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Purpose: To report a retrospective study concerning the impact of fused 18F-fluoro-deoxy-D-glucose (FDG)-hybrid positron emission tomography (PET) and CT images on three-dimensional conformal radiotherapy planning for patients with non-small-cell lung cancer., Methods and Materials: A total of 101 patients consecutively treated for Stage I-III non-small-cell lung cancer were studied. Each patient underwent CT and FDG-hybrid PET for simulation treatment in the same treatment position. Images were coregistered using five fiducial markers. Target volume delineation was initially performed on the CT images, and the corresponding FDG-PET data were subsequently used as an overlay to the CT data to define the target volume., Results: 18F-fluoro-deoxy-D-glucose-PET identified previously undetected distant metastatic disease in 8 patients, making them ineligible for curative conformal radiotherapy (1 patient presented with some positive uptake corresponding to concomitant pulmonary tuberculosis). Another patient was ineligible for curative treatment because the fused PET-CT images demonstrated excessively extensive intrathoracic disease. The gross tumor volume (GTV) was decreased by CT-PET image fusion in 21 patients (23%) and was increased in 24 patients (26%). The GTV reduction was > or = 25% in 7 patients because CT-PET image fusion reduced the pulmonary GTV in 6 patients (3 patients with atelectasis) and the mediastinal nodal GTV in 1 patient. The GTV increase was > or = 25% in 14 patients owing to an increase in the pulmonary GTV in 11 patients (4 patients with atelectasis) and detection of occult mediastinal lymph node involvement in 3 patients. Of 81 patients receiving a total dose of > or = 60 Gy at the International Commission on Radiation Units and Measurements point, after CT-PET image fusion, the percentage of total lung volume receiving >20 Gy increased in 15 cases and decreased in 22. The percentage of total heart volume receiving >36 Gy increased in 8 patients and decreased in 14. The spinal cord volume receiving at least 45 Gy (2 patients) decreased. Multivariate analysis showed that tumor with atelectasis was the single independent factor that resulted in a significant effect on the modification of the size of the GTV by FDG-PET: tumor with atelectasis (with vs. without atelectasis, p = 0.0001)., Conclusion: The results of our study have confirmed that integrated hybrid PET/CT in the treatment position and coregistered images have an impact on treatment planning and management of non-small-cell lung cancer. However, FDG images using dedicated PET scanners and respiration-gated acquisition protocols could improve the PET-CT image coregistration. Furthermore, the impact on treatment outcome remains to be demonstrated.

Purpose: To study the impact of fused (18)F-fluoro-deoxy-D-glucose (FDG)-hybrid positron emission tomography (PET) and computed tomography (CT) images on conformal radiotherapy planning for esophageal carcinoma patients., Methods and Materials: Thirty-four esophageal carcinoma patients were referred for concomitant radiotherapy and chemotherapy with radical intent. Each patient underwent CT and FDG-hybrid PET for simulation treatment in the same treatment position. PET images were coregistered using five fiducial markers. Target delineation was initially performed on CT images, and the corresponding PET data were subsequently used as an overlay to CT data to define the target volume., Results: (18)F-fluorodeoxy-D-glucose-PET identified previously undetected distant metastatic disease in 2 patients, making them ineligible for curative conformal radiotherapy. The gross tumor volume (GTV) was decreased by CT and FDG image fusion in 12 patients (35%) and increased in 7 patients (21%). The GTV reduction was > or =25% in 4 patients owing to a reduction in the length of the esophageal tumor. The GTV increase was > or =25% with FDG-PET in 2 patients owing to the detection of occult mediastinal lymph node involvement in 1 patient and an increased length of the esophageal tumor in 1 patient. Modifications of the GTV affected the planning treatment volume in 18 patients. Modifications of the delineation of the GTV and displacement of the isocenter of the planning treatment volume by FDG-PET also affected the percentage of total lung volume receiving >20 Gy in 25 patients (74%), with a dose reduction in 12 patients and dose increase in 13., Conclusion: In our study, CT and FDG-PET image fusion appeared to have an impact on treatment planning and management of esophageal carcinoma. The affect on treatment outcome remains to be demonstrated.

