DNA damage response in a 2D-culture model by diffusing alpha-emitters radiation therapy (Alpha-DaRT).

Diffusing alpha-emitters radiation therapy (Alpha-DaRT) is a unique method, in which interstitial sources carrying 224Ra release a chain of short-lived daughter atoms from their surface. Although DNA damage response (DDR) is crucial to inducing cell death after irradiation, how the DDR occurs during Alpha-DaRT treatment has not yet been explored. In this study, we temporo-spatially characterized DDR such as kinetics of DNA double-strand breaks (DSBs) and cell cycle, in two-dimensional (2D) culture conditions qualitatively mimicking Alpha-DaRT treatments, by employing HeLa cells expressing the Fucci cell cycle-visualizing system. The distribution of the alpha-particle pits detected by a plastic nuclear track detector, CR-39, strongly correlated with γH2AX staining, a marker of DSBs, around the 224Ra source, but the area of G2 arrested cells was more widely spread 24 h from the start of the exposure. Thereafter, close time-lapse observation revealed varying cell cycle kinetics, depending on the distance from the source. A medium containing daughter nuclides prepared from 224Ra sources allowed us to estimate the radiation dose after 24 h of exposure, and determine surviving fractions. The present experimental model revealed for the first time temporo-spatial information of DDR occurring around the source in its early stages.

A Case of Radiation-Induced Brachial Plexopathy Below the Tolerance Dose.

This case report details a rare instance of radiation-induced brachial plexopathy (RIBP) occurring below the typical tolerance dose in a 55-year-old woman following chemoradiotherapy for apical non-small cell lung carcinoma. Despite receiving a radiation dose considered safe (47-48 Gray in 25 fractions), she developed sensory abnormalities and motor weakness in the right upper limb. The diagnostic distinction between RIBP and tumor recurrence was achieved using MRI, which showed characteristic features of radiation-induced damage. The patient's medical history included smoking and rheumatoid arthritis, highlighting the role of patient-specific factors in the development of RIBP. The case underscores the importance of recognizing RIBP as a potential diagnosis in patients with new-onset brachial plexopathy post-radiation therapy, even when radiation exposure is within conventional safety limits. This report contributes to the literature by demonstrating that RIBP can occur at lower-than-expected radiation doses, especially in the presence of contributing factors like neurotoxic chemotherapy and individual patient risks. It emphasizes the need for careful assessment and management in such cases to distinguish between RIBP and cancer recurrence.

Feasibility of accelerated partial breast irradiation with strut-adjusted volume implant brachytherapy in Japan focusing on dosimetry and acute toxicity: a Japanese multi-institutional prospective study.

BACKGROUND: A Japanese multi-institutional prospective study was initiated to investigate the effectiveness and safety of accelerated partial breast irradiation (APBI) using strut-adjusted volume implant (SAVI) brachytherapy, with subjects registered between 2016 and 2021. Herein, we report the preliminary results on the feasibility of this treatment modality in Japan, focusing on the registration process, dosimetry, and acute toxicities. PATIENTS AND METHODS: Primary registration was conducted before breast-conserving surgery (BCS) and the eligibility criteria included the following: age ≥ 40 years, tumor unifocal and unicentric, ≤ 3 cm in diameter, cN0M0, proven ductal, mucinous, tubular, medullary, or lobular carcinoma by needle biopsy. Secondary registration was conducted after BCS had been performed leaving a cavity for device implantation and pathological evaluations, and the eligibility criteria were as follows: negative surgical margin, tumor ≤ 3 cm in diameter on gross pathological examination, histologically confirmed ductal, mucinous, tubular medullary, colloid, or lobular carcinoma, pN0, L0V0, no extensive ductal component, no initiation of chemotherapy within 2 weeks of the brachytherapy APBI planning with SAVI was performed for the patients successfully entered in the study by the secondary registration process, and the treatment was administered at the dose of 34 Gy in 10 fractions administered twice daily. RESULTS: Between 2016 and 2021, 64 women were enrolled in the study through primary registration, of which 19 were excluded from the secondary registration process, and in one, it was deemed impossible to comply with the dose constraints established during treatment planning. After the exclusion of these latter 20 patients, we treated the remaining 44 patients by APBI with SAVI. The dose constraints could be adhered to in all the patients, but re-planning was necessitated in 3 patients because of applicator movement during the treatment period. Grade 2 acute toxicities were observed in 18% of all patients, but more severe acute toxicities than Grade 2 were not observed in any of the patients. CONCLUSION: APBI with SAVI brachytherapy is feasible in Japan from the aspects of compliance with dose constraints and frequency of acute toxicities.

