• Radiation Oncology Journal
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• v.16 no.3
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• pp.311-323
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• 1998

Purpose : Prospective, single arm, Phase I/II clinical trial was performed to assess the efficacy and toxicity of the concurrent chemotherapy and definitive radiotherapy (RT) in patients with previously untreated locally advanced carcinoma of the uterine cervix. Methods and Materials : From Mar 1992 to January 1997, a total of 73 patients with advanced cervical carcinoma were entered on the protocol but 5 patients were excluded in analysis because of patients' refusal of treatment. Their ages ranged from 31 to 77 years, median 58 years. The International Federation of Gynecology and Obstetrics (FIGO) stage distribution was as follows: IIB 46, IIIA 2, IIIB 15 and IVA 5. RT consisted of external beam irradiation to 4,140-5,040 cGy/23-28 fractions plus high dose rate intracavitary treatments to deliver a dose of 30-35 Gy to point A in 6-7 fractions. During the intracavitary treatments parametrial boost was delivered for point B dose of 60 Gy in stage IIB and 65 Gy in stage IIIB. Two cycles of concurrent 5-fluorouracil and cisplatin (FP) chemotherapy (5-fluorouracil 1,000 mg/$m^2$/day continuous infusion for 4 days, day 1-4, 29-32 and cisplatin 20 mg/$m^2$/day intravenous bolus for 3 days day 1-3, 29-31) administered starting on day 1 of RT. Results : The median follow-up was 24 months (range 4-68+). Sixty-four patients were evaluable for survival rate in this protocol: The 5-year actuarial and disease-free survival rate were 52$\%$ and 64$\%$, respectively. The 5-rear actuarial survival for stage IIB and III+IVA patients were 58$\%$ and 36$\%$, respectively The 5-year disease-free survival rate for stage IIB and III+IVA patients were 71$\%$ and 40$\%$, respectively. Of the 68 patients evaluated for patterns of failure, overall recurrence rate was 27.9$\%$ (19/68) : local failure in 5.9$\%$ (4/68), distant metastasis in 10.3$\%$ (7/68) and both in 11.8$\%$ (8/68). Of the 64 patients evaluated for response at one month after the completion of treatment the complete response rate was 78$\%$ (50/64). Concurrent chemoradiation appear to be a well-tolerated regimen but there were two treatment-related deaths. Conclusion : Concurrent chemotherapy of FP with high-dose definitive RT in locally advanced carcinoma of the uterine cervix is feasible and effective with acceptable toxicities. This chemoradiation regimen may offer a modest survival benefit for advanced stage. Further follow-up of these patients will evaluate the impact of this regimen on the long-term local control and their survival.

• Progress in Medical Physics
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• v.21 no.3
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• pp.253-260
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• 2010

Most brachytherapy treatment planning systems employ a dosimetry formalism based on the AAPM TG-43 report which does not appropriately consider tissue heterogeneity. In this study we aimed to set up a simple Monte Carlo-based intracavitary high-dose-rate brachytherapy (IC-HDRB) plan verification platform, focusing particularly on the robustness of the direct Monte Carlo dose calculation using material and density information derived from CT images. CT images of slab phantoms and a uterine cervical cancer patient were used for brachytherapy plans based on the Plato (Nucletron, Netherlands) brachytherapy planning system. Monte Carlo simulations were implemented using the parameters from the Plato system and compared with the EBT film dosimetry and conventional dose computations. EGSnrc based DOSXYZnrc code was used for Monte Carlo simulations. Each $^{192}Ir$ source of the afterloader was approximately modeled as a parallel-piped shape inside the converted CT data set whose voxel size was $2{\times}2{\times}2\;mm^3$. Bracytherapy dose calculations based on the TG-43 showed good agreement with the Monte Carlo results in a homogeneous media whose density was close to water, but there were significant errors in high-density materials. For a patient case, A and B point dose differences were less than 3%, while the mean dose discrepancy was as much as 5%. Conventional dose computation methods might underdose the targets by not accounting for the effects of high-density materials. The proposed platform was shown to be feasible and to have good dose calculation accuracy. One should be careful when confirming the plan using a conventional brachytherapy dose computation method, and moreover, an independent dose verification system as developed in this study might be helpful.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.377-385
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• 1993

Five hundred and fifty patients treated for carcinoma of the uterine cervix at the Department of Therapeutic Radiology, Seoul National University Hospital from 1979 to 1986, were analyzed retrospectively for late bladder complications. Of them,468 patients received primary radiotherapy for the cervix cancer in intact uterus, and the other 82 patients were treated postoperatively. The cumulative incidence of radiation induced bladder complication of grade 2 or 3 was $2.5\%$ at five years. The mean bladder dose for the group of patients with complication was higher than that of the group without complication, and the difference was statistically significant (p<0.01). But relationship between mean bladder dose and severity of complication was not found. The frequency of complication (grade I, II, III) increased as a function of radiation dose to bladder from $5.0\%$ for patients with bladder dose less than 6,500 cGy to $27.7\%$ for patients with bladder dose higher than 8,000 cGy. Among various factors, the age of patient and the distance between ovoids turned out to have significant effect on the complication.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.223-229
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• 2005