Purpose: To evaluate the efficacy and outcome of Linac radiosurgery (RS) as treatment of cerebral arteriovenous malformations (cAVM) in a series of 57 children., Methods and Materials: Between 1984 and 2000, we used Linac radiosurgery to treat 792 patients with cAVM. This series included 57 children (7.2%) under the age of 15 years at the time of RS (range = 7-15 years, median = 12 years). We were able to evaluate 49 of the children (86%) by angiography, 21 boys and 28 girls (sex ratio = 0.75). First symptoms were: hemorrhage, 34 patients (69.4%); seizures, 6 patients (12.5%); headache, 6 patients (12.5%); and progressive neurologic deficit, 1 patient (2.1%). Nidus size ranged from 5 to 50 mm (median = 20 mm). Nidus volume ranged from 0.6 to 16 cc (median = 3.5 cc). Patient distribution according to Spetzler-Martin grade was as follows: Grade 1, n = 5 (11%); Grade 2, n = 18 (35%); Grade 3, n = 21 (40%,); Grade 4, n = 5 (14%); and Grade 5, n = 0%. Twenty-seven patients (55.1%) had other treatment before RS: embolization, n = 14 (31.1%); neurosurgery, n = 9 (20.5%); embolization and neurosurgery, n = 3 (6.1%). RS was performed with the system used for adults. Patients were seated in a Betti armchair. Circular 15 MV X-ray minibeams (6 to 20 mm) were delivered in coronal arcs by a GECGR Saturne 43 Linac. Planification and dosimetry were carried out using the Associated Target Methodology and Dosigray TPS dosimetric systems. The dose at the peripheral isodose (50-70%) ranged from 18 to 28 Gy. Median and mean doses were 25 Gy and 23.8 Gy. Mono-isocentric planification was used in 25 patients (53.2%) and multi-isocentric in 24 patients (2 to 5 isocenters). The overall follow-up ranged from 7 to 172 months (mean 40 months, median 34 months)., Results: The overall rate of obliteration (OR) was 30/49 (61.2%). Mean time to obliteration was 34 months (range = 7 to 172 months). OR varied according to nidus size and volume: OR was 80% for nidus <15 mm, 67% for nidus between 15 and 25 mm, and 42% for nidus >25 mm (p = 0.058). OR was 100% for nidus <1 cc, 73% for nidus between 1 and 4 cc, and 40% for nidus of 4 to 10 cc (p = 0.019). OR according to patient gender was 84.2% for boys and 40% for girls. OR according to minimum dose (Dmin) was 44% for Dmin < 15 Gy (p = 0.01), 89% for D min from 15 to 20 Gy, and 100% for Dmin > 20 Gy (p = 0.01). OR was 62% in nonembolized AVM and 58% in previously embolized AVM (NS). OR according to the number of isocenters was 68.2%, 55.6%, 80%, 50%, and 0% for 1, 2, 3, 4, and 5 isocenters, respectively. After multivariate analysis, only Dmin closely correlated with OR (beta = 0.462; SE = 0.244, p = 0.057). Of the 6 patients with seizures before RS, 5 (80%) were seizure-free without medication after RS. One patient died of pneumonia., Morbidity: Four patients (8.2%) had bleeding after RS at 39, 45, 51, and 59 months. No new neurologic deficit was found during the follow-up period. Twenty-nine patients underwent magnetic resonance imaging. Thirteen patients (44.8%) showed no parenchymal changes. Thirteen patients (44.8%) had Grade 2 changes, that is, T2 hypersignals. Two patients (6.9%) had Grade 3 changes, and 1 patient (3.4%) had Grade 4 "necrosis-like" changes., Conclusion: In our experience, Linac RS has proven to be a safe and effective method to treat cerebral AVM in children <15 years, whether used alone or in association with embolization and/or neurosurgery.

