the first cohort, 80 patients (74.77%) had a normal function, 21 (19.63%) had a mild grade, and 6 (5.61%) had a moderate grade; no severe or very severe RIBP was observed. However, the comprehensive physical evaluation of the second cohort indicated no RIBP events. Dosimetric analysis revealed that the median maximum dose was 44.52, 44.52, and 44.60 Gy; the median mean dose was 33.00, 32.23, and 32.33 Gy; and the median dose at 0.03 cc was 44.33, 44.36, and 44.39 Gy for all patients, patients in the first and second cohort, respectively. Each dosimetric parameter was evaluated, and no statistically significant differences were detected. Conclusion: The absence of RIBP events supports the safety of employing HF-PMRT by HT for the chest wall and all regional lymph nodes. We propose that applying the ICRU Report 83 criteria for IMRT planning, which limit the maximum dose (107% of the prescribed dose) to less than 2% of the planning target volume and exclude the brachial plexus region from the maximal dose area, is a practical way to minimize the risk of RIBP from HF-PMRT.

Retrospective Analysis of All Types of Adjuvant Radiotherapy in Endometrial Cancer: Single-Center Experiences in a Middle-Income Country.

OBJECTIVE: We retrospectively analyzed the efficacy, focusing on overall survival (OS) and the patterns of failure, along with the toxicities of adjuvant radiotherapy (RT) in endometrial cancer patients. METHODS: Two-hundred and nineteen patients with endometrial cancer patients who received adjuvant radiotherapy ± adjuvant chemotherapy (ACT) from January 2014 to December 2018 were investigated for overall survival (OS), local recurrence-free survival rate (LRFS), regional recurrence-free survival rate (RRFS), and distant metastasis-free survival rate (DMFS). RESULT: Two-hundred and fourteen patients were evaluated. The numbers of VBT alone, EBRT plus VBT, and adjuvant chemotherapy (ACT) plus EBRT plus VBT were 65 (30.4%), 80 (37.4%), and 69 (32.2%) patients, respectively. Stage I (107 patients) was the most common followed by stage III (87 patients). With a median follow-up time of 67 months (IQR 56-78), the 5-year overall survival rates for VBT alone, EBRT plus VBT, and EBRT plus VBT plus ACT were 84.4%, 65%, and 57.4%, respectively. The most common severe (grade 3-4) acute toxicity was neutropenia (4.6%), followed by diarrhea (3.7%). Grade 3-4 late proctitis was found in only 1.9%. On multivariate analysis, advanced age (HR 6.15, p: 0.015), lymph node involvement (HR 6.66, p: 0.039), cervical involvement (HR 10.60, p: 0.029), and substantial LVSI (HR 21.46, p: 0.005) were associated with a higher risk of death. CONCLUSION: Advanced age (>65), substantial LVSI, lymph node involvement, and cervical stromal involvement were associated with poor overall survival. These findings here will help identifying high-risk patients and would make it possible to avoid unnecessary adjuvant treatment among patients with a good prognosis.

Hypofractionated whole breast irradiation with simultaneous integrated boost in breast cancer using helical tomotherapy with or without regional nodal irradiation: A report of acute toxicities.

