• Radiation Oncology Journal
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• v.19 no.3
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• pp.265-274
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• 2001

Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.

• Radiation Oncology Journal
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• v.13 no.2
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• pp.191-198
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• 1995

Purpose: This analysis was to compare the result of radiation alone and chemoradiation in cervical cancer in terms of response, survival, failure, and complication. Materials and Methods: A retrospective analysis of 135 cervical cancer patients treated with definitive radiotherapy from November 1985 to December 1991 was performed. Fifty-six patients were treated with radiation alone and 79 patients were treated with cisplatin-based chemotherapy plus radiation. Follow-up period ranged from 5 to 105 months with a median 47 months. According to the FIGO classification, the patients were subdivided into 18 $(13.3\%)$ stage IB, 7 $(5.2\%)$ stage IIA, 97 $(71.9\%)$ stage IIB, and 9 $(6.7\%)$ stage IIIB. Results: A complete response was noted in 51 patients $(91.1\%)$ of the radiation alone group, and 68 patients $(86.1\%)$ of the chemoradiation group. There was no statistical difference in complete response rate between the two groups. Overall survival rate at 5 years was $73.3\%$. According to stage, overall survival rates at 5 years were $88.9\%$ in stage IB, $85.7\%$ in stage IIA, $73.8\%$ in stage IIB, and $37.5\%$ in stage IIIB, respectively. According to treatment modality, overall survival rates at 5 years were $81.9\%$ in the radiation alone group, $67.0\%$ in the chemoradiation group (p=0.22). Disease-free survival rate at 5 years were $70.4\%$ in the radiation alone group. $68.5\%$ in the chemoradiation group (p=0.85) Locoregional control rates at 5 years were $76.1\%$ in the radiation alone group, $73.8\%$ In the chemoradiation group (p=0.70). Distant disease-free survival rates at 5 years were $83.9\%$ in the radiation alone group, $90.3\%$ in the chemoradiation group (p=0.59). Treatment-related bone marrow suppressions were noted in 3 $(5.4\%)$ patients of the radiation alone group, 14 patients $(17.7\%)$ of the chemoradiation group (p(0.05). Grade 2 vesical complications were noted in 14 patients of the radiation alone group. and 10 Patients of the chemoradiation group. Grade 2 rectal complications were noted in 2 patients of the radiation alone group, and 3 Patients of the chemoradiation group. One case of rectal perforation was noted in the chemoradiation group, and grade 2 small bowel obstructions were noted in 2 patients of the radiation alone group. There were no statistical differences in the incidence of vesicar, rectal, and small bowel complicaions between the two groups. Conclusion: No statistical difference was found between the radiation alone group and the chemoradiation group in terms of response, survival, and failure. but the incidence of bone marrow suppression was higher in the chemoradiation group.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.477-483
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• 1998

Purpose : Radiation proctitis and radiation cystitis are frequent and problematic late complications in patients treated with radiation for the uterine cervix cancer. Authors tried to find out the better patient's position in high dose rate intracavitary radiation to reduce the radiation dose of bladder and rectum. Materials and Methods : In 13 patients, Foley Catheters were inserted to patient's bladder and rectum and were ballooned with radioopaque dye. After insertion of a tandem and two ovoids, semi-orthogonal anteroposterior and lateral films were taken in both lithotomy and supine position. The rectal point and bladder point were defined according to the criteria recommended in the ICRU Report 38 with modification. Using these films, all patients' bladder and rectal dose were calculated in both positions (the radiation dose of A point was set to 400 cGy). And also, the distance of bladder and rectum from uterine cervical os was calculated in both positions. Results : The average radiation dose of rectum was 240.7 cGy in lithotomy position and 278.3 cGy in supine position, and the average radiation dose of bladder was 303.5 cGy in lithotomy position and 255.8 cGy in supine position. After the paired t-test, the radiation dose of rectum in lithotomy position was marginally significantly lower than that in supine position, while the radiation dose of bladder in lithotomy position was significantly higher than that in supine position. On the other hand, the average distance between rectum and cervical os was 35.2 mm in lithotomy position and 32.3 mm in supine position. and the average distance between bladder and cervical os was 30.4 mm in lithotomy position and 34.0 mm in supine position. After the paired t-test. the distance between rectum and cervical os in lithotomy position was significantly longer than that in supine position, while the distance between bladder and cervical os in lithotomy position was significantly shorter than that in supine position. Conclusion : The radiation dose of bladder can be reduced in supine position and the radiation dose of rectum can be reduced in lithotomy position, so we can choose appropriate position in each patient.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.71-82
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• 2011

