Monte Carlo as quality control tool of stereotactic body radiation therapy treatment plans.

PURPOSE/OBJECTIVE: The objective of this study was to verify the accuracy of treatment plans of stereotactic body radiation therapy (SBRT) and to verify the feasibility of the use of Monte Carlo (MC) as quality control (QC) on a daily basis. MATERIAL/METHODS: Using EGSnrc, a MC model of Agility™ linear accelerator was created. Various measurements (Percentage depth dose (PDD), Profiles and Output factors) were done for different fields sizes from 1x1 up to 40x40 (cm2). An iterative model optimization was performed to achieve adequate parameters of MC simulation. 40 SBRT patient's dosimetry plans were calculated by Monaco™ 3.1.1. CT images, RT-STRUCT and RT-PLAN files from Monaco™ being used as input for Moderato MC code. Finally, dose volume histogram (DVH) and paired t-tests for each contour were used for dosimetry comparison of the Monaco™ and MC. RESULTS: Validation of MC model was successful, as <2% difference comparing to measurements for all field's sizes. The main energy of electron source incident on the target was 5.8 MeV, and the full width at half maximum (FWHM) of Gaussian electron source were 0.09 and 0.2 (cm) in X and Y directions, respectively. For 40 treatment plan comparisons, the minimum absolute difference of mean dose of planning treatment planning (PTV) was 0.1% while the maximum was 6.3%. The minimum absolute difference of Max dose of PTV was 0.2% while the maximum was 8.1%. CONCLUSION: SBRT treatment plans of Monaco agreed with MC results. It possible to use MC for treatment plans verifications as independent QC tool.

Primary breast lymphoma: patient profile, outcome and prognostic factors. A multicentre Rare Cancer Network study.

BACKGROUND: To asses the clinical profile, treatment outcome and prognostic factors in primary breast lymphoma (PBL). METHODS: Between 1970 and 2000, 84 consecutive patients with PBL were treated in 20 institutions of the Rare Cancer Network. Forty-six patients had Ann Arbor stage IE, 33 stage IIE, 1 stage IIIE, 2 stage IVE and 2 an unknown stage. Twenty-one underwent a mastectomy, 39 conservative surgery and 23 biopsy; 51 received radiotherapy (RT) with (n = 37) or without (n = 14) chemotherapy. Median RT dose was 40 Gy (range 12-55 Gy). RESULTS: Ten (12%) patients progressed locally and 43 (55%) had a systemic relapse. Central nervous system (CNS) was the site of relapse in 12 (14%) cases. The 5-yr overall survival, lymphoma-specific survival, disease-free survival and local control rates were 53%, 59%, 41% and 87% respectively. In the univariate analyses, favorable prognostic factors were early stage, conservative surgery, RT administration and combined modality treatment. Multivariate analysis showed that early stage and the use of RT were favorable prognostic factors. CONCLUSION: The outcome of PBL is fair. Local control is excellent with RT or combined modality treatment but systemic relapses, including that in the CNS, occurs frequently.

Boost radiotherapy in young women with ductal carcinoma in situ: a multicentre, retrospective study of the Rare Cancer Network.

BACKGROUND: Outcome data in young women with ductal carcinoma in situ (DCIS) are rare. The benefits of boost radiotherapy in this group are also unknown. We aimed to assess the effect of boost radiotherapy in young patients with DCIS. METHODS: We included 373 women from 18 institutions who met the following inclusion criteria: having tumour status Tis and nodal status (N)0, age 45 years or younger at diagnosis, and having had breast-conserving surgery. 57 (15%) patients had no radiotherapy after surgery, 166 (45%) had radiotherapy without boost (median dose 50 Gy [range 40-60]), and 150 (40%) had radiotherapy with boost (60 Gy [53-76]). The primary outcome was local relapse-free survival. FINDINGS: Median follow-up was 72 months (range 1-281). 55 (15%) patients had local relapse. Local relapse-free survival at 10 years was 46% (95% CI 24-67) for patients given no radiotherapy, 72% (61-83) for those given radiotherapy without boost, and 86% (78-93) for those given radiotherapy and boost (difference between all three groups, p<0.0001). Age, margin status, and radiotherapy dose were significant predictors of local relapse-free survival. Compared with patients who had no radiotherapy, those who had radiotherapy had a decreased risk of local relapse (without boost, hazard ratio 0.33 [95% CI 0.16-0.71], p=0.004; with boost, 0.15 [0.06-0.36], p<0.0001). INTERPRETATION: In the absence of randomised trials, boost radiotherapy should be considered in addition to surgery for breast-conserving treatment for DCIS.

Treatment of squamous cell anal canal carcinoma (SCACC) with pulsed dose rate brachytherapy: a retrospective study.