Purpose: In this work we designed and made MPBP(Multi Purpose Brachytherapy Phantom). The MPBP enables one to reproduce the same patient set-up in MPBP as the treatment of the patient and we tried to get an exact analysis of rectal doses in the phantom without need of in-vivo dosimetry. Materials and Methods: Dose measurements were tried at a point of rectum 1, the reference point of rectum, with a diode detector for 4 patients treated with tandem and ovoid for a brachytherapy of a cervix cancer. Total 20 times of rectal dose measurements were made with 5 times a patient. The set-up variation of the diode detector was analyzed. The same patient set-ups were reproduced in self-made MPBP and then rectal doses were measured with TLD. Results: The measurement results of the diode detector showed that the set-up variation of the diode detector was the maximum $11.25{\pm}0.95mm$ in the y-direction for Patient 1 and the maximum $9.90{\pm}4.50mm,\;20.85{\pm}4.50mm,\;and\;19.15{\pm}3.33mm$ in the z-direction for Patient 2, 3, and 4, respectively. Un analyzing the degree of variation in 3 directions the more variation was showed in the z-direction than x- and y-direction except Patient 1. The results of TLD measurements in MPBP showed the relative maximum error of 8.6% and 7.7% at a point of rectum 1 for Patient 1 and 4, respectively and 1.7% and 1.2% for Patient 2 and 3, respectively. The doses measured at R1 and R2 were higher than those calculated except R point of Patient 2. this can be thought to related to the algorithm of dose calculation, whcih corrects for air and water but is guessed not to consider the correction for the scattered rays, but by considering the self-error (${\pm}5%$) TLD has the relative error of values measured and calculated was analyzed to be in a good agreement within 15%. Conclusion: The reproducibility of dose measurements under the same condition as the treatment could be achieved owing to the self-made MPMP and the dose at the point of interest could be analyzed accurately. If a treatment is peformed after achieving dose optimization using the data obtained in the phantom, dose will be able to be minimized to important organs.

• Radiation Oncology Journal
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• v.13 no.2
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• pp.181-189
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• 1995

Pupose: Radiation therapy(RT) is conventionally standard treatment for locally advanced stage for uterine cervix cancer. Recently to improve treatment results, combined chemotherapy and radiation therapy was tried We retrospectively analysed our experience of 122 patients. Comparision of the results in 45 patients treated with RT alone and 77 patients treated with RT plus chemotherapy was made Materials and Mathods: From January 1985 to December 1991 122 patients with cervix cancer were treated with whole pelvic external RT and ICR(34 1 ICR, 77 2 ICR, 11 high dose rate ICR) in our department. Forty five patients were treated with RT alone, and 77 patients were treated with combined RT plus chemotherapy Mean age was 58 years(range:29-81). Histologic types were 111 squamous cell carcinoma, 5 large cell carcinoma, 3 adenocarcinoma, and 2 adenosquamous cell carcinoma. According to the FIGO stage 6 had stage $IA(4.9\%),$ 11 had $IIA(9.0\%),$ 37 had $IIB(30.3\%),$ 3 had $IIIA(2.5\%),$ 63 had $IIIB(51.6\%).$ and 2 had stage $IV(1.6\%).$ In 77 patients with RT Plus chemotherapy, 36 patients were treated with VBP(vinblastin, bleomycin, cisplatinum) , 39 patients with cisplatinum plus 5-FU and 2 patients with 5-FU. Results: Complete response after external RT (3960cGy-5500cGy) was achieved in 61 patients$(50\%).$ The actuarial 5 year and 9 rear survival rate was $57.8\%\;and\;53.9\%,$ respectively. Five rear actuarial survival rate was $63.1\%$with RT alone(n=45) and $55.9\%$ with RT plus chemotherapy(n=77). The 5 rear survival rate was $35.5\%$ for 1 course of ICR and $67\%$ for 2 courses of ICR. There was statistically significant advantage of survival with RT alone group who were treated with 2 courses of ICR and dose to the A Point)=8000cGy (4/25 died). In RT plus chemotherapy group, dose response was not seen and there was no difference in 5 year survival between 1 course and 2 course of ICR $(50\%\;vs\;56.8\%),$ and dose to point A less than 8000 cGy and more than 8000 $cGy(55.6\%\;vs\;55.7\%).$ There was no significant difference in survival between RT alone and RT plus chemotherapy for patients with tumor size greater than 3cm in size. Five year survival rate for early stage (Stage IB and IIA) with RT alone group and with RT Plus chemotherapy group was $60\%\;and\;77.0\%,$ respectively In advanced stage (stage IIB, IIIA, IIIB, IVA) the 5 year actuarial survival rate were $62.6\%,$ for RT alone group vs $53.6\%$ for RT plus chemotherapy group. Conclusion: Present study demonstrates that there is no survival advantage with adding chemotherapy in advanced stage of uterine cervix cancer. RT alone is considered as treatment of choice for patients with locally advanced cervix cancer. There was increased survival in RT alone group treated with RT dose above 8000 cGy to point A and 2 course of ICR. but 2 course of ICR and RT dose above 8000 cGy to point A did not affect survival advantage in RT plus chemotherapy group.