Results Of External Beam Radiotherapy Research Articles

External beam radiotherapy inhibits stent related granulation hyperplasia in rabbit trachea

Endobronchial stent exacerbates the formation of granulation tissue. Radiotherapy maybe a durable treatment option for granulation hyperplasia. In this study, we explore the results of external beam radiotherapy (EBRT) for granulation hyperplasia after airway stent placement. A total of 30 New Zealand rabbits were assigned in three groups, Control group (n = 12), low dosage (LD, 12 Gy in 4 fractions and twice a week) group (n = 9) and high dosage (HD, 20 Gy in 4 fractions and twice a week) group (n = 9). Post-stenting 1 week, LD and HD group started to receive EBRT. Bronchoscopy, Haematoxylin–eosin (HE), Masson’s trichrome (MTS), Safranin O (SO) and immunohistochemical (IHC) staining protocols were performed to evaluate the histopathological changes of trachea. A total of 30 stents were successfully implanted in 30 rabbits. No procedure-related death and complications happened. Post-stenting 4 w, 8 w and 12 w, the ventilate area ratio (VAR) and qualitative histological scoring (QHS) in the LD group and HD group lower than the Control group. Post-stenting 12w, the immunohistochemical results revealed that the positive percentage of TGF-β and VEGF in the LD group and HD group were lower than the Control group. In conclusion, the present study investigated the efficacy of EBRT in reducing stent related granulation tissue formation in the rabbit trachea. Higher dosage EBRT with a better result in inhibiting granulation hyperplasia.

The role of interventional radiotherapy (brachytherapy) in nasopharynx tumors: A systematic review.

Nasopharyngeal cancers (NPC) are very aggressive, and the recurrence rate after radical therapy is high. This study aimed to evaluate the efficacy of brachytherapy (BT) also called interventional radiotherapy (IRT) in primary NPC in comparison with external beam radiotherapy (EBRT) alone. A systematic search was performed in Scopus, Cochrane, and PubMed databases. Clinical query based on PICO framework was as follows: In patients with NPC (P), is EBRT plus IRT (I) superior to EBRT alone (C) in terms of local control (LC) and toxicity (O)? Full articles evaluating the efficacy of IRT as a boost after EBRT in patients with NPC were considered. Eight papers, including 1,320 patients fulfilled the inclusion criteria. The median 5-year LC for IRT group and no-IRT group was 98% (range, 95.8-100%) and 86% (range, 80.2-91%), respectively; the median 5-year overall survival (OS) for IRT group and no-IRT group was 93.3% (range, 89.2-97.5%) and 82.9% (range, 74.8-91.1%), respectively; the median 5-year DFS for IRT group and no-IRT group was 94.2% (range, 92.5-96%) and 83.9% (range, 73.3-94.6%), respectively; the median 5-year cancer-specific survival (CSS) for IRT group and no-IRT group was 96% (range, 94.5-97.5%) and 88.2% (range, 83.4-93.1%), respectively. G1-2 and G3-4 toxicities were similar in some articles, or significantly lower in patients treated with IRT in other papers. Data suggest that IRT may improve results of external beam radiotherapy in primary NPCs, especially when using new technologies.

A comparative study of treatment on portal vein tumor thrombosis in hepatocellular carcinoma with stereotactic radiotherapy versus three-dimensional conformal radiotherapy

Background: Portal venous tumor thrombosis (PVTT) in patients with hepatocellular carcinoma (HCC) is a poor prognostic factor, with median survival values ranging from 2 to 4 months, when untreated. Sorafenib has been used as a systemic therapy for advanced HCC patients with PVTT; however, its local effects are limited. We report the results of external beam radiotherapy for PVTT, including stereotactic radiotherapy. Methods: Fifty consecutive HCC patients with PVTT who underwent external beam radiotherapy were investigated at our institution between January 2004 and December 2019. Results: The median age of the patients was 71 years (range: 39–87). The patients were predominantly male (80%) who underwent three-dimensional conformal radiation therapy (82%). The Child-Pugh score was class A in 30(60%) patients and class B in 20(40%) patients. The median overall survival (OS) was 12.6 months (95% confidence interval [CI]: 7.2–18.2) and the 1-year overall survival rate for all patients was 52.3% (95% [CI]: 36.9 - 65.6). A favorable objective response rate was achieved in the stereotactic radiotherapy group (78%) compared to the three-dimensional conformal radiation therapy group (39%). Severe acute adverse events of grade 3 or higher were not observed. Conclusions: The present study demonstrated the feasibility and efficacy of external beam radiotherapy for PVTT in patients with HCC.