Purpose: To evaluate our data concerning the prognostic factors for locoregional control, survival, late complications, and sphincter conservation in a series of epidermoid cancers of the anal canal without clinical evidence of metastasis., Methods and Materials: Between June 1972 and January 1997, 305 patients were treated with curative-intent radiotherapy (RT). The T stage according to the 1987 International Union Against Cancer classification was T1 in 26, T2 in 141, T3 in 104, and T4 in 34. Forty-nine patients had nodal involvement at presentation. The pretreatment anal function score, according to our in-house system, was 0 for 22 patients, 1 for 182, 2 for 74, 3 for 7, and 4 for 11 patients; for 9 patients, scores were unavailable. The treatment started with external beam radiotherapy (EBRT) in 303 patients (median dose 45 Gy). After a rest period of 4-6 weeks, a boost of 20 Gy was delivered by EBRT in 279 patients and by interstitial (192)Ir brachytherapy in 17 patients. Seven patients received only one course of EBRT (mean dose 49.5 Gy), and 2 patients were treated with interstitial (192)Ir brachytherapy alone (55 Gy and 60 Gy). Concomitant chemotherapy (5-fluorouracil and either mitomycin C or cisplatin) was delivered to 19 patients. The mean follow-up was 103 months (median 84)., Results: At the end of RT, the local tumor clinical complete response rate was 96% for T1, 87% for T2, 79% for T3, and 44% for T4. Of the 61 locally progressive tumors, 27 (44%) were salvaged with abdominoperineal resection. The rate of local tumor relapse was 12%. Among 37 local tumor relapses, 20 (54%) were salvaged with abdominoperineal resection and one with interstitial (192)Ir brachytherapy. The overall local control rate (with or without salvage local therapy) was 84%. The local control rate with good anal function (score 0 or 1) was 56.5%. Of 181 available patients with their anus preserved, 94% had good anal function. For a subgroup of 15 patients with a tumor length of <2 cm and without nodal involvement, the clinical complete response rate after RT completion was 100%, the local control rate with or without local salvage treatment was 100%, and among 13 available patients with their anus preserved, the anal function score was good in 12 patients (92%). The 10-year disease-free survival rate was 74%. After multivariate analysis, three independent predictive factors significantly influenced disease-free survival: the interval between the two courses of RT (>38 days vs. < or =38 days, p = 0.0025), pretreatment anal function score (0 vs. 1 vs. 2 vs. 3 vs. 4, p = 4.4.10(-6)), and clinical complete response after RT completion (no complete response vs. complete response, p = 2.5.10(-14))., Conclusion: We confirm the excellent results with RT in T1 and T2 lesions. However, to improve survival without colostomy with good anal sphincter function, chemoradiotherapy should be preferred for tumors > or =2 cm in length and for locally advanced tumors.

Purpose: To evaluate repeat radiosurgery (RS2) for cerebral arteriovenous malformations (AVMs) after failure of initial radiosurgery (RS1)., Methods and Materials: Between 1986 and 2000, 41 patients underwent RS2. Nine patients were not assessable: seven had insufficient follow-up (RS2 in 1999 and 2000) and two had no recent control angiography data. Thus, 32 (78%) of 41 patients were assessed. Most lesions (29 [90%] of 32) were supratentorial: 22 (69%) on the left, 8 (25%) on the right, and 2 on the midline (6%). The patients had Spetzler-Martin Grade 1-5 (median Grade 3). The symptoms before RS1 included hemorrhage in 20 (63%), epilepsy in 10 (31%), progressive neurologic deficits in 2 (6%), and headaches in 6 (19%). Five patients had two or more symptoms. Twenty-two patients (69%) had received other treatment before RS1, including neurosurgery in 3 patients (9%) and one to six embolizations in 19 patients. At RS1, the median largest nidus dimension was 2.7 cm (range 0.8-5). The median volume was 2.7 cm(3) (range 1.2-9.9). The median time from RS1 to RS2 was 52 months (range 12-126). Between RS1 and RS2, 7 (22%) of 32 patients experienced bleeding. The same irradiation technique was used for RS1 and RS2, except for 2 patients who