Treatment of upper gum carcinoma with high-dose-rate customized-mold brachytherapy

PURPOSE: To design an applicator for the treatment of tumors of the upper gum (UGCs) with high-dose-rate (HDR) brachytherapy. METHODS AND MATERIALS: A customized mold with four 6-Fr catheters was built. The two halves of the paired catheters form a functional loop without sharp curves. RESULTS: An adequate dose to the surface of the tumor is ensured. CONCLUSIONS: Mold-based HDR brachytherapy seems ideally suited for UGCs.     

New ambulatory implant technique of high-dose-rate interstitial brachytherapy for prostate cancer

Purpose The aim of this study was to improve the performance status of prostate cancer patients during high-dose-rate interstitial brachytherapy (HDR-ISBT). To this end, we have developed a new ambulatory implant technique. Materials and methods Ten prostate cancer patients were treated with HDR-ISBT as monotherapy from October 2003 until March 2004. We utilized a new removable template, a flexible applicator with a nonmetallic bead and button stopper, and an inner catheter connecting the applicator and the transfer tube of the brachytherapy unit. We shortened the connector end of the flexible applicator to enable the patient to sit down and walk freely during the treatment time. Results All 10 patients could walk without any support. No problem in the application was observed. Conclusion Our new ambulatory implant technique for HDR-ISBT was able to improve the performance status of prostate cancer patients.     

High-dose-rate brachytherapy for localized penile cancer: Evolution of a technique

PurposeHigh-dose-rate (HDR) brachytherapy is a convenient treatment option for selected patients with T1-T2 penile squamous cell carcinoma (SCC), providing high rates of penile preservation and tumor control. We present the results of penile SCC treated with HDR brachytherapy either interstitially or via a surface mold.Methods and MaterialsBetween November 2009 and April 2019, seven patients (2 T1a and 5 T2) were treated with interstitial HDR and 8 (1 Tis, six T1a, and one T1b) with surface mold. Prescribed dose for interstitial patients ranged from 38.4 Gy in 6 days (3.2 Gy × 12) to 53 Gy in 9 days (3.12 × 17), BID. All patients treated with mold brachytherapy received 40 Gy in 10 fractions BID. Toxicity and oncological results were assessed for both groups, and their relation with dosimetry is described.ResultsMedian follow up was 90 months for interstitial and 27 months for those treated with surface mold. Fourteen of 15 patients are alive and disease-free; one surface mold patient died of non-small-cell lung cancer. There was one relapse in each group, each treated with salvage penectomy. The potency was preserved in 82%. For interstitial, G2 necrosis occurred in 43%, G2 meatal stenosis in 29% and G3 stenosis in 14%.ConclusionsBoth techniques have excellent rates of tumor control and organ preservation. Implant geometry and homogeneity constraints must be carefully designed to minimize toxicity in interstitial brachytherapy. Urethral contouring and reporting of dosimetric parameters should be defined.     

老年头颈癌患者125I粒子植入治疗后的生存质量研究

目的 评价老年头颈癌患者碘-125(¹²⁵I)粒子植入治疗后生存质量状况。方法 选择2005年至2011年就诊于本院因头颈癌行¹²⁵I粒子植入治疗的老年患者40例,采用QOL-RTI问卷对生存质量进行调查。评价其生存质量情况,并分析治疗后影响生存质量的因素。结果 40例入选患者,治疗后维持了良好的生存质量。老年舌根癌患者粒子植入后生存质量低于其他部位癌患者;老年患者功能状况和整体生存质量随年龄增加而降低;术后辅助¹²⁵I粒子植入治疗患者生存质量(QOL)高于未能完全切除或难以手术的患者;病理类型、粒子植入数量以及治疗后时长对患者生存质量无明显影响。结论 老年头颈癌患者行¹²⁵I粒子植入术后,维持有良好的生存质量。肿瘤靶区和临床分期是影响患者生存质量的重要因素。     

A comparative analysis of overall survival between high-dose-rate and low-dose-rate brachytherapy boosts for unfavorable-risk prostate cancer

Purpose

External beam radiation therapy (EBRT) with low-dose-rate (LDR) brachytherapy boost has been associated with improved biochemical progression–free survival and overall survival (OS) compared with dose-escalated EBRT (DE-EBRT) alone for unfavorable-risk prostate cancer. However, it is not known whether high-dose-rate (HDR) boost provides a similar benefit. We compare HDR boost against LDR boost and DE-EBRT with respect to OS.