Purpose: To evaluate the biochemical control rate and the rate of side effects after performing permanent brachytherapy of localized prostate cancer. Materials and Methods: 67 patients with localized prostate cancer were treated with brachytherapy between April 2007 and December 2008. Of these, 43 patients who were followed up and did not receive external radiotherapy were evaluated for the change in prostate specific antigen (PSA) level and the occurrence of side effects. In total, 18 patients were classified as low risk, 19 patients as intermediate risk, and 6 patients as high risk. The prescription dose was 145 Gy. Results: A PSA increase greater than 2 ng/mL occurred in 2 patients (4.7%). Radiation Therapy Oncology Group (RTOG) grade 1 and 2 acute urologic complications (UC) occurred in 40 and 3 patients, respectively. Further, 5 patients had RTOG grade 1 acute rectal complication (RC). The numbers of RTOG grade 1, 2, and 3 chronic UC were 1, 4, and 1, respectively. The numbers of RTOG grade 1, 2, and 4 chronic RC were 5, 10, and 3, respectively. The statistically significant risk factors (RF) of acute RC were the minimal dose in the most irradiated 0.1 cc volume ($D_{0.1cc}$, p=0.041) and absolute volume receiving 150% of the prescribed dose ($V_{150cc}$, p=0.038) in the entire rectum (ER). The percentage ($V_{100%}$, p=0.019) and absolute volume ($V_{100cc}$, p=0.047) in the involved rectum (IR) were also statistically significant. The RF of chronic RC were $V_{100%}$ (p=0.011) in the ER and the $D_{0.1cc}$ (p=0.049), $V_{100cc}$ (p=0.023) in the IR. The number of used seeds were related with acute UC (p=0.028). Conclusion: Permanent brachytherpy of localized prostate cancer showed a favorable short term biochemical control rate. As such, selective intermediate and high risk patients can be managed with permanent brachytherapy. The effort to reduce rectal complication is also necessary.

• Radiation Oncology Journal
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• v.20 no.4
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• pp.343-352
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• 2002