Time to Pain Relapse After Palliative Radiotherapy for Bone Metastasis: A Prospective Multi-institutional Study.

BACKGROUND/AIM: Low risk asymptomatic bone metastasis (LRABM) without gross osteolytic changes tends to be out of indication for radiotherapy. The aim of this study was to evaluate the time between the end of palliative radiotherapy of bone metastasis (BM) until the start of new pain, in patients with painful BM. PATIENTS AND METHODS: Patients with BM were prospectively assessed for location and strength of pain every month for one year after radiotherapy. The correlation of pain relapse at irradiated site, and pain onset outside the irradiated site was evaluated with sex, age, primary tumor, pathology of tumor, visceral metastases, baseline scores for Eastern Cooperative Oncology Group performance status (PS), and baseline verbal rating scale (VRS). RESULTS: A hundred and thirty-two patients were included (79 males and 53 females). Median age was 66 years. Primary sites were lung (n=60), breast (n=17), colon (n=12), prostate (n=11), and others (n=33) (one patient had two primary sites). Median follow-up was 185 days. Pain relief was observed in 92 patients (86.0%). Out of them, pain progression was observed in 69.6%. Median time to pain progression was 75.5 days. Pain onset outside the irradiated site was observed in 57 patients (43.2%). Median time to pain onset was 109 days. Out of the 57 patients, 13 (22.8%) had LRABM which existed before the start of radiotherapy. There were 54 patients with LRABM in this study and because many patients had more than one LRABM, the total LRABM sites were 123. Out of them, pain onset was observed within one year after irradiation in 44 (36%) lesions. Median time to pain onset was 67 days, which was the shortest of the three: irradiated site, out of the irradiated site, and LRABM site. Risk factors for high probability of pain onset within one year in LRABM lesions were female sex (showing a trend in univariate analysis), and pelvic, skull and spine metastasis (significant in multivariate analysis). CONCLUSION: Time to pain onsets in LRABM are relatively short, especially in female patients with pelvic, skull and spine metastasis. In these patients, prophylactic radiotherapy could be an option to consider.

Retrograde Migration of an Au-198 Grain to the Submandibular Gland Post Brachytherapy Treatment of Floor of Mouth Cancer.

At our institution, radiation oncologists routinely treat early-stage oral cancer with low-dose-rate brachytherapy (LDR-BRT) using Au-198 grains. In this report, we show a unique case of a patient with a gold grain located within the submandibular gland, found incidentally during follow-up after LDR-BRT for floor of mouth cancer. One month after the implant, he showed sialadenitis-like symptoms, but the pain resolved two months later. All the grains were detected around the anterior sublingual area by computed tomography (CT) four months after the implant. Unexpectedly, 11 months after the implant, CT revealed that a grain was located in an intraglandular site of the submandibular gland. This finding clearly demonstrates that the grain entered Wharton's duct and retrogradely migrated to the submandibular gland through the duct. As a mechanism of the calculus formation within Wharton's duct, retrograde migration of foreign bodies to the inside of the duct has been proposed. Our incidental finding after LDR-BRT highlights the need for monitoring post-LDR-BRT using Au-198 grains for the treatment of floor of mouth cancer and sheds additional light on retrograde theory within Wharton's duct.

Efficacy and Safety of Induction Chemotherapy and/or External Beam Radiotherapy Followed by Brachytherapy in Patients With Tongue Cancer.