Long-term Results of External Beam Radiotherapy for Prostate Cancer with Prostate-specific Antigen of More Than 50 ng/ml and Without Evidence of Lymph Node or Distant Metastasis.

To evaluate long-term treatment outcomes of external beam radiotherapy for prostate cancer with a pretreatment prostate-specific antigen (PSA) level of more than 50 ng/ml and without evidence of lymph node or distant metastasis. Definitive radiotherapy of 66 Gy or 72 Gy in combination with androgen deprivation therapy (ADT) was performed. PSA relapse-free survival (PRFS), distant metastasis-free survival (DMFS), cause-specific survival (CSS), and overall survival (OS) were evaluated. The impact of prognostic factors on PRFS, DMFS, CSS, and OS was analyzed in univariate and multivariate analyses. One hundred twenty patients with a median follow-up period of 92.6 months were analyzed in this study. The median duration of ADT was 11.0 months. The 5- and 8-year PRFS rates in all patients were 65.1% and 48.5%, respectively. The 8-year DMFS, CSS, and OS rates in all patients were 84.0%, 93.4%, and 81.6%, respectively. Both in univariate and multivariate analyses, Gleason score (GS) and radiotherapy dose were significant prognostic factors (p=0.015 and 0.001). There was no significant difference between each prognostic factor in DMFS, CSS, and OS. We might have indicated the significance of definitive radiotherapy even for prostate cancer with PSA of more than 50 ng/ml and without evidence of metastasis.

Results of external beam radiotherapy for diffuse choroidal hemangiomas in Sturge-Weber syndrome.

The Sturge-Weber Syndrome (SWS) is a phacomatosis which include facial nevus flammeus, glaucoma, diffuse choroidal hemangioma, and leptomeningeal hemangiomatosis. External beam radiotherapy (EBRT) using photons was used to treat retinal detachment. We investigate the anatomical and functional results in a long-term basis. Retrospective review of SWS patients treated by EBRT (20 Gy in 10 fractions) for an exudative diffuse choroidal hemangioma. Visual acuity, B-scan tumor thickness, size of retinal detachment, intra-ocular pressure, and hypotonic treatment were collected before EBRT, 1 year after, and at the latest news. Twenty-five patients (26 eyes) were treated between 2001 and 2014. Retinal detachment including the macula was found among twenty-six eyes before treatment. The average follow-up time was 47 months. The mean tumor thickness was initially 4.5 mm, 2.8 mm at first year, and 2.7 mm at the last visit. The retina was reattached at the last visit for all eyes except two. The visual acuity was stable or better for 20 eyes (p = 0.02). Four patients developed mild cataract during the follow-up. EBRT using 20 Gy in 10 fractions is efficient, decreases tumor thickness, reattaches the retina, and stabilizes visual acuity. In the long term, retinal reattachment allows ocular conservation by preventing phthisis bulbi.

Clinical results of external beam radiotherapy alone with a concomitant boost program or with conventional fractionation for cervical cancer patients who did not receive intracavitary brachytherapy

Department of Radiation Oncology, Hiroshima City Hospital, 7-33 Moto-machi, Naka-ku, Hiroshima 730-8518, Japan Department of Radiology, Higashi-Hiroshima Medical Center, 513 Jige, Saijo-cho, Higashi-Hiroshima 739-0041, Japan Department of Obstetrics and Gynecology, Hiroshima City Asa Hospital, 2-1-1 Kabe-minami, Asakita-ku, Hiroshima 731-0293, Japan Department of Radiation Oncology, Hiroshima City Asa Hospital, 2-1-1 Kabe-minami, Asakita-ku, Hiroshima 731-0293, Japan Hiroshima Heiwa Clinic, State of the Art Treatment Center, 1-31 Kawara-machi, Hiroshima 730-0856, Japan *Corresponding author. Tel: +81(82)221-2291; Fax: +81(82)223-5514; Email: mkanji@fg8.so-net.ne.jp