Purpose : Radiotherapy is the main treatment modality for uterine cervix cancer. Since the rectum is in the radiation target volume, rectal bleeding is a common late side effect. This study evaluates the risk factors of radiation induced rectal bleeding and discusses its optimal management. Materials and Methods : total of 213 patients who completed external beam radiation therapy (EBRT) and intracavitary radiation (ICR) between September 1994 and December 1999 were included in this study. No patient had undergone concurrent chemo-radiotherapy. Ninety patients received radiotherapy according to a modified hyperfractionated schedule. A midline block was placed at a pelvic dose of between 30.6 Gy to 39.6 Gy. The total parametrial dose from the EBRT was 51 to 59 Gy depending on the extent of their disease. The Point A dose from the HDR brachytherapy was 28 Gy to 30 Gy $(4\;Gy\times7,\;or\;5\;Gy\times6)$. The rectal point dose was calculated either by the ICRU 38 guideline, or by anterior rectal wall point seen on radiographs, with barium contrast. Rectal bleeding was scored by the LENT/SOMA criteria. For the management of rectal bleeding, we opted for observation, sucralfate enema or coagulation based on the frequency or amount of bleeding. The median follow-up period was 39 months $(12\~86\;months)$. Results : The incidence of rectal bleeding was $12.7\%$ (27/213); graded as 1 in 9 patients, grade 2 in 16 and grade 3 in 2. The overall moderate and severe rectal complication rate was $8.5\%$. Most complications $(92.6\%)$ developed within 2 years following completion of radiotherapy (median 16 months). No patient progressed to rectal fistula or obstruction during the follow-up period. In the univariate analysis, three factors correlated with a high incidence of bleeding an icruCRBED greater than 100 Gy $(19.7\%\;vs.\;4.2\%)$, an EBRT dose to the parametrium over 55 Gy $(22.1\%\;vs.\;5.1\%)$ and higher stages of III and IV $(31.8\%\;vs.\;10.5\%)$. In the multivariate analysis, the icruCRBED was the only significant factor (p>0.0432). The total parametrial dose from the EBRT had borderline significance (p=0.0546). Grade 1 bleeding was controlled without further management (3 patients), or with sucralfate enema 1 to 2 months after treatment. For grade 2 bleeding, sucralfate enema for 1 to 2 months reduced the frequency or amount of bleeding but for residual bleeding, additional coagulation was peformed, where immediate cessation of bleeding was achieved (symptom duration of 3 to 10 months). Grade 3 bleeding lasted for 1 year even with multiple transfusions and coagulations. Conclusion : Moderate and several rectal bleeding occurred in $8.5\%$ of patients, which is comparable with other reports. The most significant risk factor for rectal bleeding was the accumulated dose to the rectum (icruCRBED), which corrected with consideration to biological equivalence. Prompt management of rectal bleeding, with a combination of sucralfate enema and coagulation, reduced the duration of the symptom, and minimized the anxiety/discomfort of patients.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.255-262
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• 1997

Purpose : This is retrospective study to compare the results of radiation therapy alone and neoadjuvant chemotherapy and radiation in advanced stage of uterine cervical cancer. Materials and Methods : Seventy-six Patients who were treated with definitive radiation therapy for locally advanced cervical cacinoma between June 1988 and December 1993 at the department of radiation oncology, Keimyung University Dong-san Hospital. Thirty six patients were treated with radiation therapy alone and forty patients were treated with cisplatin based neoadjuvant chemotherapy and radiation therapy. According to FIGO staging system. there were 48 patients in stage IIb, 3 patients in stage IIIa, 23 patients in stage lIIb and two patients in stage IVa with median age of 53 years old. Follow-up periods ranged from 7 to 95 months with median 58 months. Results : Complete response (CR) rate were $86.1\%$ in radiation alone group and $80\%$ in chemoradiation group. There was no statistical difference in CR rate between the two groups. Overall five-year survival rate was $67.3\%$. According to stage, overall five-rear survival rates were $74\%$ in stage IIb, $66.7\%$ in stage IIIa, $49.8\%$ in stage IIb, $50\%$ in stage IVa. According to treatment modality overall five year survival rates were $74.1\%$ in radiation alone and $61.4\%$ in chemoradiation group (P=0.4) Five rear local failure free survival rates were $71.5\%$ in radiation alone group and $60\%$ in chemoradiation group (P=0.17). Five year distant metastasis free survival rates were $80.7\%$ in radiation aione group and $89.9\%$ in chemoradiation group (P=0.42). Bone marrow suppression (more than noted in 3 cases of radiaion alone group and 1 case of chemoradiation group. Grade II retal complication was noted in 5 patients of radiation group and 4 patients In chemoradiation group. Bowel obstruction treated with conservative treatment (1 patient) and bowel perforation treated with surgery (1 patient) were noted in radiation alone group. There was no statistical difference in complication between two groups. Conclusion : There was no statistical difference in survival, failure and complication between neoadjuvant chemotherapy and radiation versus radiation alone in locally advanced uterine cervical carcinoma.