underwent RS2 at another institution. Circular 15-MV X-ray minibeams (range 6-20 mm) and coronal arcs were used. RS1 was monoisocentric in 75% of cases and multiisocentric in 25%. At RS2, the median largest nidus dimension was 3 cm (range 1.4-5). The median volume was 4.2 cm(3) (range 0.8-13.4). RS2 was monocentric in 72% of cases and multiisocentric in 28%. After RS2, the median follow-up was 19.5 months (range 0-79; mean 25.3)., Results: After RS2, the obliteration rate was 59.3% (19 of 32). The median time to arteriographic obliteration was 21 months (range 12-96). The survival rate was 97% (31 of 32). Five of the 13 patients with a nonobliterated nidus experienced complications; 3 had bleeding (9%) and 2 without prior neurologic deficits developed partially regressive neurologic deficits. One patient with a previously existing deficit developed an additional new partially regressive neurologic deficit after an episode of bleeding. Thus, 3 (9%) of 32 patients had neurologic complications. Moderate-grade parenchymal changes at MRI increased after RS2 (88.2% vs. 57.7% after RS1; p = 0.10, not significant). However, necrosis-like changes did not significantly increase. After RS1 failure, salvage may be attempted by embolization, neurosurgery, or RS2. RS2 should be considered after the second successive annual angiogram if reduction of the nidus is <25%., Conclusion: The results after RS2 are encouraging. A multidisciplinary approach is mandatory to reduce the initial failure rate and to choose the modality and timing of salvage treatment.

Purpose: To evaluate our data concerning prognostic factors and treatment toxicity in a series of operable cervical carcinomas., Methods and Materials: Between May 1972 and January 1994, 414 patients with cervical carcinoma, staged according to the 1995 FIGO staging system (286 Stage IB1, 38 Stage IB2, 56 Stage IIA, and 34 Stage IIB with 1/3 proximal parametrial involvement), underwent radical hysterectomy with (n = 380) or without (n = 34) bilateral pelvic lymph node dissection (N+: n = 68). Group I included 168 patients who received postoperative radiation therapy (RT): 64 patients had low-dose-rate vaginal brachytherapy with a median total dose (MTD) of 50 Gy; 93 patients had external beam pelvic RT (EBPRT) with an MTD of 45 Gy over 5 weeks, followed by low-dose-rate vaginal brachytherapy (MTD: 20 Gy); and 11 patients had EBPRT alone (MTD: 50 Gy over 6 weeks). Group II included 246 patients treated with preoperative low-dose-rate uterovaginal brachytherapy (MTD: 65 Gy); 32 of these 246 patients also received postoperative EBPRT (MTD: 45 Gy over 5 weeks) delivered to the parametria and pelvic nodes. Mean follow-up from the beginning of treatment was 106 months., Results: First events included isolated locoregional recurrences (35 patients), isolated distant metastases (27 patients), and locoregional recurrences with synchronous metastases (13 patients). The 10-year disease-free survival (DFS) rate was 88% for Stage IB1, 44% for Stage IB2, 65% for Stage IIA, and 48% for Stage IIB. Multivariate analysis showed that independent factors influencing the probability of DFS were as follows: cervical site (exocervical or endocervical vs. both endo- and exocervical, relative risk [RR]: 1.77, p = 0.047), vascular space invasion (no vs. yes, RR: 1.95, p = 0.041), age (>51 years vs. 1 cm: 83% vs. 41%, respectively, p = 0.001). The overall postoperative complication rate was 10% in Group I and 9% in Group II (p = 0.7). The rate of postoperative ureteral complications requiring surgical intervention was lower in Group I than in Group II (0.6% vs. 2.3%, respectively, p = 0.03). The overall 10-year rate for Grade 3 and 4 late radiation complications was 10.4%. Postoperative EBPRT significantly increased the 10-year rate for Grade 3 and 4 late radiation complications (yes vs. no: 22% vs. 7%, respectively, p = 0.0002)., Conclusion: The prognosis for patients with cervical carcinoma was not influenced by the sequence of adjuvant RT (preoperative uterovaginal brachytherapy vs. postoperative RT) for Stages IB, IIA, and IIB with 1/3 proximal parametrial involvement. However, postoperative EBPRT increased the risk of late radiation complications.