Re-irradiation with interstitial pulsed-dose-rate brachytherapy for unresectable recurrent head and neck carcinoma

PurposeTo assess the long-term results of protocol-based interstitial pulsed-dose-rate (PDR) brachytherapy combined with simultaneous chemotherapy in selected patients with recurrent head and neck tumors not amenable to salvage surgery.Methods and MaterialsA total of 51 patients with recurrent head and neck cancer were treated with interstitial PDR brachytherapy. Forty patients (78%) had salvage brachytherapy alone using a median total dose of 60 Gy. Salvage brachytherapy in combination with external beam therapy was performed in 11 patients (22%) using a median total dose of D_REF = 27 Gy. Simultaneously with the PDR brachytherapy, a concomitant chemotherapy was administered in 35/51 (69%) of patients. The analysis was performed after a median followup of 58 months.ResultsLocal control rates calculated according to Kaplan–Meier after 2 and 5 years were 71% and 57%, respectively. Comparing results of salvage PDR brachytherapy with or without simultaneous chemotherapy, the 5-year local recurrence-free survival rates were 78.9% vs. 38.5% (p = 0.01), respectively. No other patient or treatment-related parameters had a significant influence on treatment results. A total of 9/51 (17.7%) and 6/51 (11.8%) patients developed soft-tissue necrosis or bone necrosis, respectively, but only 2% of patients required surgical treatment.ConclusionsPDR interstitial brachytherapy with pulse doses between 0.4 and 0.7 Gy/h/24 h with simultaneous chemotherapy is an effective and safe option for curative therapy in selected patients with head and neck cancer in previously irradiated areas, which are not suitable for salvage surgery.     

头颈部肿瘤放疗后吞咽困难防治的研究现状

吞咽困难是头颈部肿瘤放疗后常见的不良反应,在接受放化疗的头颈部肿瘤患者中,超过76%的患者会出现吞咽困难,轻者降低生活质量,重者可能危及生命。吞咽困难的形成与肿瘤分期、治疗方法和康复计划等相关,其预防和治疗是保障头颈部肿瘤患者生活质量的关键,但是目前临床防治措施明显不完善。笔者从吞咽系统的解剖及生理过程、放疗后头颈部肿瘤患者吞咽困难的形成原因、放疗对头颈部肿瘤患者吞咽困难发生发展过程的影响、吞咽困难的评估以及吞咽功能训练等方面进行综述,以期进一步为头颈部肿瘤患者放疗后出现吞咽困难的防治提供思路。     

Interobserver variability in rectum contouring in high-dose-rate brachytherapy for prostate cancer: A multi-institutional prospective analysis

PurposeThe aim of this study was to evaluate the interobserver variability (IOV) of rectum contouring, and its dosimetric consequences, for high-dose-rate brachytherapy in patients with prostate cancer across multiple institutions.Methods and MaterialsFive radiation oncologists contoured rectums in 10 patients on transperineal ultrasound image sets after establishing a delineation consensus. The D_0.1cc, D_1cc, and D_2cc rectum volume parameters were determined. The mean, standard deviation, and range of each dose–volume histogram parameter were evaluated for each patient. The IOV was determined using the coefficient of variation, and the dosimetric impacts on the total dose were analyzed by estimating the biologically equivalent dose (EQD_{2α/β = 3}).ResultsThe interobserver coefficients of variation (±standard deviation) for the reported D_0.1cc, D_1cc, and D_2cc were 5 ± 1.84%, 4 ± 1.26%, and 4 ± 1.33%, respectively. As for the impact on the total dose, the mean dose differences for D_0.1cc, D_1cc, and D_2cc were 10 Gy, 7.3 Gy, and 6.6 Gy, respectively.ConclusionsThe D_2cc is robust as evident by the low IOV (<5%). However, some variability ranges almost overlap with the clinical threshold level, which may present dosimetric and clinical complications. General rectal contouring guidelines for prostate high-dose-rate brachytherapy are desirable to reduce discrepancies in delineation.     