• Radiation Oncology Journal
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• v.6 no.1
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• pp.55-61
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• 1988

Fifty patients with residual, unresectable or recurrent rectal cancer were treated with external irradiation using a 6-MV linear accelerator at the Division of Therapeutic Radiology, Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College during the period of April 1983 to December 1987. This paper describes the results of a retrospective analysis of the results of external irradiation for the residual, unresectable and recurrent rectal cancer in 46 patients. Four patients were lost to follow-up. Of the 46 patients, $18 (39\%)$ presented with unresectable primary lesions and $28 (61\%)$ with residual or recurrent rectal cancer. In $93\%$, the pathologic diagnosis was adenocarcinoma. Resonse to irradiation was observed in $22 (73\%)$ out of 30 patients who were treated for pain, $12 (86\%)$ out of 14 patients who were treated for mass, and $17 (77\%)$ out of 22 patients who were treated for bloody discharge. The actuarial postoperative 2-year and 3-year survival rates in recurrent and unresectable patients were $43\%$ and $22\%$, respectively. However, the post-RT 2-year survival rate was $13\% (6/46)$.

• Radiation Oncology Journal
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• v.14 no.3
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• pp.191-199
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• 1996

Purpose : To evaluate 5-year survival rate, patterns of failure and complications of cervical cancer treatment, fifty nine patients treated by curative radiotherapy for the uterine cervical cancer were analyzed retrospectively. Materials and Methods : From March 1986 to May 1990, fifty nine patients with histologically proven uterine cervical cancer were analyzed. According to FIGO stage, there were 2 patients ($3.4\%$) in stage Ib, 2 patients ($3.4\%$) in stage IIa, 31 patients ($52.5\%$) in stage IIb, 15 patients ($25.4\%$) in stage IIIb, 9 patients ($15.3\%$) in stage IV. External RT was per formed by 6 MVLINAC with daily 1.8 Gy, 5 times per week and followed by ICR. A point dose of ICR was calculated to 30-43.66 Gy (median: 34.6 Gy). These techniques delivered total A Point dose of 80.4 to 109.8 Gy (median: 85 Gy). Patients had been followed up from 2 to 110 months (median: 61 months) Results : The overall 5-year survival rate & disease free survival rate were $55.9\%$ and $55.0\%$ respectively. According to FIGO stage, the 5-year survival rate for less than IIa, IIb, IIIb, IV were $75.0\%$, $74.8\%$, $26.7\%$, $33.3\%$, respectively. In univariate analysis, the 5-year survival rate for stage IIb and below versus stage IIIa and above revealed $74.8\%$, $29.2\%$ respectively (P<0.005). According to the hemoglobin level during RT, the 5-rear survival rate of was $73.3\%$ for patients with Hg 10 gm/dL or higher, in contrast to $0\%$ for those with lower than 10 gm/dL (p<0.005). In 18 patients with nonbulky tumor (<5cm), the 5-year survival rates were $71.8\%$. The 5-rear survival rates for 18 patients with 5 cm or greater in tumor diameter were $22.2\%$ (p<0.005). The 5-year survival rate for Patient age of above 50 years and below were $65.3\%$ $34.2\%$ respectively (p<0.05). ECOG performance status. pathologic finding, total dose, total treatment time were not statistically significant factors. The significant prognostic factors affecting overall 5-year survival rate by multivariate analysis showed the hemoglobin level during RT (P=0.0001), tumor size (p=0.0390), FIGO stage (p=0.0468). Total recurrence rate was $23.7\%$ local failure $15.2\%$ (9/59), distant metastasis $6.8\%$ (4/59), local and distant metastasis $1.7\%$ (1/59). According to the RTOG/EORTC Soma Scales, the late complication rate was $23.8\%$ (14/59) The late complication rate of colorectum and genitourinary tract were $15.3\%$ (9/59), $8.5\%$ (5/59), respectively: 10 patients ($17.0\%$) were grade 2, 3 Patients ($5.1\%$) were grade 3 and one patient ($1.7\%$) was grade 4. The late complications were radiation proctitis, rectal bleeding, radiation colitis, diarrhea and radiation cystitis in decreasing order. Conclusion : For improvement of therapeutic results, prospective randomized trials are recomended to discover new prognostic factors and more aggressive radiation therapeutic methods are needed for poor prognostic patients. The adjuvant chemotherapy or radiation-sensitizing agents must be considered to inhibit regional and distant metastasis.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.133-140
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• 2010