BACKGROUND AND PURPOSE: To evaluate the results of pulsed dose rate brachytherapy (PDR) in SCACC. MATERIAL AND METHODS: From 1996 to 2002, 71 patients (pts) with SCACC were treated with PDR brachytherapy. The median age was 61.2 years (35-88), with a sex ratio of 1 M/6.5 F. The TNM classification was: 14 T1, 41 T2, 15 T3 and 1 T4, 52 N0, 13 N1, 3 N2 and 3 N3. All the pts were M0. Treatment started with external beam irradiation to the posterior pelvis (mean dose: 45.5 Gy). Forty-seven patients received chemotherapy (neoadjuvant/concomitant or both). After an interval of 2-6 weeks, PDR interstitial brachytherapy was performed. The mean dose was 17.8 Gy to the 85% reference isodose of the Paris system. RESULTS: Treatment was interrupted in only one pt. With a median follow-up of 28.5 months, 2-year actuarial overall survival was 90%. Fourteen relapses occurred (four distant, three regional, and seven local). Ten patients developed a grade III complication (Lent Soma scale) and two a grade IV complication (colostomy or abdominal perineal resection for necrosis). CONCLUSION: PDR appears to be an effective treatment for SCACC. It is capable of reproducing the results usually observed with continuous LDR.

[Metastasis of a lumbosacral ependymoma with very long disease-free survival: a case report and review of the literature]. / Métastase d'un épendymome lombosacré avec très long intervalle libre: cas clinique et revue de la littérature.

Ependymoma is rare glial tumour of the central nervous system and is considered to be low-grade. The lumbosacral location of spinal ependymoma is the most common. Prognosis of ependymomas is dependent on tumour location, histological subtype and differentiation, extent of the tumour and of the completeness of the surgical resection. One of the characteristics of this kind of tumour is to present the possibility of a seeding of the entire cerebrospinal axis, by the way of cerebrospinal liquid. We describe the case of a young male patient operated by incomplete resection of a lumbar ependymoma. Six months later, the patient's symptoms reappeared and an external radiotherapy at curative doses and chemotherapy were delivered. Evolution of the remaining tumour was diagnosed 6 years after at the primary site and operated by large incomplete resection. A second session of radiotherapy was therefore administered. Twenty-four years after this episode, cervical pain and gait troubles appear. Complete imaging study concluded to a cervical extramedullary intradural tumour and to the persistence of the primary lumbosacral tumour. Macroscopical complete resection of the cervical tumour was performed and pathological findings concluded to a metastasis of his lumbar ependymoma. External radiotherapy was delivered on this site with a total dose of 50 Gy. Eight years after this episode, the patient is alive without evidence of distant disease. The primary lumbosacral ependymoma is stable. Ependymomas are often recurrent at the primary site, but can seed on the entire cerebrospinal axis. Awareness of such aberrant tumoral behaviour, even after such a long disease free interval, may warrant more careful follow-up of patients with this diagnosis.

Postoperative adjuvant gemcitabine and concurrent radiation after curative resection of pancreatic head carcinoma: a phase II study.

PURPOSE: The addition of radiation to adjuvant 5-fluorouracil for the treatment of pancreatic cancer has not yet shown any definite benefit. Gemcitabine (GEM) has potential activity in advanced pancreatic cancer and is a powerful radiosensitizer. We evaluated the feasibility of postoperative administration of GEM alone, followed by concurrent GEM and irradiation (RT) after curative resection for pancreatic adenocarcinoma. METHODS AND MATERIALS: GEM 1000 mg/m(2) on Days 1 and 8 every 21 days for three courses was given within 8 weeks after surgery and was followed by GEM 300 mg/m(2) weekly +40 Gy in a split course. Twenty-two patients (median age 59 years, range 39-74, Performance Status 0-1) with Stage II and III curatively resected pancreatic head adenocarcinoma were included. RESULTS: For GEM alone, all patients received the three planned courses, with dose reductions in 7 (32%) of 22 patients. All patients, except two, completed full chemoradiation; one received only 20 Gy because of both World Health Organization Grade 4 vomiting and thrombopenia and the other stopped RT after 32 Gy because of early disease progression. No reduction in GEM during RT was necessary; no toxic death was noted; and World Health Organization Grade 3-4 hematologic and nonhematologic toxicities occurred in 8 (36%) and 7 (nausea, vomiting) (32%) of 22 patients respectively. No late toxicity developed. After a median follow-up of 15 months, 11 patients were alive, and 2 patients had died of causes unrelated to their disease or toxicity, The median disease-free survival and overall survival was 6 and 15 months, respectively. CONCLUSION: This adjuvant regimen was well tolerated and can be easily administered after curative surgery for pancreatic cancer. Its intensification with continuous RT is currently being investigated.