• 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.

• Journal of radiological science and technology
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• v.36 no.1
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• pp.39-47
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• 2013

For radiotherapy in rectal cancer patients treated with small bowel displacement device (SBDD) and belly board, We will suggest new indication of using SBDD depending on obesity index by analyzing correlation between obesity and irradiated small bowel volume. In this study, We reviewed 29 rectal cancer patients who received pelvic radiation therapy with belly board and SBDD from January to April in 2012. We only analyzed those patients treated with three-field technique (PA and both LAT) on 45 Gy (1.8 Gy/fx). We measured patients' height, weight, body mass index (BMI), waist-hip ratio (WHR) and divided BMI into two groups.(${\geq}23$:BMI=group1, <23:BMI=group2) We performed a statistical analysis to evaluate correlation between total volume of bladder($TV_{bladder}$), obesity index and high dose volume of small bowel (small bowel volume irradiated at 90% of prescribed dose, $HDV_{sb}$), low dose volume of small bowel (small bowel volume irradiated at 33% of prescribed dose, $LDV_{sb}$). The result shows, gender, WHR and status of pre operative or post operative do not greatly affect $HDV_{sb}$ and $LDV_{sb}$. Statistical result shows, there are significant correlation between $HDV_{sb}$ and BMI (p<0.04), $HDV_{sb}$ and $TV_{bladder}$ (p<0.01), $LDV_{sb}$ and $TV_{bladder}$ (p<0.01). BMI seems to correlate with $HDV_{sb}$ but does not with $LDV_{sb}$ (p>0.05). There are negative correlation between $HDV_{sb}$ and BMI, $TV_{bladder}$ and $HDV_{sb}$, $TV_{bladder}$ and $LDV_{sb}$. Especially, BMI group1 has more effective and negative correlation with $HDV_{sb}$ (p=0.027) than in BMI group2. In the case of BMI group 1, $TV_{bladder}$ has significant negative correlation with $HDV_{sb}$ and $LDV_{sb}$ (p<0.04). In conclusions, we confirmed that Using SBDD with belly board in BMI group1 could more effectively reduce irradiated small bowel volume in radiation therapy for rectal cancer. Therefore, We suggest using belly board with SBDD in order to reduce the small bowel toxicity in rectal radiotherapy, if patients' BMI is above 23.

• Radiation Oncology Journal
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• v.24 no.3
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• pp.171-178
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• 2006

[ $\underline{Purpose}$ ]: To determine the efficacy and safety of concurrent chemotherapy and radiation therapy with high-dose-rate brachytherapy for cervical cancer. $\underline{Materials\;and\;Methods}$: From January 2001 to December 2002, 30 patients with cervical cancer were treated with concurrent chemotherapy (cisplatin and 5-FU) and definitive radiation therapy. The median age was 58 (range $34{\sim}74$) year old. The pathology of the biopsy sections was squamous cell carcinoma in 29 patients and one was adenocarcinoma. The distribution to FIGO staging system was as follows: stage IB, 7 (23%); IIA, 3 (10%); IIB, 12 (40%); IIIA, 3 (10%); IIIB, 5 (17%). All patients received pelvic external beam irradiation (EBRT) to a total dose of $45{\sim}50.4\;Gy$ (median: 50.4 Gy) over $5{\sim}5.5$ weeks. Ir-192 HDR intracavitary brachytherapy (ICBT) was given after a total dose of 41.4 Gy. HDR-ICBT was performed twice a week, with a fraction point A dose of 4 Gy and median dose to point A was 28 Gy (range: $16{\sim}32\;Gy$) in 7 fractions. The median cumulative biologic effective dose (BED) at point A (EBRT+ICBT) was $88\;Gy_{10}$ (range: $77{\sim}94\;Gy_{10}$). The median cumulative BED at ICRU 38 reference point (EBRT+ICBT) was $131\;Gy_3$ (range: $122{\sim}140\;Gy_3$) at point A, $109\;Gy_3$ (range: $88{\sim}125\;Gy_3$) at the rectum and $111\;Gy_3$ (range: $91{\sim}123\;Gy_3$) at the urinary bladder. Cisplatin ($60\;mg/m^2$) and 5-FU ($1,000\;mg/m^2$) was administered intravenously at 3 weeks interval from the first day of radiation for median 5 (range: $2{\sim}6$) cycles. The assessment was performed at 1 month after completion of radiation therapy by clinical examination and CT scan. The median follow-up time was 36 months (range: $8{\sim}50$ months). $\underline{: The complete response rate after concurrent chemoradiation therapy was 93.3%. The 3-yr actuarial pelvic control rate was 87% and 3-yr actuarial overall survival and disease-free survival rate was 93% and 87%, respectively. The local failure rate was 13% and distant metastatic rate was 3.3%. The crude rate of minor hematologic complications (RTOG grade 1-2) occurred in 3 patients (10%) and one patient had suffered from severe leukopenia (RTOG grade 4) during concurrent treatment. Acute minor enterocolitis (RTOG grade 1-2) occurred in 11 patients (37%) and one patient (3%) was suffered from colon perforation during radiation therapy. Late colitis of RTOG grade 1 occurred in 5 patients (15%). Acute cystitis of RTOG grade 1 occurred in 12 patients (40%) and late cystitis of RTOG grade 2 occurred in one patient (3%). No treatment related death was seen. $\underline{Conclusion}$: The results of this study suggest that the concurrent chemoradiation therapy with HDR brachytherapy could be accepted as an effective and safe treatment for cervical cancer.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.186-193
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• 2005