Purpose: We prospectively investigated the acute toxicities focusing on skin and hematologic function in breast cancer patients who received hypofractionated whole breast irradiation with simultaneous integrated boost (HF-WBI-SIB) with helical tomotherapy (HT), with or without regional nodal irradiation (RNI). Methods: The dose of WBI and RNI was 42.4 Gy in 16 fractions. Tumor bed was prescribed to 49.6 Gy in 16 fractions simultaneously. The association between the worst grade of acute toxicities during treatment and receiving RNI was analyzed. The integral dose to the whole body between the two groups was also compared. Results: Between May 2021 and May 2022, 85 patients were enrolled; 61 patients received HF-WBI-SIB only (71.8%) and 24 patients (28.2%) received HF-WBI-SIB with RNI. Grade 2 acute skin toxicity was found in 1.2%. The most frequent grade 2 or more hematologic toxicity was leukopenia, which occurred in 4.8% and 11% in the 2nd and 3rd week, respectively. Mean whole body integral dose was significantly higher in patients treated with RNI compared to patients treated without RNI: 162.8 ± 32.8 vs. 120.3 ± 34.7 Gy-L (p-value < 0.001). There was no statistically significant difference in acute grade 2 or more skin and hematologic toxicities between the two groups. Conclusions: HF-WBI-SIB with or without RNI is feasible with acceptable acute skin and hematologic toxicities. RNI and whole body integral dose were not associated with these acute toxicities.

Development of a quality assurance system in radiation oncology: A 12-year experience in a University Hospital.

PURPOSE: This study aimed to report 12 years of experience in the development of a quality assurance system in radiation oncology in a university hospital. MATERIAL AND METHODS: We developed the Quality Assurance Program in Radiation Oncology (QUAPRO) in 2008 to detect treatment deviation in the radiotherapy (RT) process with three steps of near-miss detection: simulation and prescription (primary check, PC), treatment planning (secondary check, SC), and treatment delivery process (tertiary check, TC). We transferred our paper-based medical records to electronic-based radiotherapy information systems (RTISs) in 2013. QUAPRO was completely integrated into RTIS in 2017. Since then, electronic-based incident reporting has been conducted. The program is called the Radiation Incident Learning System (RILS). The near-miss rates were compared during the three time periods: 2008-2012, 2013-2017, and 2017-2020. RESULTS: Five years of paper-based QUAPRO for 2008-2012 demonstrated a fluctuation in the checking ratio, with a gradually increasing rate of near misses of 3.5-19.7%. After electronic-based medical records were developed in 2013, the results revealed a dramatic increase from a rate of 2.7 to 4.2 in the number of checks per patient and achieved an increased rate of near misses of 24.7% for PC, SC, and TC. The rate of near misses gradually decreased to 5.3% after 2017 because of RT workflow improvement. CONCLUSION: The analysis of 12 years in near-miss data reflected the effectiveness of our quality assurance program. The QUAPRO system can detect near-miss incidents in the whole RT workflow and illustrate the detection improvement when integrated into electronic-based medical records. Regular feedback and exploration of near-miss reporting are recommended for proper RT workflow improvement.

Breast Cancer Subtypes in Northern Thailand and Barriers to satisfactory survival outcomes.

BACKGROUND: The incidence of breast cancer (BC) in Thailand has been rising at an alarming rate. The annual incidence of BC in Thailand has doubled over a span of 15 years. A retrospective study was conducted with the primary objective of assessing and comparing survival rates of patients with BC, stratified by subtype of BC. METHODS: A retrospective study was implemented for a cohort of women receiving a diagnosis of invasive BC with the objective of assessing and comparing their overall survival, stratified by BC subtype. Thai women receiving a diagnosis of their first primary invasive BC between January 2006 and December 2015 at Chiang Mai University Hospital were studied with 3,150 cases meeting the eligible criteria. RESULTS: The median follow-up time was 4.9 years (Inter Quartile Range: 2.8-7.7). The most common diagnosed subtype was luminal B-like (n = 1,147, 36.4%). It was still the most prevalent subtype (35.8%) in women younger than 40 years and the 40-60 age-group, The proportion of patients with TNBC is the highest in women aged less than 40 years with 19.3% compared to the other age categories. Finally, among women older than 60 years, the proportion of each subtype was relatively uniform. Most women received a diagnosis of stage II disease. Triple negative subtype increased overall mortality in advanced staging (stages III and IV) (aHR:1.42, 95% CI: 0.96-2.11). The 5-year overall survival rate was found in luminal A-like at 82.8%, luminal B-like at 77.6%, HER-2 enriched at 66.4% and triple negative subtype at 64.2%. CONCLUSION: The histologic subtype, correlated with age and staging influenced the OS. Our results confirmed the association of triple negative BC with poor prognosis especially in advanced stage. The adjuvant medical treatment in our country could not be accessible in some group of patients, so the results of treatment and survival especially HER-2 enriched are lower than other countries without treatment barrier.

