ABSTRACT
Objective To compare the therapeutic effects,toxic side effects of late-course three dimensional conformal radiotherapy plus chrono-chemotherapy(DDP+5-FU/CF) and conventional radiotherapy plus chemotherapy for nasopharyngeal carcinoma (NPC). Methods Eighty-six NPC patients admitted from Feb. 2001 to Jan. 2002 were divided randomly into two groups:1.Chrono-chemotherapy + late course three dimensional conformal radiotherapy(CCR) group—44 patients were treated by late course three dimensional conformal radiotherapy plus chrono-chemotherapy, and 2.Routine-chemotherapy-radiotherapy (RCR) group—42 patients were treated by routine chemotherapy plus radiotherapy. The patients in CCR and RCR group were comparable in age, KPS, stage and pathology. All patients were treated by combined chemotherapy and radiotherapy, with chemotherapy stared 2 weeks ahead of radiotherapy. Chemotherapy: Braun pump was used in all drug infusions;1.CCR group—DDP 80?mg/m2 starting from 10:00 until 22:00,5-Fu 750?mg/d/m2 starting from 22:00 until 10:00 next day, CF 200?mg/d/m2 starting from 10:00 every day, infused at normal speed. These drugs were given for 3 days, 14 days as one cycle, totally 2 cycle, and 2.RCR group—with the same drugs at the same total dose, only with the difference being DDP and CF given QD, starting from 10:00 but at the normal speed. 5-Fu was given throughout the day and continuously for 3 days, totally for 2 cycles. Radiotherapy: linear accelerator irradiation was given to either group. Composite facio-cervical field + anterior cervical tangential field to D_T 40?Gy/4w, followed by the coned down per-auricular field plus anterior tangential field or ?beam irradiation. In CCR group, after D_T 40gy/4w, late course 3-dimensional conformal radiotherapy(3DCRT) was used to add D_T 30?Gy/3w. In RCR group, routine radiotherapy of 40?Gy/w was supplemented with 30?Gy/3w. The total dose in either group was 70?Gy/7w at the nasopharynx, D_T60-70?Gy/6-7w at the neck, as cure while 50?Gy/5w for prophylaxis. Results The CR and PR of the CCR group was 45.5% and 95.5%, while the CR and PR of RCR group was 23.8% and 71.4% respectively. There was significant difference between the two groups in CR and PR (P
ABSTRACT
Objective To analyze the local control rate and the desimetric patterns of local recurrence in nasopharyngeal carcinoma(NPC)patients having been treated with standardized conventional radiotherapy and to evaluate the delineation of rational target volume.Methods From Jan.2000 to Dec.2000,476 patients with untreated NPC were treated by standardized conventional radiotherapy alone at the Sun Yat-sen University Cancer Center.The radiation ports were designed on a X-ray simulator.The nasopharyngeal lesion demonstrated by CT scan and the subclinical spread regions adjacent to the nasopharynx were defined as the target volume.Kaplan- Meier method was used to calculate the cumulative local recurrence rate.For patients with locad recurrence,the primary and recurrent local tumor volumes(V_(nx),V_(recur))were delineated with three-dimensional treatment planning system(3DTPS),and the dataset of radiation ports and delivered prescription dose to the 3DTPS were transferred according to the first treatment.The dose of radiation received by V_(recur)was calculated and analyzed with dose- volume histogram(DVH).Local recurrence was classified as:1.“in-port”with 95% or mere of the recurrence volume((recur)_V_(95))was within the 95% isedase;2.“marginal”with 20% to95% of _(recur)V_(95)within the 95% isedese; 3.“outside”with only less than 20% of _(recur)_V_(95)within the 95% isodose curve.Results With the median follow- up of 42.5 months(range 8～54 months),52 patients developed local recurrence.The 1-,2-,3 and 4-year cumulative local failure rate was 0.6%,3.9%,8.7% and 11.5%,respectively.Among the 42 local recurrent patients who could be analyzed by 3DTPS,52% were in-port,40% were marginal and 7% were outside.For most of the marginal recurrence and all the outside recurrence patients,the main reason of recurrence were related to the unreasonable design of the radiation port and inaccuracy in the interpretation image findings.Conclusions The outcome of better local control rate and the dosimetric pattern of local recurrence show that the target volume is reasonable for NPC in Sun Yat-sen University Cancer Center.Enhancing the capability of correct interpretation of images,accurate design of the radiation pouts and making most useful molecular or functional imaging techniques to escalate the local radiation dose are promising ways to improve the local control further and better.