头颈部肿瘤放疗相关口腔并发症和治疗

放疗是头颈部肿瘤患者常见的治疗方式。头颈部放疗常会导致口腔颌面部并发症, 因该部位组织结构复杂, 发病机制多样, 现有的治疗方案和研究进展较为局限。本文重点对最常见的放射性口腔黏膜炎、放射性唾液腺损伤及放射性龋齿进行系统总结, 回顾了现有发病机制假说、治疗及研究进展, 以期为深入研究相关病理机制和新的预防、治疗手段提供一定的参考。     

Improved survival for patients with prostate cancer receiving high-dose-rate brachytherapy boost to EBRT compared with EBRT alone

PurposeHigh-dose-rate (HDR) brachytherapy boost is a treatment of intermediate- to high-risk prostate cancer, but long-term clinical outcome data are sparse. We report long-term survival and toxicity data in a cohort of patients treated in a single institution.MethodsBetween 1998 and 2004, 654 patients with localized prostate cancer received either 3-dimensional conformal radiotherapy (median 46 Gy) with an HDR (median 18 Gy in three fractions) boost (“3-D conformal radiotherapy [3DCRT] + HDR”; 215 patients) or 3DCRT alone (“3DCRT”; median 70 Gy; 439 patients) with curative intent. Men with National Comprehensive Cancer Network intermediate risk were offered neoadjuvant androgen deprivation and with high risk were also offered adjuvant androgen deprivation. Data collection included patient-reported outcome measures.ResultsThe 3DCRT + HDR group was older (72.3 vs. 68.9 yrs), had higher presenting PSAs (iPSA) (15.66 and 12.57 ng/mL, respectively), higher proportion of Gleason scores >7 (15.3% vs. 12.4%), and higher proportions of extracapsular disease (29.3% vs. 25.5%). 3DCRT + HDR men had lower proportions of low-risk patients (3.3% vs. 19.4%) and higher proportions of high-risk patients (50.7% vs. 37.4%) than the 3DCRT group. The 5-, 10-, and 15-year overall survival was superior at 92%, 81%, and 67%, respectively, for the 3DCRT + HDR group, compared with 88%, 71%, and 53%, respectively, in the 3DCRT group (p < 0.001). The 5-, 10-, and 15-year cause specific survival also favored the HDR boost group with survival of 96%, 93%, and 87% (3DCRT + HDR) and 95% 88% and 79% (3DCRT), respectively (p < 0.037).ConclusionsHDR brachytherapy boost in conjunction with 3DCRT offered superior overall survival and cause-specific survival in our patient population.     

Computed tomography versus magnetic resonance imaging in high-dose-rate prostate brachytherapy planning: The impact on patient-reported health-related quality of life