Brachytherapy dose changes: comparing in-room and out-room image-guided brachytherapy. A randomized study.

Purpose: Image-based brachytherapy, involving an image machine and a brachytherapy unit in the same room (in-room brachytherapy [IRBT]), limits patient movements; however, this technique may not be feasible in high workload centers. In this study, we compared changes in the dose and volume of organs at risk (OARs) with out-room brachytherapy (ORBT) technique, in which patients musted be transferred to a waiting room and then transferred back for brachytherapy delivery. Material and methods: This was a randomized prospective study comparing changes in D2cc doses and volume of OARs during IRBT and ORBT. Patients underwent CT for treatment planning (CT1) installed in brachytherapy loading room, and another CT immediately before brachytherapy (CT2) during each fraction. While patients remained on CT table after CT1 during treatment planning and delivery in IRBT arm, they were transferred out to waiting room and back to CT table in ORBT arm. CT2 was analyzed with CT1 to evaluate any changes in volumes and doses. Results: A total of 294 fractions of brachytherapy were considered. The findings indicated no significant differences in the mean D2cc changes (Gy) (CT2 minus CT1) to the bladder, rectum, and sigmoid between IRBT and ORBT (mean ±SD: -0.07 ±0.36 vs. -0.01 ±0.39, p = 0.1426; -0.15 ±0.32 vs. -0.14 ±0.29, p = 0.8898; -0.17 ±0.38 vs. -0.19 ±0.31, p = 0.5221, respectively). Moreover, significant correlations were observed between D2cc changes and volume changes to each of OARs, p < 0.001. Conclusions: IRBT does not result in differences in dose changes between planning and pre-treatment imaging when compared with ORBT. Consequently, ORBT can be considered for routine practice in high workload centers. Correlations in volume change and dose change to OARs were also observed.

Health Effects of Natural Environmental Radiation during Burning Season in Chiang Mai, Thailand.

This paper presents the first measurement of the investigation of the health impacts of indoor radon exposure and external dose from terrestrial radiation in Chiang Mai province during the dry season burning between 2018 and 2020. Indoor radon activity concentrations were carried out using a total of 220 RADUET detectors in 45 dwellings of Chiang Mai (7 districts) during burning and non-burning seasons. Results show that indoor radon activity concentration during the burning season (63 ± 33 Bq/m3) was significantly higher (p < 0.001) compared to the non-burning season (46 ± 19 Bq/m3), with an average annual value of 55 ± 28 Bq/m3. All values of indoor radon activity concentration were greater than the national (16 Bq/m3) and worldwide (39 Bq/m3) average values. In addition, the external dose from terrestrial radiation was measured using a car-borne survey during the burning season in 2018. The average absorbed rate in the air was 66 nGy/h, which is higher than the worldwide average value of 59 nGy/h. This might be due to the high activity concentrations of 238U and 323Th in the study area. With regards to the health risk assessment, the effective dose due to indoor radon exposure, external (outdoor) effective dose, and total annual effective dose were 1.6, 0.08, and 1.68 mSv/y, respectively. The total annual effective dose is higher than the worldwide average of 1.15 mSv/y. The excess lifetime cancer risk and radon-induced lung cancer risk during the burning season were 0.67% and 28.44 per million persons per year, respectively. Our results substantiate that indoor radon and natural radioactive elements in the air during the burning season are important contributors to the development of lung cancer.

Survival outcome of cervical cancer patients treated by image-guided brachytherapy: a 'real world' single center experience in Thailand from 2008 to 2018.

