ABSTRACT
Objective:To investigate the dosimetric characteristics, acute toxicity and short-term efficacy of postmastectomy hypofractionated internal mammary (IM) chain irradiation with electrons in patients with high-risk breast cancer.Methods:A total of 155 patients with breast cancer who underwent modified mastectomy between November 2018 and January 2020 were selected. Among them, 137(88.4%) patients were classified as stage Ⅲ and 18(11.6%) as stage Ⅱ. All patients received standard chemotherapy, endocrine therapy and anti-Her2 targeted therapy. CTV im was divided into three subregions: CTV im1, CTV im2 and CTV im3, which represented the first, second and third intercostal IM, respectively. The planning target volume of subraclavicular region (PTV sc) was delineated. CTV cw and CTV im were irradiated with 6-15 MeV electron at 43.5 Gy in 15 fractions over 3 weeks. Moreover, PTV sc was irradiated with 6 MV X-ray at 43.5 Gy in 15 fractions over 3 weeks using two-dimensional radiotherapy (2DRT) or three-dimensional radiotherapy (3DRT). The dosimetric characteristics of CTV im, PTV sc, lung, heart, left anterior descending coronary artery (LAD) and right coronary artery (RA) were evaluated, and the acute toxicity and short-term efficacy were analyzed. Results:The mean dose (D mean) of CTV im was (43.3±2.6) Gy, D 95% was (30.5±8.3) Gy, V 90% was (85.0±10.5)% and V 80% was (91.0±7.4)%, respectively. The corresponding parameters of CTV im1 were significantly lower than those of CTV im2 and CTV im3(all P<0.001). Body mass index exerted no significant effect on IM dose ( P>0.05). Compared with 2DRT, 3DRT for SC significantly increased theD mean of CTV im[(43.4±2.6) Gy vs.(41.4±2.3) Gy, P=0.021], and the hot spot within PTV sc[V 110%: (26.7±17.5) cm 3vs.(12.5±8.4) cm 3, P=0.018; V 120%: (6.1±5.3) cm 3vs.(2.0±2.6) cm 3, P=0.023]. TheD mean of the ipsilateral lung was (9.8±1.9) Gy, and V 20Gy was (19.7±4.7)%. TheD mean of heart was (3.3±1.7) Gy in the whole group, (4.7±1.4) Gy for the left-sided breast cancer and (2.6±1.2) Gy for the right-sided breast cancer, respectively. TheD mean of LAD for the left-sided breast cancer was (13.9±4.9) Gy. TheD mean of RA for the right-sided breast cancer was (7.5±3.7) Gy. The incidence rates of ≥ grade 2 acute radiation dermatitis, esophagitis and pneumonitis were 19.3%, 4.5% and 2.6%, respectively. With a median follow-up time of 20.5 months (range: 9.9-41.8 months), 2 cases of chest wall recurrence, 2 regional lymph node recurrence, 6 distant metastases and 1 death were reported. Conclusions:When hypofractionated internal mammary chain is irradiated by electrons after mastectomy, the doses to the lung, heart and coronary artery are low, and the acute toxicities are mild. However, the dose to CTV im1 is inadequate. Although short-term efficacy is high, long-term follow-up is warranted.
ABSTRACT
The efficacy of palliative care was definitive with two-dimensional radiotherapy for stage IV non-small cell lung cancer(NSCLC).However,theimpact of radiotherapy on survival was not well indicated,and some study resultsindicating prolonged survival were not accepted. Along with the advancesin three-dimensional radiotherapy (3DRT),wide application of comprehensive treatment,and the understanding of the association between different metastatic status and survival,prospective and retrospective studies have demonstrated that chemotherapy combined with 3DRT for primary tumor is more effective than chemoradiotherapy alone in improving symptoms and prolonging survival,especially for oligometastases of stage IV NSCLC.The dose to primary tumor is closely related to survival,and high-dose radiotherapy may be more likely to prolong survival. Further studies,however,areneeded to take into accountproblems such as thedose,timing,and technical selection of radiotherapy.
ABSTRACT
Objective To compare the prognostic value of the 7th edition of AJCC cancer staging system in nasopharyngeal carcinoma (NPC) patients treated with conventional radiotherapy (CRT) and intensity-modulated radiotherapy (IMRT).Methods From January 2004 to December 2006,totally 1138 NPC patients were treated with CRT (790 patients) and IMRT (348 patients) in Cancer Hospital of Fujian province.The median ages were 47 and 45 years old for two groups ( x2 =1.49,P =0.222 ),respectively.There were 0,41,488,261 and 5,65,176,102 patients in stage Ⅰ,Ⅱ,Ⅲ,Ⅳ of the two groups after restaged with 7th edition of AJCC cancer staging system,respectively (x2 =64.78,P =0.001 ).The 3-year survival was analyzed according to T-category,N-category and overall stage.Results The follow-up rate at 3 years is 96.0％.The median follow-up were 32 months and 33 months for CRT and IMRT groups.N-category was found to be the prognostic factors for overall survival (OS,x2 =6.50,P =0.038 and x2 =13.60,P =0.004) and metastasis free survival ( MFS,x2 =7.78,P =0.009 and x2 =15.30,P =0.002) for CRT and IMRT groups.The clinical stage was prognostic factor for OS in conventional group ( x2 =6.70,P=0.035),and for MFS in IMRT group (x2 =9.12,P=0.028).Conclusions The T-calegory of 7th AJCC staging system shows poor predictive value for the long-term survival of NPC patients.The N-calegory of 7th AJCC staging system can well estimate the OS and MFS for NPC.