PurposeHigh-dose-rate (HDR) prostate brachytherapy uses volumetric imaging for treatment planning. Our institution transitioned from computed tomography (CT)-based planning to MRI-based planning with the hypothesis that improved visualization could reduce treatment-related toxicity. This study aimed to compare the patient-reported health-related quality of life (hrQOL) and physician-graded toxicity outcomes of CT-based and MRI-based HDR prostate brachytherapy.MethodsFrom 2016 to 2019, 122 patients with low- or intermediate-risk prostate cancer were treated with HDR brachytherapy as monotherapy. Patients underwent CT only or CT and MRI imaging for treatment planning and were grouped per treatment planning imaging modality. Patient-reported hrQOL in the genitourinary (GU), gastrointestinal (GI), and sexual domains was assessed using International Prostate Symptom Score and Expanded Prostate Cancer Index Composite Short Form-26 questionnaires. Baseline characteristics, changes in hrQOL scores, and physician-graded toxicities were compared between groups.ResultsThe median follow-up was 18 months. Patient-reported GU, GI, and sexual scores worsened after treatment but returned toward baseline over time. The CT cohort had a lower baseline mean International Prostate Symptom Score (5.8 vs. 7.8, p = 0.03). The other patient-reported GU and GI scores did not differ between groups. Overall, sexual scores were similar between the CT and MRI cohorts (p = 0.08) but favored the MRI cohort at later follow-up with a smaller decrease in Expanded Prostate Cancer Index Composite Short Form-26 sexual score from baseline at 18 months (4.9 vs. 19.8, p = 0.05). Maximum physician-graded GU, GI, and sexual toxicity rates of grade ≥2 were 68%, 3%, and 53%, respectively, with no difference between the cohorts (p = 0.31).ConclusionOur study shows that CT- and MRI-based HDR brachytherapy results in similar rates of GU and GI toxicity. MRI-based planning may result in improved erectile function recovery compared with CT-based planning.     

头颈部肿瘤放射性甲状腺功能减退的研究现状

放疗是头颈部肿瘤重要的治疗手段,由于解剖结构复杂,放疗时甲状腺难免会受到照射,照射造成的放射性甲状腺功能减退（RIHT,radiation-induced hypothyroidism,放射性甲减）及其对身体机能的影响逐渐引起人们关注。本文就头颈部肿瘤RIHT的临床特点、发生机制、危险因素、预测模型、评估及治疗等进行综述。     

The impact of missed fractions in head and neck radiotherapy and how they can be minimised

Radiotherapy is an effective treatment for cancer, especially in cases of early stage disease, hence its continued routine use in Oncology. Overall treatment time is a significant factor which influences the efficacy of radiotherapy treatment. The accelerated reproduction of tumour clonogenic cells is considered to be a major contributory cause for reduced local control when treatment time is extended without dose compensation.It has been reported that even a one day gap can be damaging to treatment outcome with a reduction in local control being estimated at 1.4% per day of missed radiotherapy. With recent treatment compliance rates of 48.9% being observed in head and neck radiotherapy patients these factors provide the rationale for such a review. This paper reviews the current literature on the impact of missed fractions in radiotherapy for SCC head and neck and provide recommendations as to how missed fractions can be minimised.     

FDG-PET delayed imaging for the detection of head and neck cancer recurrence after radio-chemotherapy: comparison with MRI/CT

In advanced head and neck cancer, an organ-sparing approach comprising radiation therapy combined with intra-arterial chemotherapy has become an important technique. However, the high incidence of residual masses after therapy remains a problem. In this study, we prospectively evaluated the use of 2-[¹⁸F]fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) delayed imaging for the detection of recurrence of head and neck cancer after radio-chemotherapy, and compared the FDG-PET results with those of magnetic resonance imaging (MRI) or computed tomography (CT). Forty-three lesions from 36 patients with head and neck cancer suspected to represent recurrence after radio-chemotherapy (median interval from therapy, 4 months) were studied. PET was performed at 2 h after FDG injection, and evaluated. The results were compared to those of contrast studies with MRI or CT performed within 2 weeks of the PET study, and to histological diagnosis (in all patients suspected of having recurrence) or clinical diagnosis. The lesion-based sensitivity (visual interpretation) and negative predictive value of FDG-PET (88% and 91%, respectively) were higher than those of MRI/CT (75% and 67% respectively). The specificity, accuracy and positive predictive value of FDG-PET (78%, 81% and 70%, respectively) were significantly (P<0.05) higher than those of MRI/CT (30%, 47% and 39% respectively). Three of six patients with false positive findings had post-therapy inflammation. Receiver operating characteristic (ROC) analysis showed that retrospective evaluation with the standardised uptake ratio yielded the best results (sensitivity 87.5%, specificity 81.5%), followed by visual interpretation and then the tumour/neck muscle ratio. An FDG-PET delayed imaging protocol yielded significantly better results for the detection of recurrence of head and neck cancer after radio-chemotherapy than MRI/CT. Because of the high negative predictive value of FDG-PET (91.3%), if PET is negative, further invasive procedures may be unnecessary.     