The objective of our study was to evaluate the survival outcome of cervical cancer patients treated using image-guided brachytherapy (IGBT). From 2008 to 2018, 341 patients with cervical cancer were treated by radical radiotherapy. IGBT (by computed tomography [CT] or transabdominal ultrasound [TAUS]) was used to treat all of these patients. The characteristic data and patient status after treatment were recorded. All data were evaluated for survival outcome analysis. From a total of 341 patients, 295 patients were analyzed and 46 patients were excluded due to data missing in the survival outcomes. At the median follow-up time of 48 months (IQR 30-80 months), The 4-year local control, progression-free survival and overall survival rates were 89.5%, 74.9% and 69.1%, respectively. For overall survival, the size (> 5 cm), pathology (non-SCCA), stage (stage III-IV by FIGO 2009), lymph node (LN) (presented) and overall treatment time (OTT) (> 56 days) showed statistical significance in univariate analysis while non-SCCA pathology, advanced stage, presented LN and longer OTT showed statistical significance in multivariate analysis. In conclusion, our analysis reports a 4-year overall survival rate of 69.1%. Non-SCCA pathology, advanced stage disease, LN presence and longer OTT showed worse prognostic factors in multivariate analysis.

Stereotactic radiosurgery for limited brain metastasis using three different techniques: helical tomotherapy, volumetric modulated arc therapy, and cone-based LINAC radiosurgery.

PURPOSE: Specific radiation delivered to tumors by stereotactic radiosurgery (SRS) has become widely used in the treatment of brain metastasis. This study aimed to compare radiation therapy planning and its parameters from SRS using three different modalities: helical tomotherapy (HT), volumetric modulated arc therapy (VMAT), and cone-based linac radiosurgery (Cone-based). MATERIALS AND METHODS: Each contouring dataset of patents who experienced one to four brain metastasis received SRS in our center was re-planned to create radiation therapy planning in all three treatment systems (HT, VMAT, and Cone-based). The parameters of conformity index (CI), homogeneity index (HI), CI50, and gradient index (CGI) were analyzed to compare the effects of the three techniques. Decision score analysis was used to evaluate the performance on dosimetric and organs-at-risk parameters among the different techniques by applying the Cone-based technique as a benchmark. RESULTS: A total of 21 patients with 39 lesions were included in this study. The results from the decision score analysis demonstrated statistically identical CI, CI50, and CGI values between Cone-based and VMAT for single lesions. For multiple lesions, VMAT also provided better CI when compared to Cone-based technique while HT exhibited the poorest dosimetric parameters. Moreover, VMAT exhibited the lowest BrainV5Gy value and displayed the shortest beam-on time calculation. CONCLUSION: We have conducted a comprehensive comparison of SRS planning approaches. The Cone-based technique revealed the highest HI value, while VMAT provided the best estimated beam-on time value. HT displayed a feasible SRS modality for single lesions, but not for multiple lesions.

A Potential Serum Biomarker for Screening Lung Cancer Risk in High Level Environmental Radon Areas: A Pilot Study.

Radon is a major cause of lung cancer (LC) deaths among non-smokers worldwide. However, no serum biomarker for screening of LC risk in high residential radon (HRR) areas is available. Therefore, the aim of this study was to determine diagnostic values of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (Cyfra21-1), human epididymis protein 4 (HE4), interleukin 8 (IL-8), migration inhibitory factor (MIF), tumor nuclear factor-alpha (TNF-α) and vascular endothelial growth factors (VEGF) occurring in high radon areas. Seventy-five LC non-smoker patients and seventy-five healthy controls (HC) were enrolled in this study. Among the HC groups, twenty-five HC were low residential radon (LRR) and fifty HC were HRR. Significantly higher (p < 0.0004) serum levels of CEA, Cyfra21-1, IL-8 and VEGF were found in the LC compared with the LRR and HRR groups. More importantly, significantly higher levels (p < 0.009) of serum CEA, Cyfra21-1 and IL-8 were observed in HRR compared with the LRR group. Likewise, a ROC curve demonstrated that serum CEA and Cyfra21-1 could better distinguish LC risk from HRR groups than IL-8. These results indicated that serum CEA and Cyfra21-1 were significantly increased in the HRR group and may be considered as potential biomarkers for individuals at high-risk to develop LC.

