The aim of the study was to compare incidences of late gastrointestinal adverse events and clinical outcomes between 3D conformal radiation therapy (3DCRT) and intensity-modulated radiation therapy (IMRT) after radical hysterectomy for cervical cancer patients. Between March 2007 and May 2014, 73 cervical cancer patients with high-risk prognostic factors (pelvic lymph node metastasis and/or parametrial invasion) underwent postoperative pelvic radiation therapy (RT) after radical hysterectomy. Of these patients, 33 (45%) and 40 (55%) received 3DCRT and IMRT, respectively. Because the gastrointestinal obstruction rate after postoperative pelvic 3DCRT was high, no concurrent chemotherapy was applied until 2015. The median follow-up period for patients with 3DCRT and IMRT was 82 months (6–113) and 50 months (5–74), respectively. There was no significant difference in overall survival (OS) (4-year OS: 85% vs 78%, P = 0.744) or disease-free survival (DFS) (4-year DFS: 73% vs 64%, P = 0.696) between the two groups. Eleven (33%) and 13 (33%) patients experienced recurrence after 3DCRT and IMRT, respectively. The patients who had vaginal invasion from the postoperative pathological finding more frequently had loco-regional recurrence than the patients who did not have vaginal invasion (2.3% vs 17%, P = 0.033). Gastrointestinal obstruction was observed in 9 (27%) and 3 (7.5%) patients for 3DCRT and for IMRT, respectively (P = 0.026). Severe gastrointestinal obstruction that required surgery was observed in 6 (19%) patients, all of whom received adjuvant RT by 3DCRT. IMRT could reduce the incidence of late severe gastrointestinal obstruction after postoperative pelvic RT with a non-inferior clinical efficacy compared with 3DCRT.

Perirectal hyaluronate gel injection (HGI) appears to be a promising technique for healthy tissue dose sparing in pelvic radiotherapy. In this analysis, we report our initial experience of HGI in gynecologic brachytherapy, focusing on its safety and effectiveness for dose reduction to the rectum. Between July 2013 and May 2014, 36 patients received HGI for primary/salvage gynecologic brachytherapy. Dosimetric effect analysis was based on pre- and post-HGI computed tomography dataset registration with corresponding dose–volume histogram evaluation. The maximum dose to the most exposed 0.1 cm³ (D_0.1cm³) and 2.0 cm³ (D_2.0cm³) were used as index values for rectum and bladder dose evaluation. The dose indexes for target volume (TV) coverage were TV D90/V100. In all cases, HGI was well tolerated, with no acute or late adverse events documented at a median follow-up of 220 days (range, 18–1046 days). Rectum D_2.0cm³ and D_0.1cm³ were significantly decreased by HGI (P < 0.001 and P = 0.003, respectively), with no significant impact on dosimetric parameters of bladder and TV coverage. Factors correlating negatively with the dosimetric effect of HGI were an increasing number of interstitial catheters (P = 0.003) as well as Lcranial100% (P = 0.014) and Lcranial80% (P = 0.001) [i.e. the length from the anal verge to the most cranial point at which the 100% and 80% isodose lines, respectively, crossed the rectum]. The concept of HGI for gynecologic brachytherapy is plausible, and our initial experience indicates it to be an effective technique for rectal dose reduction in radiotherapy of intrapelvic tumours.

Locally advanced uterine cervical cancer (LAUCC) with lateral tumor extension may not always be covered adequately by conventional intracavitary brachytherapy (ICBT). Hybrid intracavitary and interstitial brachytherapy (HBT) seems to be an effective alternative by improving anatomy-oriented dose optimisation. The purpose of this study was to report initial clinical result for LAUCC treated by HBT. Between January 2012 and November 2015, 42 patients with LAUCC (T1b2-4a) were treated with primary radiation therapy including HBT. Patients with distant metastasis other than para-aortic lymph node spread were excluded from this study. A retrospective analysis was performed for toxicity evaluation and oncological outcome calculation. Median follow-up was 23.2 months (range 13.2–71.4). Two-year overall survival, progression free survival, and local control rate were 81.6, 54.4, and 80.2%, respectively. Seven patients experienced local recurrence (16.6%). Of those, five were confined to the uterus and two at the parametria. Late adverse events ≥ grade 3 were seen in 3 patients. HBT can generate favorable local control in tumors which cannot be adequately covered by ICBT.

Definitive radiotherapy for patients with scalp angiosarcoma has a poor prognosis, often resulting in severe skin adverse events. Additionally, malignant melanoma is known for its radioresistant nature. Boron neutron capture therapy (BNCT) may address these challenges due to the high uptake capacity of boron drugs in these cancer types. We aimed to determine the treatment dose for BNCT and evaluate the incidence of acute adverse events AEs following BNCT in patients with primary or recurrent angiosarcoma/malignant melanoma of the skin. This was a single-center, non-randomized clinical trial with a three-step dose escalation plan, involving maximum skin doses of 12, 15, and 18 Gy-Eq following a 3 + 3 design. The patients underwent BNCT between November 2019 and April 2022. The primary endpoint was to evaluate the incidence of acute adverse events. Ten patients (scalp angiosarcomanine, forefinger malignant melanoma: one) were included. The median target lesion size was 46.5 (range: 20-145) mm. A transient asymptomatic increase in serum amylase level was the only grade 3 adverse event. The best overall response rate within 180 days was 70 % (median tumor shrinkage rate: 77.5 % [4.9-100 %]). BNCT with a dose of 18 Gy-Eq is a feasible treatment option, demonstrating a favorable safety profile and a high response rate in patients with primary or recurrent angiosarcoma or malignant melanoma of the skin.

Background: In definitive radiation therapy for prostate cancer, the SpaceOAR® System, a hydrogel spacer, is widely used to decrease the irradiated dose and toxicity of rectum. On the other hand, periprostatic abscesses formation and rectal perforation are known as rare adverse effects of SpaceOAR. Nevertheless, there is a lack of reports clarifying the association between aggravation of abscesses and radiation therapy, and hyperbaric oxygen therapy (HBOT) is effective for a peri-SpaceOAR abscess and rectal perforation. Case presentation: We report a case of a 78-year-old high-risk prostate cancer patient. After SpaceOAR insertion into the correct space, he started to receive external beam radiation therapy (EBRT). He developed a fever, perineal pain and frequent urination after the completion of EBRT, and the magnetic resonance imaging (MRI) revealed a peri-SpaceOAR abscess. Scheduled brachytherapy was postponed, administration of antibiotics and opioid via intravenous drip was commenced, and transperineal drainage was performed. After the alleviation of the abscess, additional EBRT instead of brachytherapy was performed with MRI-guided radiation therapy (MRgRT). On the last day of the MRgRT, perineal pain reoccurred, and MRI and colonoscopy detected the rectal perforation. He received an intravenous antibiotics drip and HBOT, and fully recovered from the rectal perforation. Conclusions: Our report indicates that EBRT can lead to a severe rectum complication by causing inflammation for patients with a peri-SpaceOAR abscess. Furthermore, HBOT was effective for the peri-SpaceOAR abscess and rectal perforation associated with EBRT.