Purpose: To improve the management of a medical linear accelerator, the records of operational failures of a Varian CL2l00C over a ten year period were retrospectively analyzed. Materials and Methods: The failures were classified according to the involved functional subunits, with each class rated Into one of three levels depending on the operational conditions. The relationships between the failure rate and working ratio and between the failure rate and outside temperature were investigated. In addition, the average life time of the main part and the operating efficiency over the last 4 years were analyzed. Results: Among the recorded failures (total 587 failures), the most frequent failure was observed in the parts related with the collimation system, including the monitor chamber, which accounted for $20\%$ of all failures. With regard to the operational conditions, 2nd level of failures, which temporally interrupted treatments, were the most frequent. Third level of failures, which interrupted treatment for more than several hours, were mostly caused by the accelerating subunit. The number of failures was increased with number of treatments and operating time. The average life-times of the Klystron and Thyratron became shorter as the working ratio increased, and were 42 and $83\%$ of the expected values, respectively. The operating efficiency was maintained at $95\%$ or higher, but this value slightly decreased. There was no significant correlation between the number of failures and the outside temperature. Conclusion: The maintenance of detailed equipment problems and failures records over a long period of time can provide good knowledge of equipment function as well as the capability of predicting future failure. Wore rigorous equipment maintenance Is required for old medical linear accelerators for the advanced avoidance of serious failure and to improve the qualify of patient treatment.

• 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.

• Applied Microscopy
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• v.30 no.1
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• pp.45-59
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• 2000

Cis-platin is a widely used anticancer drug against certain solid tumors such as malignant ovarian tumor, malignant carcinoma of head and neck, bladder cancer and cervical cancer of uterus, and its major mechanism of action is inhibition of DNA synthesis of the tumor cell. To investigate the inhibitory effects of cis-platin on the ciliogensis of the ciliated cells in the mucosa of oviduct, the author pursued the alterations of $\alpha-tubulin$, which is the main constituent of the microtubles in cilia, after cis-platin treatment. To eliminate the possible variations due to ovarian cycle, female Spargue-Dawley rats ($150\sim200gm$ in B.W.) were pretreated with estradiol benzoate (20 mg/kg, once a day, for 4 consecutive days). Animals were administrated with cis-platin (6 mg/kg, i.p.) and sacrificed at 1day, 3days, 5days and 7days after treatment, respectively. Immunohistochemistry for $\alpha-tubulin$ using mouse anti-rat $\alpha-tubulin$ monoclonal antibody as primary antibody was done. Immunogold electronmicroscopy for intracellular distributions of $\alpha-tubulin$ was also performed with same primary antibody and Goat anti- mouse IgM which is preconjugated with gold particles of 15 nm as secondary antibody. The results obtained were as follows; 1. Strong immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1, 3 and 5 days after estradiol pretreatment. 2. Weak immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1 and 3 days after cis-platin treatment but it was recovered to strong immunoreactivity in 5 days 3. In immunogold electronmicroscopy, density of gold particles for $\alpha-tubulin$ reactions was decreased in apical cytoplasm, but few changes were observed in basal body or cilia at 1 and 3 days after cis-platin treatment. From these above results, it is indicated that synthesis of $\alpha-tubulin$ in ciliated cells of rat oviduct is inhibited by cis-platin treatment.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.167-175
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• 1998