The advantages of abdominal compression with shallow breathing during left-sided postmastectomy radiotherapy by Helical TomoTherapy.

BACKGROUND: Left-sided post-mastectomy radiotherapy (PMRT) certainly precedes some radiation dose to the cardiopulmonary organs causing many side effects. To reduce the cardiopulmonary dose, we created a new option of the breathing adapted technique by using abdominal compression applied with a patient in deep inspiration phase utilizing shallow breathing. This study aimed to compare the use of abdominal compression with shallow breathing (ACSB) with the free breathing (FB) technique in the left-sided PMRT. MATERIALS AND METHODS: Twenty left-sided breast cancer patients scheduled for PMRT were enrolled. CT simulation was performed with ACSB and FB technique in each patient. All treatment plans were created on a TomoTherapy planning station. The target volume and dose, cardiopulmonary organ volume and dose were analyzed. A linear correlation between cardiopulmonary organ volumes and doses were also tested. RESULTS: Regarding the target volumes and dose coverage, there were no significant differences between ACSB and FB technique. For organs at risk, using ACSB resulted in a significant decrease in mean (9.17 vs 9.81 Gy, p<0.0001) and maximum heart dose (43.79 vs 45.45 Gy, p = 0.0144) along with significant reductions in most of the evaluated volumetric parameters. LAD doses were also significantly reduced by ACSB with mean dose 19.24 vs 21.85 Gy (p = 0.0036) and the dose to 2% of the volume (D2%) 34.46 vs 37.33 Gy (p = 0.0174) for ACSB and FB technique, respectively. On the contrary, the lung dose metrics did not show any differences except the mean V5 of ipsilateral lung. The positive correlations were found between increasing the whole lung volume and mean heart dose (p = 0.05) as well as mean LAD dose (p = 0.041) reduction. CONCLUSIONS: The ACSB technique significantly reduced the cardiac dose compared with the FB technique in left-sided PMRT treated by Helical TomoTherapy. Our technique is uncomplicated, well-tolerated, and can be applied in limited resource center.

Comparison of clinical outcomes achieved with image-guided adaptive brachytherapy for cervix cancer using CT or transabdominal ultrasound.

PURPOSE: This study aimed to evaluate retrospectively the treatment results when using various image-guided adaptive brachytherapy treatments for cervical cancer treated by radical radiotherapy. METHODS AND MATERIALS: From 2014 to 2017, 188 patients with cervical carcinoma were treated by whole pelvic radiotherapy plus four fractions of image-guided brachytherapy. Eight patients were excluded because of missing data. Consequently, 180 patients were analyzed. Of 180 patients, 92 were treated by CT-based brachytherapy (CT-BT), and transabdominal ultrasound-based brachytherapy (TAUS-BT) was used to treat another group. The treatment results and toxicity outcomes were evaluated by comparing the image-guidance techniques. RESULTS: The mean follow-up time was 32 months (interquartile range 29.5-42 months). The mean age was 57 years (interquartile range from 50 to 65 years). In the CT-BT group, the mean cumulative doses to high-risk clinical target volume, bladder, rectum, and sigmoid were 87.2 Gy, 84.0 Gy, 68.8 Gy, and 69.8 Gy, respectively. In the TAUS-BT group, the mean cumulative doses to the cervix reference, bladder, and rectum points were 84.0 Gy, 65.5 Gy, and 74.0 Gy, respectively. There were no differences in the 2-year local control rate (p = 0.88) and disease-free survival rate (p = 0.34) in both groups. No difference in gastrointestinal and genitourinary toxicity was observed in both groups, but there was higher vaginal toxicity in the TAUS-BT group compared with the CT-BT group (p = 0.03). CONCLUSIONS: No difference in treatment results was observed between CT-based and TAUS-based approaches. However, TAUS-BT had higher vaginal toxicity in our retrospective analysis.