BACKGROUND/AIM: To evaluate the outcomes of induction chemotherapy and/or external beam radiotherapy (EBRT) followed by brachytherapy (BT) in patients with tongue cancer who had a waiting period for BT or a large tumor that was not suitable for BT. PATIENTS AND METHODS: As an induction therapy, chemotherapy with tegafur/gimeracil/oteracil (S-1), EBRT or both S-1 chemotherapy and EBRT was prescribed. BT was performed using Au-198 grains or Ir-192 pins. Local control (LC), lymph node metastasis-free survival (LNMFS), overall survival (OS), and complication rates were calculated. RESULTS: Forty-nine patients were enrolled in this study. The 3-year LC, LNMFS, and OS rates for cT1-2 patients were 84%, 45%, and 69%, respectively. The 3-year LC, LNMFS, and OS rates for cT3 patients were 77%, 58%, and 79%, respectively. The incidence of Grade 3 or 4 complications was 6%. CONCLUSION: Induction therapy contributed to the efficacy of the subsequent BT in LC rate.

Outcomes of radiotherapy in advanced external auditory canal cancer.

External auditory canal cancer (EACC) is a rare malignant tumor. In the present study, we retrospectively evaluated the treatment results in patients with advanced EACC who were treated using external-beam radiotherapy (EBRT) combined with chemotherapy or radical surgery. Overall, 21 patients with Stage III (n = 8) or Stage IV (n = 13) EACC who underwent initial treatment at our hospital between 2003 and 2016 were enrolled in this study. The 2-year overall survival (OS) and locoregional control (LRC) rates of all patients were 62% and 71%, respectively. The 2-year OS and LRC rates in patients who had received EBRT and concurrent chemotherapy with docetaxel, cisplatin and 5-fluorouracil (TPF, n = 6) were 100%. These results were higher than the 2-year OS and LRC rates of 62% and 69%, respectively, in patients who had received radical surgery and EBRT (n = 13). The rates were 0% in those who had neither received TPF nor undergone surgery in addition to EBRT (n = 2). Grade 3 bone or soft tissue necrosis was observed in 2 patients who had undergone surgery and postoperative EBRT. Our data suggest that the combination therapy of EBRT and surgery and/or chemotherapy may be the most effective treatment options for advanced EACC, and EBRT with concurrent chemotherapy with TPF is potentially the most acceptable.

Temporo-spatial cell-cycle kinetics in HeLa cells irradiated by Ir-192 high dose-rate remote afterloading system (HDR-RALS).

BACKGROUND: Intracavitary irradiation plays a pivotal role in definitive radiotherapy for cervical cancer, and the Ir-192 high dose-rate remote afterloading system (HDR-RALS) is often used for this purpose. Under this condition, tumor tissues receive remarkably different absorption doses, with a steep gradient, depending on distance from the radiation source. To obtain temporo-spatial information regarding cell-cycle kinetics in cervical cancer following irradiation by Ir-192 HDR-RALS, we examined HeLa cells expressing the fluorescence ubiquitination-based cell cycle indicator (Fucci), which allowed us to visualize cell-cycle progression. METHODS: HeLa-Fucci cells, which emit red and green fluorescence in G1 and S/G2/M phases, respectively, were grown on 35-mm dishes and irradiated by Ir-192 HDR-RALS under normoxic and hypoxic conditions. A 6 French (Fr) catheter was used as an applicator. A radiation dose of 6 Gy was prescribed at hypothetical treatment point A, located 20 mm from the radiation source. Changes in Fucci fluorescence after irradiation were visualized for cells from 5 to 20 mm from the Ir-192 source. Several indices, including first green phase duration after irradiation (FGPD), were measured by analysis of time-lapse images. RESULTS: Cells located 5 to 20 mm from the Ir-192 source became green, reflecting arrest in G2, in a similar manner up to 12 h after irradiation; at more distant positions, however, cells were gradually released from the G2 arrest and became red. This could be explained by the observation that the FGPD was longer for cells closer to the radiation source. Detailed observation revealed that FGPD was significantly longer in cells irradiated in the green phase than in the red phase at positions closer to the Ir-192 source. Unexpectedly, the FGPD was significantly longer after irradiation under hypoxia than normoxia, due in large part to the elongation of FGPD in cells irradiated in the red phase. CONCLUSION: Using HeLa-Fucci cells, we obtained the first temporo-spatial information about cell-cycle kinetics following irradiation by Ir-192 HDR-RALS. Our findings suggest that the potentially surviving hypoxic cells, especially those arising from positions around point A, exhibit different cell-cycle kinetics from normoxic cells destined to be eradicated.