Clinical results of external beam radiotherapy alone with a concomitant boost program or with conventional fractionation for cervical cancer patients who did not receive intracavitary brachytherapy

A combination of external beam radiotherapy (EBRT) and intracavitary brachytherapy (ICBT) is well established as the standard radical radiotherapy (RT) for cervical cancer. However, it is sometimes necessary to perform EBRT alone for patients where ICBT is not feasible. For these patients, we initiated EBRT alone with three-dimensional conformal radiotherapy (3DCRT). The purpose of this study is to evaluate the results of EBRT alone without ICBT for patients with cervical cancer. Sixteen patients were treated with EBRT alone between 2002 and 2009. There were three stage IIB, six stage IIIB and seven patients with stage IVA disease. A total of 10 patients were treated with a median dose of 66 Gy with a median overall treatment time (OTT) of 40 days delivered by a concomitant boost (CCB), and a median dose of 60 Gy with a median OTT of 47 days was administered for six patients by conventional fractionation (CF). The 3-year overall survival (OAS) and local control (LC) rates were 43.8% and 75.0%, respectively. The 3-year LC rate was 90.0% for the CCB group, 50.0% for the CF group (P = 0.0692); 100% for OTT ≤42 days, 42.9% for OTT ≥43 days (P = 0.0095). No severe acute and late adverse effects were encountered for any of the patients. These outcomes suggest that EBRT with a CCB program may be a promising radical treatment for cervical cancer that provides better LC with minimal complications, especially in cases where ICBT cannot be performed.

Single blind randomized Phase III trial to investigate the benefit of a focal lesion ablative microboost in prostate cancer (FLAME-trial): study protocol for a randomized controlled trial

BackgroundThe treatment results of external beam radiotherapy for intermediate and high risk prostate cancer patients are insufficient with five-year biochemical relapse rates of approximately 35%. Several randomized trials have shown that dose escalation to the entire prostate improves biochemical disease free survival. However, further dose escalation to the whole gland is limited due to an unacceptable high risk of acute and late toxicity. Moreover, local recurrences often originate at the location of the macroscopic tumor, so boosting the radiation dose at the macroscopic tumor within the prostate might increase local control. A reduction of distant metastases and improved survival can be expected by reducing local failure. The aim of this study is to investigate the benefit of an ablative microboost to the macroscopic tumor within the prostate in patients treated with external beam radiotherapy for prostate cancer.Methods/DesignThe FLAME-trial (Focal Lesion Ablative Microboost in prostatE cancer) is a single blind randomized controlled phase III trial. We aim to include 566 patients (283 per treatment arm) with intermediate or high risk adenocarcinoma of the prostate who are scheduled for external beam radiotherapy using fiducial markers for position verification. With this number of patients, the expected increase in five-year freedom from biochemical failure rate of 10% can be detected with a power of 80%. Patients allocated to the standard arm receive a dose of 77 Gy in 35 fractions to the entire prostate and patients in the experimental arm receive 77 Gy to the entire prostate and an additional integrated microboost to the macroscopic tumor of 95 Gy in 35 fractions. The secondary outcome measures include treatment-related toxicity, quality of life and disease-specific survival. Furthermore, by localizing the recurrent tumors within the prostate during follow-up and correlating this with the delivered dose, we can obtain accurate dose-effect information for both the macroscopic tumor and subclinical disease in prostate cancer. The rationale, study design and the first 50 patients included are described.Trial registrationThis study is registered at ClinicalTrials.gov: NCT01168479