Analysis of the planned, delivered dose distributions and quality assurance for helical tomotherapy and volumetric modulated arc therapy in locally advanced non-small cell lung cancer.

BACKGROUND: With full access to both helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT), we compared locally advanced non-small cell lung cancer (LA-NSCLC) treatment plans and verified the plans using patient-specific pretreatment quality assurance (PSQA). MATERIALS AND METHODS: For each of the seventeen patients included in the study, two treatment plans (i.e. HT and VMAT) were created. Optimized plans were evaluated following the ICRU 83 criteria. Planned quality indexes and dosimetric parameters were compared. Lastly, all plans were subjected to PSQA assessment by determining the gamma passing rate (GPR). RESULTS: All dosimetry results obtained from the planning target volume passed the ICRU 83 criteria. With regard to similar homogeneity indices, VMAT produced better conformity number values than HT (0.78 vs. 0.64), but differences in the values were insignificant. Furthermore, VMAT was associated with a significantly shorter mean treatment time (1.91 minutes vs. 6.66 minutes). For PSQA assessment, both techniques resulted in adequate GPR values (> 90% at the 3%/3 mm criteria). CONCLUSION: Both HT and VMAT techniques led to the generation of clinically satisfactory and reliable radiotherapy plans. However, the VMAT plan was associated with a non-significantly better degree of conformity and a significantly shorter treatment time. Thus, VMAT was determined to be a better choice for LA-NSCLC.

Conventional versus hypofractionated postmastectomy radiotherapy: a report on long-term outcomes and late toxicity.

OBJECTIVE: We evaluated the long-term outcomes and late toxicity of conventional fractionated (CF) and hypofractionated (HF) postmastectomy radiotherapy (PMRT) in terms of locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), overall survival (OS), and late toxicity. METHODS: A cohort of 1640 of breast cancer patients receiving PMRT between January 2004 and December 2014 were enrolled. Nine hundred eighty patients were treated with HF-PMRT: 2.65 Gy/fraction to a total of 42.4-53 Gy and 660 patients were treated with CF-PMRT: 2 Gy/fraction to a total of 50-60 Gy. RESULTS: The median follow-up time was 71.8 months (range 41.5-115.9 months). No significant difference was found in the rates of 5-year LRRFS, DFS, and OS of HF-PMRT vs CF-PMRT; 96% vs. 94% (p = 0.373), 70% vs. 72% (p = 0.849), and 73% vs. 74% (p = 0.463), respectively. We identified a cohort of 937 eligible breast cancer patients who could receive late toxicities assessment. With a median follow-up time of this patient cohort of 106.3 months (range 76-134 months), there was a significant higher incidence of grade 2 or more late skin (4% vs 1%) and subcutaneous (7% vs 2%) toxicity in patients treated with HF-PMRT vs CF-PMRT. Patients who received additional radiation boost were significantly higher in the HF-PMRT group. Grade 2 or more late RTOG/EORTC lung toxicity was significant lesser in HF-PMRT vs CF-PMRT (9% vs 16%). Grade 1 brachial plexopathy was also significant lesser in HF-PMRT vs CF-PMRT (2% vs 8%). Heart toxicity and lymphedema were similar in both groups. CONCLUSIONS: HF-PMRT is feasible to deliver with comparable long-term efficacy to CF-PMRT. HF-PMRT had higher grade 2 or more skin and subcutaneous toxicity but less lung and brachial plexus toxicity.

Clinical outcomes and dosimetric study of hypofractionated Helical TomoTherapy in breast cancer patients.

