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Objective To compare the efficacy after conventional radiotherapy and late course accelerated fractionation radiotherapy for nasopharyngeal carcinoma (NPC).Methods A total of 200 NPC patients were enrolled and randomly assigned to conventional radiotherapy (CF) group with 99 cases or late course accelerated fractionation radiotherapy (LCAF) group with 101 cases,who received irradiation to 60Co γ or 6 MV X-rays.In the CF group,the total dose of nasopharynx was 70 Gy/35 fractions at 2 Gy daily.In the LCAF group,for the first two-thirds of the treatment,two daily fractions of 1.2 Gy were given to the primary lesion and the total dose was 48 Gy/40 fractions.For the last one third of the treatment,the dose per fraction was increased to 1.5 Gy and the total dose was 30 Gy/20 fractions.Results There were 25,16,25 in CF group and 16,13,18 patients in LCAF group who had recurrence of nasophaynx,cervical lymph nodes,and distant metastasis,respectively.The 5-year nasopharyngeal control and overall survival rates was 75.9％ and 87.6％ in CFgroup (x2 =4.066,P＜0.05),58.0％ and 74.1％(x2 =5.076,P ＜ 0.05) in LCAF group,respectively.Cervical lymph nodes local rates and distant metastasesfree rates at 5 years were 8 1.5％ and 90.0％ in CF group (P ＞ 0.05),74.1％ and 83.3％ (P ＞ 0.05) in LCAF group,respectively.Conclusions Compared with CF,LCAF can improve nasopharyngeal control and overall survival rates,but there are no significant difference in the recurrence rates of cervical lymph nodes and distant metastasis.
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Objective To evaluate the volume of left ventricle (LV) based on PET-CT in left-sided breast cancer patients treated with adjuvant radiotherapy. To assess the impact of dose and volume in interrelations for heart and cardiac sub-structures using dose-volume histograms. Methods From October 2008 to February 2009, 14 patients with post-operatively confirmed left-sided breast cancer were enrolled in this study. Patients were scanned using contrast enhanced CT for simulation and FDG PET-CT have been applied to display the structure of left ventricle in each patient before radiotherapy (RT). The LV has been delineated based on PET-CT. Other critical sub-structures, such as left anterior descending coronary artery (LAD) have been contoured in each patient. The six-field simple intensity modulated radiotherapy (slMRT)technique has been created in all patients. Results The mean volumes of left ventricle based on PET-CT (LV-PET) were 112. 931 cm3. The volume of LV receiving ≥50% prescription dose highly correlated with the volume of heart receiving ≥50% prescription dose (R = 0. 869, P = 0. 000). There was less correlation between the volume of LAD and the volume of heart receiving ≥ 50% prescription dose ( R = 0. 220, P =0. 440). Conclusions The left ventricle could be delineated efficiently based on imaging of PET-CT. The volume of LV receiving higher dose in RT has high correlation with the volume of heart using sIMRT technique. It may pave the way for further exploring radiation induced cardiac injury in patients with breast cancer.
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Objective To determine the change of tumor bed volume during whole breast irradiation by repeated computed tomography scanning and to analyze the dosimetric impact of boost-planning on different CT images. Methods From July 2008 to Jan 2009, sixteen patients with early-stage breast cancer underwent breast conservative surgery (BCS) were enrolled in the study. All patients received whole breast irradiation and tumor bed boost, no adjuvant chemotherapy was given. Two additional CT scans were acquired in addition to the planning CT ( CT1 ), one in the course of radiotherapy ( CT2 ) and the other before the boost (CT3). Tumor beds were contoured in all CT images. Three-dimensional conformal radiotherapy planning for tumor bed boost was done on CT1 and CT3 respectively. Results The mean tumor bed volume on CT1, CT2 and CT3 were 49.5 cm3, 25.6 cm3 and 22. 2 cm3 ( F = 5. 63, P = 0. 007 ),respectively. Further analysis found statistically significant difference between CT1 and CT2 ( q = 0. 03, P =0. 010), CT1 and CT3 ( q = 0. 01, P = 0. 004), but not between CT2 and CT3 ( q = 1.00, P = 0. 333 ). The average reduction of tumor bed volume from CT1 to CT3 was 43.4%. A reduction of 20% or above was found in 88% of the patients ( n = 14), 50% or above in 38% of the patients (n = 6). In the boost-planning, the volume of the ipsilateral breast receiving 100% prescribed dose (V100%) on CT1 and CT3 was 183.5 cm3 and 144. 5 cm3, respectively ( t = 3.06, P = 0. 008 ). Conclusions Volume of tumor bed is dynamically reduced in the course of whole breast irradiation after BCS, with more important reduction in the early weeks after the beginning of irradiation. A second CT scan before tumor bed boost is warranted.