Purpose: We retrospectively investigated the effect of irradiation using helical tomotherapy in recurrent pelvic tumors that underwent prior irradiation. Materials and Methods: Fourteen patients with recurrent pelvic tumors consisting of rectal cancer (57.1%), cervical cancer (35.7%) and cancer with an unknown origin (7.1%) were treated with tomotherapy. At the time of irradiation, median tumor size was 3.5 cm and 7 patients complained of pain originating from a recurrent tumor. The median radiation dose delivered to the gross tumor volume, clinical target volume, and planning target volume was 50 Gy, 47.8 Gy and 45 Gy, respectively and delivered at 5 fractions per week over the course of 4 to 5 weeks. Treatment response and duration of local disease control were evaluated using the Response Evaluation Criteria in Solid Tumors (ver. 1.0) and the Kaplan-Meyer method. Treatment-related toxicities were assessed through Common Terminology Criteria for Adverse Events (ver. 3.0). Results: The median follow-up time was 17.3 months, while the response rate was 64.3%. Symptomatic improvement appeared in 6 patients (85.7%). The median duration time of local disease control was 25.8 months. The rates of local failure, distant failure, and synchronous local and distant failure were 57.1%, 21.4%, and 7.1%, respectively. Acute toxicities were limited in grade I or II toxicities, except for one patient. No treatment related death or late toxicity was observed. Conclusion: Helical tomotherapy could be suggested as a feasible palliative option in recurrent pelvic tumors with prior radiotherapy. However, to increase treatment effect and overcome the limitation of this outcome, a large clinical study should be performed.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.199-206
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• 2003

Purpose: This study was undertaken to evaluate the efficacy of postoperative radiotherapy, and to investigate the prognostic factors for FIGO stages IB-IIB cervical cancer patients who were treated with simple hysterectomy, or who had high-risk factors following radical hysterectomy and pelvic lymph node dissection. Materials and Methods: Between March 1986 and December 1998, 58 patients, with FIGO stages IB-IIB cervical cancer were included in this study. The indications for postoperative radiation therapy were based on the pathological findings, including lymph node metastasis, positive surgical margin, parametrial extension, lymphovascular invasion, invasion of more than half the cervical stroma, uterine extension and the incidental finding of cervix cancer fellowing simple hysterectomy. All patients received external pelvic radiotherapy, and 5 patients, received an additional intracavitary radiation therapy. The radiation dose from the external beam to the whole pelvis was $40\~50$ Gy. Vagina cuff Irradiation was peformed, after completion of the external beam irradiation, at a low-dose rate of Cs-137, with the total dose of $4488\~4932$ chy (median: 4500 chy) at 5 mm depth from the vagina surface. The median follow-up period was 44 months ($15\~108$ months). Results: The 5-yr actuarial local control rate, distant free survival and disease-free survival rate were $98\%,\;95\%\;and\;94\%$, respectively. A univariate analysis of the clinical and pathological parameters revealed that the clinical stage (p=0.0145), status of vaginal resection margin (p=0.0002) and parametrial extension (p=0.0001) affected the disease-free survival. From a multivariate analysis, only a parametrial extension independently influenced the disease-free survival. Five patients ($9\%$) experienced Grade 2 late treatment-related complications, such as radiation proctitis (1 patient), cystitis (3 patients) and lymphedema of the leg (1 patient). No patient had grade 3 or 4 complications. Conclusion: Our results indicate that postoperative radiation therapy can achieve good local control and survival rates for patients with stages IB-IIB cervical cancer, treated with a simple hysterectomy, as well as for those treated with a radical hysterectomy, and with unfavorable pathological findings. The prognostic factor for disease-free survival was invasion of the parametrium. The prognosic factor identified in this study for treatment failure can be used as a selection criterion for the combined treatment of radiation and che motherapy.