3D-CT implanted interstitial brachytherapy for T2b nasopharyngeal carcinoma

BackgroundTo compare the results of external beam radiotherapy in combination with 3D- computed tomography (CT)-implanted interstitial high dose rate brachytherapy (ERT/3D-HDR-BT) versus conventional external beam radiotherapy (ERT) for the treatment of stage T2b nasopharyngeal carcinoma (NPC).MethodsForty NPC patients diagnosed with stage T2b NPC were treated with ERT/3D-HDR-BT under local anesthesia. These patients received a mean dose of 60 Gy, followed by 12-20 Gy administered by 3D-HDR-BT. Another 101 patients diagnosed with non-metastatic T2b NPC received a mean dose of 68 Gy by ERT alone during the same period.ResultsPatients treated with ERT/3D-HDR-BT versus ERT alone exhibited an improvement in their 5-y local failure-free survival rate (97.5% vs. 80.2%, P = 0.012) and disease-free survival rate (92.5% vs. 73.3%, P = 0.014). Using multivariate analysis, administration of 3D-HDR-BT was found to be favorable for local control (P = 0.046) and was statistically significant for disease-free survival (P = 0.021). The incidence rate of acute and chronic complications between the two groups was also compared.ConclusionsIt is possible that the treatment modality enhances local control due to improved conformal dose distributions and the escalated radiation dose applied.

Long Term Follow-up Results of External Beam Radiotherapy as Primary Treatment for Retinoblastoma

The authors reviewed their experiences of external beam radiotherapy (EBR) as an initial treatment in retinoblastoma patients to determine its long-term effect on subsequent tumor control and complications. A total of 32 eyes in 25 patients that underwent EBR for retinoblastoma were reviewed retrospectively. The patients consisted of 21 boys and 4 girls of median age at treatment of 7.1 months. Radiation doses ranged from 35 to 59.4 Gy. The 10-yr ocular and patient survivals were 75.4% and 92.3%, respectively. Nine of the 32 eyes progressed; 7 of these were enucleated and 2 were salvaged by focal treatment. According to the Reese-Ellsworth classification, 4 of 5 eyes of Group II, 13 of 16 Group III eyes, 2 of 4 Group IV eyes, and 5 of 7 Group V eyes were retained, and of the 32 eyes, 13 had visual acuity better than 20/200. Eleven patients experienced a radiation-induced complication. No patient developed a second malignancy during follow-up. Despite the limited number of patients enrolled, EBR may provide a mean of preserving eyeball and vision for some advanced lesions.

External Beam Radiotherapy for Clinically Localized Hormone-Refractory Prostate Cancer: Clinical Significance of Nadir Prostate-Specific Antigen Value Within 12 Months

To analyze retrospectively the results of external beam radiotherapy for clinically localized hormone-refractory prostate cancer and investigate the clinical significance of nadir prostate-specific antigen (PSA) value within 12 months (nPSA12) as an early estimate of clinical outcomes after radiotherapy. Eighty-four patients with localized hormone-refractory prostate cancer treated with external beam radiotherapy were retrospectively reviewed. The total radiation doses ranged from 30 to 76 Gy (median, 66 Gy), and the median follow-up period for all 84 patients was 26.9 months (range, 2.7-77.3 months). The 3-year actuarial overall survival, progression-free survival (PFS), and local control rates in all 84 patients after radiotherapy were 67%, 61%, and 93%, respectively. Although distant metastases and/or regional lymph node metastases developed in 34 patients (40%) after radiotherapy, local progression was observed in only 5 patients (6%). Of all 84 patients, the median nPSA12 in patients with clinical failure and in patients without clinical failure was 3.1 ng/mL and 0.5 ng/mL, respectively. When dividing patients according to low (<0.5 ng/mL) and high (>or=0.5 ng/mL) nPSA12 levels, the 3-year PFS rate in patients with low nPSA12 and in those with high nPSA12 was 96% and 44%, respectively (p < 0.0001). In univariate analysis, nPSA12 and pretreatment PSA value had a significant impact on PFS, and in multivariate analysis nPSA12 alone was an independent prognostic factor for PFS after radiotherapy. External beam radiotherapy had an excellent local control rate for clinically localized hormone-refractory prostate cancer, and nPSA12 was predictive of clinical outcomes after radiotherapy.

Wound healing on the lower leg after radiotherapy or cryotherapy of Bowen's disease and other malignant skin lesions.