Purpose : It is not a simple task to achieve the ideal isodose curve with a standard vaginal applicator or sing1e plane needle impant in the paravaginal tissue when primary or recurrent gynecological neoplasms(cervical cancers, vaginal cancers and vulvar cancers) are treated as a boost following external beam radiotherapy. The authors introduce the development and construction of a simple, inexpensive, customized applicator for volume implant to maximize the radiation dose to the tumor while minimizing the dose to the rectum and the bladder. Materials and Methods : Nine patients underwent Ir-192 transperineal interstitial implantation for either recurrent(5 cases) or primary(3 cases) cervical cancers or primary vaginal cancer(1 case) between August 1994 and February 1998 at Ajou university hospital. First 3 cases were performed with a sing1e plane implant guided by digital palpation. Because of inadequate isodose coverage in the tumor volume in first 3 cases, we designed and constructed interstitial vaginal applicator for volume implant to improve tumor dose distribution and homogeneity while sparing the surrounding normal tissue. Our applicators consist of vaginal obturator and perineal template that made of the clear acrylamide and dental mold material$(Provil^{(R)})$. The applicators were customized individually according to the tumor size and its location Both HDR and LDR irradiation were given with these applicators accomodating 6 Fr needles(Microselectron Nucletron). The pretreatment planning prior to actual implant was performed whenever possible. Results : Needles can be inserted easily and evenly into the tumor volume through the holes of templates, requiring less efforts and time for the implant procedure. Our applicators made of materials available from commercial vendors. These have an advantage that require easy procedure, and spend relatively short time to construct. Also it was possible to fabricate applicators to individualize according to the tumor size and its location and to achieve the ideal isodose coverage. We found an accurate needle arrangement and ideal dose distribution through the CT scan that was obtained in 3 cases after needle implant. Three patients with primary cervical and vaginal cancers were controlled locally at final follow up. But all recurrent cases failed to do so. Conclusion : The authors introduce inexpensive, simple interstitial vaginal templates which were self-designed and constructed using materials available from commercial vendors such as acrylanide and dental mold material $(Provil^{(R)})$.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.1
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• pp.29-37
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• 2004

Purpose : A rectum and a bladder should be carefully considered in order to decrease side effects when HDR patient of uterine cervix cancer. Generally speaking, the value of dosimeter at a rectum and a bladder only depends on the value of a planning equipment, while some analyses of the value of dosimetry at rectum with TLD has been reported Or the contrary, it is hardly to find a report with in vivo dosimetry(diode detector). On this thesis, we would like to suggest the following. When a patient of uterine cervix cancer is in therapy, it is helpful to put a diode detector inside of a rectum in order to measure the rectal dose Based upon the result of the dosimetry, the result can be used as basic data at decreasing side effects. Materials and Methods : Six patients of uterine cervix cancer(four with tandem and ovoid, one with cylinder, and the other one with tandem and cylinder) who had been irradiated with HDR. Ir-192 totally 28 times from February 2003 to June 2003. We irradiated twice in the same distant spots with anterior film and lateral film whenever we measured with a diode detector. Then we did planning and compared each film. Results : The result of the measurement 4 patients with a diode detector is the following. The average and deviation from 3 patients with tandem and ovoid were $274.1{\pm}13.4cGy$, from 1 patient with tandem and ovoid were $126.1{\pm}7.2cGy$, from 1 patient with cylinder were $99.7{\pm}7.1cGy$, and from 1 patient with tandem and cylinder were $77.7{\pm}11.5cGy$. Conclusion : It is difficult to predict how the side effect of a rectum since the result of measurement with a diode detector depends on the state of a rectum. According to the result of the study, it is effective to use a TLD or an in vivo dosimetry and measure a rectum in order to consider the side effect. It is very necessary to decrease the amount of irradiation by controlling properly the duration of the irradiation and gauze packing, and by using shield equipments especially when side effects can be expected.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.271-276
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• 1991