Permanent interstitial re-irradiation with Au-198 seeds in patients with post-radiation locally recurrent uterine carcinoma.

This study sought to analyze the outcome of patients with post-treatment locally recurrent uterine carcinoma treated with Au-198 seed permanent interstitial re-irradiation (Au-198 IRI). A retrospective review of the data of 15 patients with post-treatment locally recurrent uterine carcinoma treated with Au-198 IRI between 1991 and 2009 was performed to evaluate the disease response, local control, overall survival and complication rates. All the patients had received definitive radiation therapy or surgery as the initial treatment. None were judged as being suitable candidates for surgical treatment, and were referred for Au-198 IRI. Au-198 IRI was performed for the vaginal wall in 8 patients, vaginal stump in 4 patients, vulva in 2 patients, and cervix in 1 patient. The median tumor volume was 1.3 cm(3)(range, 0.4-6.9), the median treated volume was 6.3 cm(3)(range, 1.8-11), and the median prescribed dose was 76 Gy (range, 68-90). At a median follow-up duration of 19 months (range, 4.3-146.9), 13 of 15 patients (87%) showed complete responses after Au-198 IRI, although 10 of these 13 patients (77%) developed repeat central recurrence again between 2.5 and 49.7 months after the Au-198 IRI (median, 12.5 months). The overall 2-year local control rate and 2-year overall survival rate in the 15 patients were 33% and 64%, respectively. Two (13%) of the 15 patients experienced late complications that were more severe than Grade III. As a result, Au-198 IRI is considered to be one of the salvage treatment modalities with tolerable complications for inoperable centrally recurrent uterine carcinoma.

Salvage radiotherapy after radical prostatectomy: outcomes and prognostic factors especially focusing on pathological findings.

External beam radiotherapy is a potential salvage or adjuvant therapy after radical prostatectomy (RP). The purpose of this study was to investigate the treatment outcome of salvage radiotherapy (RT) following RP for clinically localized prostate cancer and to identify factors that may predict the outcome of salvage RT. Between 2000 and 2006, 41 patients received salvage RT because of increasing prostate-specific antigen (PSA) levels following an RP for clinically localized prostate cancer. All the patients received conformal radiotherapy to the prostate bed. The prescribed radiation dose was 60-70 Gy in 26-35 fractions. The overall 5-year biochemical disease-free survival rate was 38%. A multivariate analysis showed that the following pathological findings of the surgical specimen were significantly associated with biochemical failure following salvage RT: a high Gleason score, a negative surgical margin, seminal vesicle invasion, lymphatic vessel invasion and negative vascular invasion. Among these factors, lymphatic vessel invasion was the strongest predictor. In conclusion, the pathological features affected the outcome of salvage RT following RP. Lymphatic vessel invasion was strongly associated with the risk of biochemical failure despite salvage RT. Meanwhile, vascular invasion was not a significant hazardous factor.

Impact of concurrent chemotherapy on definitive radiotherapy for women with FIGO IIIb cervical cancer.

