• Radiation Oncology Journal
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• v.9 no.1
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• pp.93-102
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• 1991

To evaluate the role of postoperative pelvic radiation therapy in rectal cancer, a retrospective analysis was done on 189 patients with modified Astler-Coiler stages B2+3, Cl , and C2+3 who were treated from February 1979 to June 1980. Forty-seven patients were staged as B2+3,17 as Cl, and 125 as C2+3. As a curative resection,41 received low anterior resection,143 received abdomino-perineal resection, and five received pelvic exenteration. The survival and disease-free survival rates of the total patients at five year were $45.3\%\;and\;44.1\%$, respectively. The stage was an important prognostic factor for survival and disease-free survival: the survival rates at five year were $63.4\%$ in stage B2+3, $62.4\%$ in C1, and $37.2\%$ in C2+3 (p<0.005): the disease-free survival rates at five year were $55.7\%$ in B2+3, $65.7\%$ in C1, and $30.4\%$ in C2+3, respectively (p<0.01). The liver was the most frequently involved organ of recurrence followed by the lung and the perineum. The patients who received low anterior resection achieved better disease-free survival but were more prone to late radiation bowel morbidities than those who received abdominoperineal resection. Postperative Pelvic radiation therapy Proved to be effective in locoregional disease control but did not prevent the appearance of distant metastasis, which was of major concern in advanced stages. Patterns of treatment failure, and factros relating to radiation morbidity are discussed, and therapeutic options for better results are proposed.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.222-228
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• 2008

Purpose: Various treatment techniques have been attempted for the radiotherapy of anal cancer because of acute side effects such as perineal skin reactions. This study was performed to investigate an optimal radiotherapy technique in anal cancer. Materials and Methods: The study subjects included 35 patients who underwent definitive concurrent chemoradiotherapy for anal cancer in Yonsei Cancer Center between 1990 and 2007. The patients' clinical data, including irradiation technique, were reviewed retrospectively. The primary lesion, regional lymph nodes, and both inguinal lymph nodes were irradiated by $41.4{\sim}45\;Gy$ with a conventional schedule, followed by a boost does to the primary lesion or metastatic lymph nodes. The radiotherapy technique was classified into four categories according to the irradiation field and number of portals. In turn, acute skin reactions associated with the treatment interruption period were investigated according to each of the four techniques. Results: 28 patients (80.0%) had grade 2 radiation dermatitis or greater, whereas 10 patients (28.6%) had grade 3 radiation dermatitis or greater during radiotherapy. Radiation dermatitis and the treatment interruption period were relatively lower in patients belonging to the posterior-right-left 3 x-ray field with inguinal electron boost and in patients belonging to electron thunderbird techniques. The interruption periods were $8.2{\pm}10.2$ and $5.7{\pm}7.7$ for the two technique groups, respectively. Twenty-seven patients (77.1%) went into complete remission at 1 month after radiotherapy and the overall 5 year survival rates were 67.7%. Conclusion: Field size and beam arrangement can affect patients' compliance in anal cancer radiotherapy, whereas a small x-ray field for the perineum seems to be helpful by decreasing severe radiation dermatitis.

• Radiation Oncology Journal
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• v.18 no.3
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• pp.194-199
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• 2000

Purpose : Then determining the lower margin of post-operative pelvic radiation therapy field according to the traditional method (recommended by Gunderson), the organs located in the low pelvic cavity and the perineum are vulnerable to unnecessary radiation. This study evaluated the effect of individualized determination of the lower margin at 2 cm to 3 cm below the anastomotic site on the failure patterns. Materials and Methods . Authors included ぉ patients with modified Astler-Coiler (MAC) stages from B2 through C3, who received low anterior resection and post-operative pelvic radiation therapy from Sept. 1994 to May 1998 at Samsung Medical Center, Sungkyunkwan University. The numbers of male and female patients were 44 and 44, and the median age was 57 years (range: 32-81 years). Three field technique (posterior-anterior and bilateral portals) by 6, 10, 15 MV X-rays was used to deliver 4,500 cGy to the whole pelvis followed by Sn cGy's small field boost to the tumor bed over 5.5 weeks. Sixteen patients received radiation therapy by traditional field margin determination, and the lower margin was set either at the low margin of the obturator foramen or at 2 cm to 3 cm below the anastomotic site, whichever is lower. In 72 patients, the lower margin was set at 2 cm to 3 cm below the anastomotic site, irrespectively of the obturator foramen, by which the reduction of radiation volume was possible in 55 patients ($76\%$). Authors evaluated and compared survival, local control, and disease-free survival rates of these two groups. Results : The median follow-up period was 27 months (range : 7-58 months). MAC stages B2 in 32($36\%$), B3 in 2 ($2\%$), Cl in 2 ($2\%$), C2 in 50 ($57\%$), and C3 in 2 ($2\%$) Patients, respectively. The entire patients' overall survival rates at 2 and 4 years were $94\%$ and $68\%$, respectively, and disease-free survival rates at 2 and 4 years were $86\%$ and $58\%$, respectively. The first failure sites were local only in 4, distant only in 14, and combined local and distant in 1 patient, respectively. There was no significant difference with respect to local control and disease-free survival rates ( p=0.42, p=0.68) between two groups of different lower margin determination policies. Conclusion : The new concept in the individualized determination of the lower margin depending on the anastomotic site has led to the equivalent local control and disease-free survival rates, and is expected to contribute to the reduction of unnecessary radiation-related morbidity by reduction of radiation volume, compared with the traditional method of lower margin determination.