To investigate lower leg wound healing after treatment of skin tumours, the results of external beam radiotherapy were assessed for 141 lesions in 91 patients. Poor healing or failure to heal occurred in 33%, and was related to the age of the patients, the diameter of the radiotherapy field, and the dose and energy of radiotherapy used. No effect of fractionation on healing was apparent, but only 14% of patients were exposed to regimens with a nominal standard dose of over 1800 rets. Age > 90 years, field diameter > 4 cm and dose > 3000 cGy were all associated with a risk of impaired healing of over 50%. The most frequent single diagnosis (59 lesions) in the radiotherapy patients was Bowen's disease. The results of wound healing in these patients were compared with the results of cryotherapy to 82 lower leg Bowen's disease lesions in 49 dermatology patients. Only 2% of the cryotherapy lesions failed to heal compared with 20% of the radiotherapy wounds, although 6% of cryotherapy cases had local recurrence compared with none in the radiotherapy group. Serial overlapping cryotherapy fields of up to 2 cm diameter were shown to be a valid treatment option for Bowen's disease, as no patients had therapy-related failure to heal. To avoid the requirement for potentially more difficult post-radiotherapy salvage surgery, intra-epidermal non-invasive skin tumours > 4 cm in diameter on the lower leg are probably initially best treated by a primary surgical procedure or by staged cryotherapy. Invasive carcinoma of > 4 cm diameter is best treated by surgical excision.(ABSTRACT TRUNCATED AT 250 WORDS)

Six fractions per week of external beam radiotherapy and high-dose-rate brachytherapy for carcinoma of the uterine cervix: A phase I/II study

This study evaluated the treatment results of external beam radiotherapy administered in six fractions per week and high-dose-rate (HDR) brachytherapy for the treatment of cervical cancer. From July 2000 to July 2003, 43 patients were enrolled in this study. The patients received 45 Gy from a 10-MV photon beam using four-field box or anterior-posterior beams. Parametrial regions and the pelvic side walls were boosted with up to 50.4 Gy using a midline block. The daily fraction dose was 1.8 Gy administered in six-weekly fractions, from Monday to Saturday. HDR brachytherapy was also delivered at doses of 24 Gy to point A in six fractions twice a week. The median follow-up time was 37 months (range, 9-60 months). The median overall treatment time was 51 days for all patients (range, 44-62 days). Thirty-four patients (79.1%) achieved complete remission and 8 (18.6%) achieved partial remission after radiotherapy. Locoregional recurrence occurred in 5 patients (11.6%), and a distant metastasis was encountered in 6 patients (13.9%). The 3-year overall survival, locoregional, and distant metastasis-free survival rates were 74.7%, 87.8%, and 84.7%, respectively. Grade 2 and 3 late rectal complications were encountered in 3 (6.5%) and 1 (2.2%), respectively. There were no Grade 3 late bladder complications. Six fractions per week of external beam radiotherapy and HDR brachytherapy is an effective treatment for patients with a carcinoma of the uterine cervix and can be used as a possible alternative to concomitant chemoradiotherapy in elderly patients or in patients with co-morbidity.

Long-term results of definitive radiotherapy for stage I esophageal cancer

To analyze retrospectively the long-term results of external beam radiotherapy (RT) with or without intraluminal brachytherapy (ILBT) for patients with Stage I esophageal cancer. A total of 34 patients with esophageal squamous cell carcinoma, clinically diagnosed as having Stage I disease, were treated with definitive RT, with or without ILBT. The median age was 69 years. Seven patients were treated with external beam RT alone (median, 64 Gy), and 27 were treated with external beam RT (median, 52 Gy) plus ILBT (8-12 Gy in two to three fractions). The 5-year overall survival, local relapse-free survival, and cause-specific survival rate was 58.9%, 68.4%, and 80.0%, respectively, with a median follow-up of 61 months. Of 9 patients with local recurrence after initial therapy, 7 were successfully treated, and the 5-year cumulative rate of esophagectomy was 19.6%. The 2-year local relapse-free rate for patients with and without ILBT was 79.1% and 53.6%, respectively. Although local recurrence was frequent within 2 years, the disease-specific survival rate was high owing to effective salvage therapy. Definitive RT is a reasonable treatment option for highly comorbid and elderly patients with Stage I esophageal cancer. The role of ILBT needs to be clarified.