The purpose of this retrospective study is to investigate the impact of concurrent chemotherapy on definitive radiotherapy for the International Federation of Gynecology and Obstetrics (FIGO) IIIb cervical cancer. Between 2000 and 2009, 131 women with FIGO IIIb cervical cancer were treated by definitive radiotherapy (i.e. whole pelvic external beam radiotherapy for 40-60 Gy in 20-30 fractions with or without center shielding and concomitant high-dose rate intracavitary brachytherapy with 192-iridium remote after loading system for 6 Gy to point A of the Manchester method). The concurrent chemotherapy regimen was cisplatin (40 mg/m(2)/week). After a median follow-up period of 44.0 months (range 4.2-114.9 months) and 62.1 months for live patients, the five-year overall survival (OS), loco-regional control (LRC) and distant metastasis-free survival (DMFS) rates were 52.4, 80.1 and 59.9%, respectively. Univariate and multivariate analyses revealed that lack of concurrent chemotherapy was the most significant factor leading to poor prognosis for OS (HR = 2.53; 95% CI 1.44-4.47; P = 0.001) and DMFS (HR = 2.53; 95% CI 1.39-4.61; P = 0.002), but not for LRC (HR = 1.57; 95% CI 0.64-3.88; P = 0.322). The cumulative incidence rates of late rectal complications after definitive radiotherapy were not significantly different with or without concurrent chemotherapy (any grade at five years 23.9 vs 21.7%; P = 0.669). In conclusion, concurrent chemotherapy is valuable in definitive radiotherapy for Japanese women with FIGO IIIb cervical cancer.

Repeat brachytherapy for patients with residual or recurrent tumors of oral cavity.

PURPOSE: To analyze data from patients receiving repeat brachytherapy (re-BT) for the treatment of residual or recurrent tumor in the oral cavity. METHODS AND MATERIALS: Between January 2003 and December 2007, 62 patients who had undergone definitive BT as an initial treatment of oral cancer subsequently underwent re-BT for the treatment of residual or recurrent tumors at the diagnostic radiology and oncology department (Tokyo Medical and Dental University Hospital). Re-BT was performed 0.9-73 months (median, 5.7) after the initial BT. Au-198 grains were used as the re-BT source in all 62 patients, and an area of 0.8-6.3 cm(2) (median, 3.1) was permanently irradiated with 60-110 Gy (median, 83) according to the system of Paterson-Parker. RESULTS: The 2-year local control and overall survival rate was 53% and 66%, respectively, and local control significantly affected overall survival. Both local control and overall survival were affected by the initial tumor characteristics and the macroscopic appearance of the residual or recurrent tumor. Grade 3 or 4 complications were seen in 5 patients. The incidence of mandibular and mucosal complications was significantly related to a biologic effective dose of α/ß of 3 Gy to the surface of the gingiva and mucosa, respectively. CONCLUSION: Re-BT using Au-198 grains for the treatment of residual or recurrent tumor after definitive BT in the oral cavity is effective and well tolerated.

Outcomes in patients with early-stage hypopharyngeal cancer treated with radiotherapy.

PURPOSE: To analyze the outcome in patients with early-stage hypopharyngeal cancer (HPC) who were treated with radiotherapy (RT). METHODS AND MATERIALS: Between February 1988 and February 2007, 77 patients with Stage I or Stage II HPC underwent definitive RT in the Division of Radiation Oncology at the National Cancer Center Hospital. Eleven of the patients received local irradiation, and the other 66 patients received elective bilateral neck irradiation and booster irradiation to the primary lesion. The median follow-up period for all the patients was 33 months from the start of RT, ranging from 3 to 229 months. RESULTS: The rates of overall survival, HPC-specific survival, HPC recurrence-free survival, and local control with laryngeal voice preservation for the 77 patients at 5 years were 47%, 74%, 57%, and 70%, respectively. The survival rates were not affected by the patient characteristics or treatment factors, but the RT field was significantly correlated with local control in a multivariate analysis. Seven of the patients had Grade 3 or greater complications, but these complications occurred after salvage surgery in 6 of the patients. Of the 77 patients, 83% had synchronous or metachronous malignancies, but these malignancies did not influence the survival of the patients if the malignancies were detected at an early stage. CONCLUSION: RT is an appropriate treatment method for early-stage HPC. However, because synchronous or metachronous malignancies occur at a relatively high frequency, careful follow-up and the early detection of such malignancies are critical.

Electron therapy for orbital and periorbital lesions using customized lead eye shields.