Prostate high-dose-rate brachytherapy as salvage treatment of local failure after previous external or permanent seed irradiation for prostate cancer

PURPOSE: To report our results in using high-dose-rate (HDR) brachytherapy for salvage of local-only failure, after either external beam radiation or permanent seed implant. METHODS AND MATERIALS: The data from 7 patients treated with salvage HDR brachytherapy at our institution was retrospectively reviewed. Information was gathered from chart review and prostate HDR specific questionnaires completed at followup visits. RESULTS: All 7 patients had local-only failure defined by transrectal biopsy. Median followup is 58 months (range, 27-63), with a 71% disease-free survival rate; median survival has not yet been reached. Two patients died of metastatic disease. There have been no further local failures. There has been no Grade 3 or higher rectal injuries. Five patients (71%) developed symptomatic urethral strictures; two previous seed failures developed incontinence with urethral necrosis, salvaged by placement of artificial sphincter or continent catheter channel. These results compare favorably to reported results with salvage permanent seed brachytherapy, prostatectomy, and cryotherapy. CONCLUSIONS: HDR brachytherapy as salvage of local-only failure after previous radiation has limited data reported to date. The disease control rates and complications of treatment compare very favorably with those reported using other modalities. This approach merits further investigation.     

Dosimetric and clinical outcome in image-based high-dose-rate interstitial brachytherapy for anal cancer

PurposeTo evaluate dosimetric and clinical outcome in patients of anal cancer treated with image-based interstitial high-dose-rate brachytherapy following chemoradiation.Methods and MaterialsSixteen patients with anal cancer were treated with chemoradiation followed by brachytherapy boost with image-based high-dose-rate interstitial brachytherapy from January 2007 to June 2011. Two brachytherapy dose schedules were used: 21 Gy in seven fractions and 18 Gy in six fractions depending on response to chemoradiation. CT scan was done after placement of needles for confirmation of placement and treatment planning. Target volume was contoured on CT scans. Volumetric quality indices and dose parameters were calculated.ResultsThe mean clinical target volume was 17.7 ± 4.98 cm³, and the median overall tumor size was 4.2 cm (3.4–5 cm). The mean values of coverage index, dose homogeneity index, overdose volume index, dose non-uniformity ratio, and conformal index were 0.94, 0.83, 0.21, 0.37, and 0.88, respectively. With a median followup of 41 months (range, 20–67.2 months), preservation of the anal sphincter was achieved in 14 patients. The 1- and 2-year local control rates were 93.8% and 87.5%, respectively. Treatment was well tolerated and none of the patients developed Grade 3 or higher late toxicity.ConclusionsThe combination of external beam radiotherapy with interstitial brachytherapy increases the dose to the tumor volume and limits the volume of irradiated normal tissue, thereby decreasing late toxicity. The use of image-based treatment planning provides better dose conformality with reduced toxicity and helps to prevent a geographic miss.     

头颈部肿瘤放疗中转化医学相关机制的研究进展

头颈部肿瘤是目前世界上最常见的肿瘤之一,超过90%的头颈部肿瘤为鳞状细胞癌。放疗在头颈部肿瘤的治疗中显得尤为重要,目前国内治疗早期肿瘤可以单纯放疗为主,晚期肿瘤则选择综合性治疗。转化医学是近些年来新的研究重点,将科研过程及其成果与临床紧密结合,尤其体现在通过检测患者肿瘤组织中的基因突变靶点及基因单核苷酸多态性分型、mRNA基因定量表达,为临床提供靶向及个体化放疗的依据,能显著提高治疗的有效率。