How low is the α/β ratio for prostate cancer?

Purpose Recently, low α/β values of 1.2 and 1.5 Gy for prostate tumors have been derived from clinical results of external beam radiotherapy and of permanent implants of 125I and 103Pd. In the analyses the contributions of tumor repopulation, and edema as a result of inserting radioactive seeds in the prostate, have been ignored. In this paper we reanalyzed the clinical data and introduced the contribution of repopulation and edema. Methods and materials The linear quadratic–biologically effective dose model was used for reanalysis. In this model, the influence of repopulation and edema has been taken into account. The biologically effective dose was calculated as a function of α/β for 2 brachytherapy regimens with 125I and 103Pd and 2 fractionated treatments, and for different half-times for repair of sublethal damage for the brachytherapy regimens. Results We have found a plausible α/β value of 3.1 to 3.9 Gy, an α value of 0.1 to 0.15 Gy −1, and a half-time of repair of about 0.5 h. Conclusions It seems now that the α/β value is low, 3.1–3.9 Gy, but not as low as the 1.2 and 1.5 Gy reported earlier.

External beam radiation therapy in the treatment of patients with extranodal stage IA non-Hodgkin's lymphoma.

The purpose of this report was to study the results of external beam radiotherapy for patients with extranodal stage IA non-Hodgkin's lymphoma (NHL). A retrospective review was carried out on 27 patients seen between 1984 and 1998 with stage IA NHL of extranodal sites, and followed up for a minimum of 1 year. Sites involved included eye/orbit (seven), parotid (five), breast (four), Waldeyer ring (four), thyroid (three), other head and neck (two), stomach (one), and prostate (one). All patients had biopsy-proven disease and underwent staging workup to rule out other sites of disease. Histologic analysis revealed 16 patients with low-grade NHL, 9 with intermediate-grade, and 2 with high-grade. Ten patients received chemotherapy before radiation therapy, and eight of them had a complete response. The remaining 17 patients were treated with external beam radiation therapy alone. Radiation was directed to the involved field at 1.8 Gy to 2.0 Gy per fraction to a median dose of 40 Gy (range: 20-50.4 Gy). The median patient age was 71 years (range: 39-85 years); 55% were female, and 45% were male. A complete response was attained in all 27 patients after radiation therapy. There were five failures (all in uninvolved distant sites), and two deaths during the follow-up. Median disease free survival (DFS) and overall survival (OS) have not been reached. The 5-year DFS and OS are 85% and 94%, respectively. Older age at presentation showed a trend toward worse outcome (p = 0.07), but because of the relatively few events, other factors (radiation dose, grade of disease, sex, or the use of chemotherapy) showed no statistical differences among the patients. External beam radiation therapy is a highly effective treatment for stage IA NHL found in extranodal sites.

Postoperative radiotherapy for intracranial ependymoma: analysis of prognostic factors and patterns of failure.

The long-term results of external beam radiotherapy following surgical resection in patients with intracranial ependymomas were evaluated to identify the prognostic factors and the pattern of recurrence. Between June 1961 and January 1999, 48 patients with intracranial ependymoma were treated with external beam irradiation with >40 Gy following surgery. Total doses of 40.5-63.4Gy were delivered to the tumor site in 22-46 fractions over 33-101 days. Six patients with spinal deposit or positive cerebrospinal fluid cytology received whole spinal axis irradiation, and 4 patients received prophylactic spinal irradiation. The median follow-up of surviving patients was 110 months. The 10-year overall and relapse-free survival rates were 47% and 42%, respectively. In multivariate analysis, female gender, lower tumor grade and total resection were found to be associated with better relapse-free survival. Twenty of 26 recurrences developed at the primary tumor site (inside the irradiation field), two at the unirradiated cerebellum and spinal cord, and four at the spinal cord without intracranial failure. Only one of 34 patients with supratentorial tumors developed isolated spinal metastasis, whereas 3 of 14 patients with infratentorial tumors did so. Regarding the late neurotoxicity of radiotherapy, one of the 15 long-term (>4 years) survivors whose psychosocial status could be evaluated showed marked cognitive impairment. It was suggested that the use of new treatment strategies to improve local control would be warranted, and that prophylactic whole spinal axis irradiation appeared to be of more benefit in patients with infratentorial tumors than in those with supratentorial tumors.