PURPOSE: To establish the protective efficacy against late complications of electron therapy using customized lead eye shields in cases with orbital and periorbital lesions. METHODS: Between 1982 and 2006, 16 patients with 22 orbital and periorbital lesions were treated by electron therapy. Customized lead eye shields were prepared and placed in the respective patients' eyes during each fraction of electron therapy. The toxicity and local control rates were analyzed. RESULTS: The preparation period for the customized lead eye shields was 2 days. The shields could be used throughout the treatment period in all the patients. No evidence of radiation cataract was observed in 15 of the 16 patients. None of the patients developed corneal ulceration or evidence of lead poisoning. CONCLUSION: Customized lead eye shields could be made relatively quickly, and electron therapy for orbital and periorbital lesions could be undertaken safely without any late complication.

Quality of life of oral cancer patients after low-dose-rate interstitial brachytherapy.

PURPOSE: To assess the quality of life (QOL) of oral cancer patients treated with low-dose-rate interstitial brachytherapy (LDR-BT) alone. METHODS AND MATERIALS: Between June 2005 and July 2006, a total of 56 patients with oral cancer were enrolled in this prospective study. QOL was assessed by means of the core questionnaire and head and neck questionnaire module of the European Organization for Research and Treatment of Cancer (EORTC Quality of Life Questionnaire-Core 30 [QLQ-C30] and QLQ Head and Neck 35 [H&N35]). The questionnaires were distributed to the patients before the start of treatment and 3 months, 6 months, and 12 months after the start of LDR-BT. RESULTS: It was possible to analyze the results for 20 of the initial 56 patients because they did not experience metastasis or recurrence during this study. No functions or symptoms asked about in the QLQ-C30 deteriorated during the first year. The emotional function score steadily and significantly increased. No symptoms in the QLQ-H&N35 significantly deteriorated. The scores for pain, trouble with social eating, and weight loss on the QLQ-H&N35 steadily and significantly decreased. Age, gender, and LDR-BT source had no effect on the change in QOL during the first year, but T-stage significantly affected the change in global health status, tumor site affected the changes in swallowing, sensory problems, sticky saliva, and complications affected the changes in pain, swallowing, and mouth opening. CONCLUSIONS: QOL of oral cancer patients treated with LDR-BT is high. However, tumor stage, tumor site, and complications affected the changes in a few functions and symptoms during the first year.

Radiotherapy doses at special reference points correlate with the outcome of cervical cancer therapy.

PURPOSE: The authors analyzed the correlation between radiotherapy doses at reference points on the uterine edge and the rectal wall and both pelvic control and late rectal complications of cervical cancer therapy. METHODS AND MATERIALS: Between 1997 and 2005, 57 patients with Stages IB-IVA cancer of uterine cervix were treated with a combination of external beam radiotherapy and high-dose-rate intracavitary brachytherapy. Their high-dose-rate intracavitary brachytherapy was planned by dose-point optimization at six dose points located on the edge of uterus by computed tomography. A rectal reference point located on the anterior wall of the rectum by computed tomography was also used. The pelvic control rate and the rate of late rectal complications were calculated according to the biologically effective dose (BED) at each point and several clinical parameters. RESULTS: The overall 3-year pelvic control rate was 69.4%. The patients with a BED >80 Gy10 at the point on the edge of the uterine cervix had better pelvic control (78.4% at 3 years) than the patients with a BED < or =80 Gy10 (54.4% at 3 years), and the difference was significant. The difference in the BED (Gy3) at the rectal reference point between the patients with Grade 0-1 late rectal complications (median, 114 Gy) and the patients who developed Grade > or =2 late rectal complications (median, 178 Gy) was significant. Chemotherapy was a borderline significant parameter in regard to correlation with pelvic control and late rectal complications, but there were no correlations with other dosimetric or clinical parameters. CONCLUSIONS: The radiotherapy dose at the reference point on the edge of the cervix affected pelvic control more than the clinical parameters, and the dose at the rectal reference point was more strongly correlated with the occurrence of late rectal complications.

Prediction of lymphatic metastasis based on gene expression profile analysis after brachytherapy for early-stage oral tongue carcinoma.