We present a single center's experience of treatment outcomes and dosimetric parameters for breast cancer patients treated with hypofractionated Helical TomoTherapy (HT). This is a retrospective study of one hundred and thirty-six patients with invasive breast cancer treated between March 2012 and October 2016. Dosimetric parameters and 3-year loco-regional failure free survival (LRFFS) were analyzed. Dose to ipsilateral lung, heart and contralateral breast as well as acute and late toxicities were recorded. The median follow-up time is 45 months (range: 5-83). Two patients had loco-regional failure. The 3-year LRFFS was 99%. Acute grade 1 and 2 skin toxicities occurred in 95% and 1%, respectively. Coverage of the target volumes was achieved with the mean ± standard deviation (SD) of homogeneity and conformity index being 0.1 ± 0.04, and 0.8 ± 0.07, respectively. Dose to ipsilateral lung, contralateral breast, and heart was also within the limited constraints regardless of the complexity of target volumes. Only two percent of patients experienced late grade 2 skin toxicity. No late grade 2 subcutaneous tissue toxicity was found. Nine percent of patients developed late grade 1 lung toxicity. Hypofractionated radiotherapy using Helical TomoTherapy in breast irradiation provides excellent 3-year LRFFS and minimal acute and late toxicities. A careful, longer follow-up of healthy tissue effects to lung, heart, and contralateral breast is warranted.

Short Telomere Length as a Biomarker Risk of Lung Cancer Development Induced by High Radon Levels: A Pilot Study.

Long-term exposure to radon has been determined to be the second leading cause of lung cancer after tobacco smoking. However, an in-depth study of this topic has not been explicitly carried out in Chiang Mai (Thailand). This paper presents the results of an indoor radon level measurement campaign in dwellings of Chiang Mai using total of 110 detectors (CR-39) during one year. The results show that the average radon levels varied from 35 to 219 Bq/m³, with an overall average of 57 Bq/m³. The finding also shows that the average value is higher than the global average value of 39 Bq/m³. In addition, to examine the cause of lung cancer development among people with risk of chronic exposure to radon during their lifetime, 35 non-smoker lung cancer patients and 33 healthy nonsmokers were analyzed for telomere length. As expected, telomere length was significantly shorter in lung cancer patients than in healthy nonsmokers. Among healthy nonsmokers, the telomere length was significantly shorter in a high radon group than in an unaffected low radon group. To the best of our knowledge, our research provides the first attempt in describing the shortened telomeres in areas with high levels of environmental radon that might be related to lung cancer development.

Intermediate-term results of trans-abdominal ultrasound (TAUS)-guided brachytherapy in cervical cancer.

OBJECTIVES: To report the intermediate-term results of trans-abdominal ultrasound (TAUS)-guided brachytherapy in cervical cancer. MATERIALS AND METHODS: Ninety-two patients with cervical cancer (stage IB-IVA, according to FIGO staging), were treated by curative radiotherapy from February 2012 to June 2015. All patients were treated with whole pelvic radiotherapy to 50 Gy in 25 fractions and central shielding after 44 Gy, in combination with TAUS-guided brachytherapy, in order to escalate the total dose (EQD2) to the minimal dose at cervical points (in EQD2 concepts) defined by TAUS, while maintaining low doses to ICRU bladder and rectal points. The treatment results and toxicity profiles were reported. RESULTS: At median follow-up time of 41.2 months (range 8 to 61 months) the pelvic control, disease-free survival, and overall survival rates were 84.8%, 75%, and 88%, respectively. The mean applied doses to cervix, bladder, and rectal points were 83.5, 72.3, and 76.5 Gy, respectively. Eight patients developed grade 2 Gastrointestinal toxicity. CONCLUSION: The 3-year results demonstrated that TAUS-guided brachytherapy is feasible and associated with excellent tumor control/toxicity rates in cervical cancer.