Results of external beam radiotherapy alone for incompletely resected carcinoma of rectosigmoid or rectum: peter maccallum cancer institute experience 1981–1990

Purpose: To study the results of external beam radiotherapy treatment for incompletely resected nonmetastatic rectosigmoid and rectal carcinoma. Methods and Materials: A retrospective review was carried out of all patients (57) presenting to Peter MacCallum Cancer Institute from 1981 to 1990 with incompletely resected nonmetastatic rectosigmoid or rectal cancer who were treated with external beam radiotherapy. Three radiotherapy schedules were used: radical (50 to 60 Gy, 27 patients), high-dose palliative (45 Gy, 25 patients), and low-dose palliative (less than 45 Gy, 5 patients). Symptomatic response, overall survival, and the effect of prognostic factors on treatment outcome were evaluated. The median follow-up period for survivors was 49 months. Results: Symptomatic response rates were 83% and 79% for the radical and high-dose palliative groups respectively. The estimated median survival time from presentation for all patients was 16.4 months (radical 26.1 months, high-dose palliative 15.7 months). Patients with microscopic residual disease survived significantly longer than patients with macroscopic residual disease (estimated median survival time 30.7 months vs. 14.3 months, p = 0.013). Conclusions: No dose response effect was seen between the radical group and high-dose palliative group. Microscopic residual disease at presentation was the only significant predictor of better survival. The conventionally fractionated course of 50 to 60 Gy was not significantly better in terms of palliation and overall survival than a shorter palliative course of 45 Gy. In future, preoperative chemoradiation should improve outcome by reducing the number of patients with incompletely resected cancer.

Clinical results of unconventional fractionation radiotherapy in central nervous system tumors.

Malignant brain tumors (primary and metastatic) are apparently resistant to most therapeutic efforts. Several randomized trials have provided evidence supporting the efficacy of radiation therapy. Attempts at improving the results of external beam radiotherapy include altered fractionation, radiation sensitizers and concomitant chemotherapy. In low-grade gliomas, all clinical studies with radiotherapy have employed conventional dose fractionation regimens. In high-grade gliomas, hypofractionation schedules represent effective palliative regimens in poor prognosis subsets of patients; short-term survival in these patients has not allowed to evaluate late toxicity. In tumors arising within the central nervous system, hyperfractionated irradiation exploits the differences in repair capacity between tumour and late responding normal tissues. It may allow for higher total dose and may result in increased tumor cell kill. Accelerated radiotherapy may reduce the repopulation of tumor cells between fractions. It may potentially improve tumor control for a given dose level, provided that there is no increase in late normal tissue injury. In supratentorial malignant gliomas, superiority of accelerated hyperfractionated over conventionally fractionated schedules was observed in a randomized trial; however, the gain in survival was less than 6 months. At present no other randomized trial supports the preferential choice for altered fractionation irradiation. Also in pediatric brainstem tumors there are no data to confirm the routine use of hyperfractionated irradiation, and significant late sequelae have been reported in the few long-term survivors. Shorter treatment courses with accelerated hyperfractionated radiotherapy may represent a useful alternative to conventional irradiation for the palliation of brain metastases. Different considerations have been proposed to explain this gap between theory and clinical data. Patients included in dose/effect studies are not stratified by prognostic factors and other treatment-related parameters. This observation precludes any definite conclusion about the relative role of conventional and of altered fractionation. New approaches are currently in progress. More prolonged radiation treatments, up to higher total doses, could delay time to tumor progression and improve survival in good prognosis subsets of patients; altered fractionation may be an effective therapeutic tool to achieve this goal.

1155 - Primary advanced, recurrent and metastatic malignant melanoma clinical update on 20-year results of external beam radiotherapy

1155 - Primary advanced, recurrent and metastatic malignant melanoma clinical update on 20-year results of external beam radiotherapy