BACKGROUND AND PURPOSE: The management of lymphatic metastasis of early-stage oral tongue carcinoma patients is crucial for its prognosis. The purpose of this study was to evaluate the predictive ability of lymphatic metastasis after brachytherapy (BRT) for early-stage tongue carcinoma based on gene expression profiling. PATIENTS AND METHODS: Pre-therapeutic biopsies from 39 patients with T1 or T2 tongue cancer were analyzed for gene expression signatures using Codelink Uniset Human 20K Bioarray. All patients were treated with low dose-rate BRT for their primary lesions and underwent strict follow-up under a wait-and-see policy for cervical lymphatic metastasis. Candidate genes were selected for predicting lymph-node status in the reference group by the permutation test. Predictive accuracy was further evaluated by the prediction strength (PS) scoring system using an independent validation group. RESULTS: We selected a set of 19 genes whose expression differed significantly between classes with or without lymphatic metastasis in the reference group. The lymph-node status in the validation group was predicted by the PS scoring system with an accuracy of 76%. CONCLUSIONS: Gene expression profiling using 19 genes in primary tumor tissues may allow prediction of lymphatic metastasis after BRT for early-stage oral tongue carcinoma.

Curative brachytherapy for recurrent/residual tongue cancer.

PURPOSE: The efficacy of curative low-dose-rate (LDR) brachytherapy for recurrent and/or residual cancer following radical operation or irradiation and posttreatment quality of life (QoL) were assessed. PATIENTS AND METHODS: Between January 1979 and April 2004, 88 patients who had received curative LDR brachytherapy (28 with postoperative close or positive margins, six with postoperative recurrence, six with recurrence after external-beam irradiation, and 48 with recurrent/residual cancer after curative brachytherapy) were analyzed retrospectively. Late complications were assessed based on the RTOG/EORTC late radiation morbidity score scheme. RESULTS: The 5-year relapse-free and cause-specific survival rates were 92% and 96%, respectively, in the close/positive margin group and 52% and 56%, respectively, in the postbrachytherapy recurrence or residual cancer group. The incidence of late side effects was 8% (2/26) in the close or positive margin group and 22% (4/18) in the postbrachytherapy group. The only grade 4 late complication (bone exposure) was observed in one patient in the postbrachytherapy group. CONCLUSION: LDR brachytherapy as reirradiation for recurrent/residual tongue cancer was effective, and there was no increase in complications.

Acute and late genitourinary toxicity of conformal radiotherapy for prostate cancer.

PURPOSE: The aim of this study was to identify predictive factors for genitourinary (GU) toxicity in prostate cancer patients who underwent conformal radiotherapy (CRT). MATERIALS AND METHODS: In this study we analyzed 154 cases of T1-3N0M0 prostate adenocarcinoma and evaluated the occurrence rate of acute and late GU toxicity and the duration of acute toxicity according to clinical parameters: age, transurethral resection of the prostate prior to CRT, hormone therapy, CRT dose, length of planning target volume (PTV). RESULTS: Altogether, 41% of the patients developed grade 2 or higher acute GU toxicity. Longer PTV was significantly associated with a higher incidence of acute GU toxicity (>7 cm, 53%;

Brachytherapy of stage II mobile tongue carcinoma. Prediction of local control and QOL.

BACKGROUND: There is no consensus as to the prognostic model for brachytherapy of tongue carcinoma. This study was designed to evaluate the prognostic factors for local control based on a large population under a unified treatment policy. RESULTS: Between 1970 and 1998, 433 patients with stage II tongue squamous cell carcinoma were treated by low-dose-rate brachytherapy. This series included 277 patients treated with a linear source with a minimum follow-up of 3 years. A spacer was introduced in 1987. The primary local control rates were 85.6%. CONCLUSION: In the multivariate analysis, an invasive growth pattern was a significant factor for local recurrence. The disease-related survival was influenced by old age and an invasive growth pattern. A spacer lowered mandibular bone complications. The growth pattern was the most important factor for recurrence. Brachytherapy was associated with a high cure rate and the use of spacers brought about good quality of life (QOL).