Purpose: To identify prognostic factors and treatment toxicity in a series of operable endometrial adenocarcinomas., Methods and Materials: Between November 1971 and October 1992, 437 patients (pts) with endometrial carcinoma, staged according to the 1988 FIGO staging system (225 Stage IB, 107 Stage IC, 4 Stage IIA, 35 Stage IIB, 30 Stage IIIA, 6 Stage IIIB, and 30 Stage IIIC), underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy without (n = 140) or with (n = 297) pelvic lymph node dissection. The chronology of adjuvant RT was not randomized and depended on the usual practices of the surgical teams. Seventy-nine pts (Group I) received preoperative low-dose-rate uterovaginal brachytherapy (mean dose [MD]: 57 Gy). Three hundred fifty-eight pts (Group II) received postoperative RT. One hundred ninety-six pts received low-dose-rate vaginal brachytherapy alone (MD: 50 Gy). One hundred fifty-eight pts had external beam pelvic RT (MD: 46 Gy) followed by low-dose-rate vaginal brachytherapy (MD: 17 Gy). Four pts had external beam pelvic RT alone (MD: 47 Gy). The mean follow-up from the beginning of treatment was 128 months., Results: The 10-year disease-free survival rate was 86%. From 57 recurrences, only 12 were isolated locoregional recurrences. The independent factors decreasing the probability of disease-free survival were as follows: histologic type (clear-cell carcinoma, p = 0.038), largest histologic tumor diameter >3 cm (p = 0.015), histologic grade (p = 0.008), myometrial invasion > 1/2 (p = 0.005), and 1988 FIGO staging system (p = 9.10(-8)). In Group II, the addition of external beam pelvic RT did not seem to independently improve vaginal or pelvic control. The postoperative complication rate was 7%. The independent factors increasing the risk of postoperative complications were stage FIGO (p = 0.02) and pelvic lymph node dissection (p = 0.011). The 10-year rate for Grade 3 and 4 late radiation complications according to the LENT-SOMA scoring system was 3.1%. External beam pelvic RT independently increased the rate for Grade 3 and 4 late complication (RR: 5.6, p = 0.0096)., Conclusion: Postoperative external beam pelvic RT increases the risk of late radiation complications. After surgical and histopathologic staging with pelvic lymph node dissection, in subgroup of "intermediate-risk" patients (Stage IA Grade 3, IB-C and II), postoperative vaginal brachytherapy alone is probably sufficient to obtain a good therapeutic index. Results for patients with Stage III tumor are not satisfactory.

Purpose: To validate a computed tomography (CT) and (18)F-deoxyglucose (FDG) image fusion procedure and to evaluate its usefulness to facilitate target definition and treatment planning in three-dimensional conformal radiation therapy (3D-CRT) for non-small-cell lung cancer., Methods and Materials: Twelve patients were assessed by CT and FDG-coincidence mode dual-head gamma camera (CDET) before radiotherapy. The patients were placed in a similar position during CT and FDG-CDET. Matching was achieved by minimizing the cost function by 3D translation and rotation between four landmarks drawn on the patient's skin. Virtual simulation was performed from image fusion and estimated dose-volume histograms (DVH) were calculated., Results: Quantitative analysis indicated that the matching error was < 5 mm. Fusion of anatomic and metabolic data corrected staging of lymph nodes (N) for 4 patients and staging of metastases for 1 patient. In these 5 patients, DVH revealed that the lung volume irradiated at 20 Gy (Vl(20)) was decreased by an average of 22.8%, and tumor volume irradiated at the 95% isodose (V(95)) was increased by 22% and 8% for 2 patients, respectively, and was decreased by an average of 59% for 3 patients after fusion. No difference in terms of Vl(20) and V(95) was observed for the other 7 patients., Conclusion: We have validated CT and FDG-CDET lung image fusion to facilitate determination of lung cancer volumes, which improved the accuracy of 3D-CRT.