The Outcome of the First 100 Nasopharyngeal Cancer Patients in Thailand Treated by Helical Tomotherapy.

BACKGROUND: The aim of the study was to analyse of two-year loco-regional failure free survival (LRFFS), distant metastasis free survival (DMFS), overall survival (OS), and toxicity outcomes of the first 100 nasopharyngeal carcinoma patients in Thailand treated by helical tomotherapy. PATIENTS AND METHODS: Between March 2012 and December 2015, 100 patients with non-metastatic nasopharyngeal carcinoma were treated by helical tomotherapy. All patients were treated by platinum-based concurrent chemoradiotherapy and adjuvant or neo-adjuvant chemotherapy. RESULTS: The median age was 51 years (interquartile ranges [IQR]: 42.5-57.0). The mean ± SD of D95% of planning target volume (PTV) 70, 59.4 and 54 were 70.2 ± 0.5, 59.8 ± 0.6, and 54.3 ± 0.8 Gy, respectively. The mean ± SD of conformity index, and homogeneity index were 0.89 ± 0.13 and 0.06 ± 0.07. Mean ± SD of D2 % of spinal cord and brainstem were 34.1 ± 4.4 and 53.3 ±6.3 Gy. Mean ± SD of D50 of contralateral and ipsilateral parotid gland were 28.4 ± 6.7 and 38.5 ± 11.2 Gy. At a median follow-up of 33 months (IQR: 25-41), the 2-year LRFFS, DMFS, OS were 94% (95%CI: 87-98%), 96% (95% CI: 89-98%), and 99% (95% CI: 93-100%), respectively. Acute grade 3 dermatitis, pharyngoesophagitis, and mucositis occurred in 5%, 51%, and 37%, respectively. Late pharyngoesophagitis grade 0 and 1 were found in 98% and 2% of patients. Late xerostomia grade 0, 1 and 2 were found in 17%, 78% and 5%, respectively. CONCLUSIONS: Helical tomotherapy offers good dosimetric performance and achieves excellent treatment outcome in nasopharyngeal carcinoma patients.

Combined chemoradiation of cisplatin versus carboplatin in cervical carcinoma: a single institution experience from Thailand.

BACKGROUND: To report the results of combined chemoradiation (CCRT) with cisplatin versus carboplatin in locally advanced cervical carcinoma. METHODS: From 2009 to 2013, 255 patients with stage IIB-IVA cervical carcinoma, according to FIGO staging were prospectively assigned to be treated with pelvic radiotherapy followed by brachytherapy given concurrently with cisplatin or carboplatin in the treatment of locally advanced cervical cancer. Treatment outcomes and toxicitiy were evaluated. RESULTS: Two-hundred and thirteen patients could be evaluated. At a median follow-up time of 43 months (6-69 months), the 3-year local control, disease-free survival, metastasis-free survival and overall survival rates were 93, 80.8, 85.0 and 87.3 %, respectively. No statistical difference in terms of local control, disease-free survival, metastasis-free survival and overall survival rates between cisplatin and carboplatin treatments was observed in this study. Eighty-six percents of the patients in the carboplatin group could receive more than 4 cycles, while there were only 72 % in the cisplatin group who completed more than 4 cycles (p = 0. 02). In terms of acute toxicity, cisplatin caused significantly more anemia (p = 0.026), neutropenia (p = 0. 044) and nephrotoxicity (p = 0. 031) than carboplatin. No difference in late toxicity was observed in this study. CONCLUSION: Carboplatin yielded comparable results to cisplatin in concurrent chemo-radiation for locally advanced cervical cancer. In addition, carboplatin was associated with a better compliance rate and was associated with less of anemia, neutropenia and nephrotoxicity.

The using of megavoltage computed tomography in image-guided brachytherapy for cervical cancer: a case report.

We present a case of cervical cancer treated by concurrent chemoradiation. In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed. We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.