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Purpose:To investigate the prognostic factors f or local-regional control and survival in patients with regional lymph nodes re currence following mastectomy. Methods:Seventy-seven patients with their first recurrences in the regional lymph nodes treated during 1994-2003 were retrospectively analyze d. The recurrence were confined to supraclavicular region in 45 patients, in axi llary nodes in 16 patients, in internal mammary nodes in 6 patients, and with mo re than one lymph node region involved in 10 patients. The median follow-up was 34.4months. All patients were treated with radiotherapy to a total dose ranged from 50-74 Gy with a median dose of 60 Gy. Results:The median survival time was 4.67 years with 2-,5-an d 8- year survival rate of 77.8%,47.4% and 31.5% respectively. Disease-free i nterval, hormonal-receptor status were independent prognostic factors for survi val. Thirty patients had a second recurrence either in the original recurrent si te (4 patients) or in the other local-regional sites (26 patients). Chest-wall was the most frequently involved site for second recurrence, with 18 patients h ad a second recurrence including chest-wall, representing 23% of the whole coho rt. The axillary lymph nodes metastatic status of primary surgery was the only i ndependent prognostic factor for local control. Conclusions:Radiotherapy provides an efficient treatment for re gional lymph nodes recurrence following mastectomy. Twenty-three percent of pat ients present a second recurrence involving chest-wall, which suggests the sign ificance of an elective radiation to the chest-wall, especially in patients wit h 4 or more lymph nodes involved in primary surgery. Sub-group with a disease- free interval of more than 2 years, receptor positive has a better survival. The role of systemic treatment in the regional lymph nodes recurrent patients has n ot been established.
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Objective On basis of physical dose optimization, LQ model was used to investigate the difference between the curves of biological effective dose and physical isodose. The influence of applying the biological dose concept on three dimensional conformal radiotherapy of prostate carcinoma was discussed. Methods Four treatment plannings were designed for physical dose optimization: three fields, four-box fields, five fields and six fields. Target dose uniformity and protection of the critical tissue -rectum were used as the principal standard for designing the treatment planning. Biological effective dose (BED) was calculated by LQ model. The difference between the BED curve drawn in the central layer and the physical isodose curve was studied. The difference between the adjusted physical dose (APD) and the physical dose was also studied. Results Five field planning was the best in target dose uniformity and protection of the critical tissue -rectum. The physical dose was uniform in the target, but the biological effective doses revealed great discrepancy in the biological model. Adjusted physical dose distribution also displayed larger discrepancy than the physical dose unadjusted. Conclusions Intensified Modulated Radiotherapy (IMRT) technique with inversion planning using biological dose concept may be much more advantageous to reach a high tumor control probability and low normal tissue complication probability.
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Objective To evaluate the outcome , side effects and prognosis of prostate carcinoma treated with external radiotherapy. Methods From 1990 to 1999, a total of 45 prostate carcinoma patients were treated. Four cases were lost during follow up. Forty one patients underwent orchiectomy before radiation therapy , 29 received orchiectomy combined with hormone treatment. All patients received conventional radiation therapy with a median dose of 68.3 ?Gy (50.4 75.9?Gy), 1.8 2.0?Gy per fraction, five fractions weekly. Results The median follow up duration was 28 months (1 111 months). The overall 5 year survival was 76.4% and the 5 year disease specific survival was 76.5%. In terms of acute GI side effects, the frequencies of Grade Ⅰ, Ⅱ or Ⅲ reactions were 53.5%, 7.0% and 9.3% while Grade Ⅰ or Ⅱ , acute GU side effects were 41.9% and 4.7%, respectively. For the long term deleterious effects,Grade Ⅰ or Ⅱ in GI late complications were 16.7% and 7.1% and the GU late morbidities of Grade Ⅰ,Ⅱ or Ⅲ were 23.8%, 4.8% and 2.4%, respectively. Regional lymph node metastasis was closely correlated with both overall survival (P= 0.002 ) and disease specific survival (P= 0.002 ). Multivariate analysis revealed, only regional lymph node metastasis was of prognostic value to predict the overall survival and disease specific survival. Conclusion The outcome of radiation therapy for patients with T 2 T 4 prostate carcinoma is satisfactory with the side effects tolerable to most patients.