A series of 510 patients with carcinoma of the uterine cervix given the curative radiation therapy from March 1979 through December 1986 was evaluated to determine the value of intravenous pyelography (IVP), cystoscopy, sigmoidoscopy, and abdomino-pelvic CT as staging work-up prior to treatment. On IVP and cystoscopy, $10.7\%$(49/456) and $5.3\%$(24/452) showed abnormality, respectively, but only $0.7\%$(3/413) did on sigmoidoscopy. As a result of these work-ups prerequisite to FIGO staging, twenty six ($5.1\%$) out of 510 patients were upstaged from the stage determined by the findings of physical examination alone. The proportions of upstaging in each stage were as follows; none in stage IB (35), IIA (89) and IIIA (8), $7.9\%$(20/252) in stage IIB (14 patients to FIGO stage IIIB, 6 patients to FIGO stage IVA), and $4.8\%$(6/126) in stage IIIB (all to FIGO stage IVA). Positive findings of staging work-ups were found only in patients with advanced stages of stage IIB or over determined by physical examination alone but not in those with earlier stages. CT was performed in 337 patients. CT detected pelvic lymph node (LN) enlargement in $25.2\%$ (85/337) and paraaortic LN enlargement in $7.4\%$(25/337). Pelvic LN positivity was well correlated with increasing stage but paraaortic LN positivity was not. In the evaluation of parametrial involvement, CT findings were in accordance with those of physical examination only in $65.6\%$ (442/674). When compared with endoscopic studeies, CT had much lower positive predictive value than negative predicitive value in the evaluation of adjacent organ invasion. The staging work-ups should be individualized by the disease extent of each patient, and then the efficiency of work-uus may be increased without compromising the appropriate FIGO staging and treatment.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.143-156
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• 2005

Background: The best dose-fractionation regimen of the definitive radiotherapy for cervix cancer remains to be clearly determined. It seems to be partially attributed to the complexity of the affecting factors and the lack of detailed information on external and intra-cavitary fractionation. To find optimal practice guidelines, our experiences of the combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) were reviewed with detailed information of the various treatment parameters obtained from a large cohort of women treated homogeneously at a single institute. Materials and Methods: The subjects were 743 cervical cancer patients (Stage IB 198, IIA 77, IIB 364, IIIA 7, IIIB 89 and IVA 8) treated by radiotherapy alone, between 1990 and 1996. A total external beam radiotherapy (EBRT) dose of $23.4\~59.4$ Gy (Median 45.0) was delivered to the whole pelvis. High-dose-rate intracavitary brachytherapy (HDR-IBT) was also peformed using various fractionation schemes. A Midline block (MLB) was initiated after the delivery of $14.4\~43.2$ Gy (Median 36.0) of EBRT in 495 patients, while In the other 248 patients EBRT could not be used due to slow tumor regression or the huge initial bulk of tumor. The point A, actual bladder & rectal doses were individually assessed in all patients. The biologically effective dose (BED) to the tumor ($\alpha/\beta$=10) and late-responding tissues ($\alpha/\beta$=3) for both EBRT and HDR-ICBT were calculated. The total BED values to point A, the actual bladder and rectal reference points were the summation of the EBRT and HDR-ICBT. In addition to all the details on dose-fractionation, the other factors (i.e. the overall treatment time, physicians preference) that can affect the schedule of the definitive radiotherapy were also thoroughly analyzed. The association between MD-BED $Gy_3$ and the risk of complication was assessed using serial multiple logistic regression models. The associations between R-BED $Gy_3$ and rectal complications and between V-BED $Gy_3$ and bladder complications were assessed using multiple logistic regression models after adjustment for age, stage, tumor size and treatment duration. Serial Coxs proportional hazard regression models were used to estimate the relative risks of recurrence due to MD-BED $Gy_{10}$, and the treatment duration. Results: The overall complication rate for RTOG Grades $1\~4$ toxicities was $33.1\%$. The 5-year actuarial pelvic control rate for ail 743 patients was $83\%$. The midline cumulative BED dose, which is the sum of external midline BED and HDR-ICBT point A BED, ranged from 62.0 to 121.9 $Gy_{10}$ (median 93.0) for tumors and from 93.6 to 187.3 $Gy_3$ (median 137.6) for late responding tissues. The median cumulative values of actual rectal (R-BED $Gy_3$) and bladder Point BED (V-BED $Gy_3$) were 118.7 $Gy_3$ (range $48.8\~265.2$) and 126.1 $Gy_3$ (range: $54.9\~267.5$), respectively. MD-BED $Gy_3$ showed a good correlation with rectal (p=0.003), but not with bladder complications (p=0.095). R-BED $Gy_3$ had a very strong association (p=<0.0001), and was more predictive of rectal complications than A-BED $Gy_3$. B-BED $Gy_3$ also showed significance in the prediction of bladder complications in a trend test (p=0.0298). No statistically significant dose-response relationship for pelvic control was observed. The Sandwich and Continuous techniques, which differ according to when the ICR was inserted during the EBRT and due to the physicians preference, showed no differences in the local control and complication rates; there were also no differences in the 3 vs. 5 Gy fraction size of HDR-ICBT. Conclusion: The main reasons optimal dose-fractionation guidelines are not easily established is due to the absence of a dose-response relationship for tumor control as a result of the high-dose gradient of HDR-ICBT, individual differences In tumor responses to radiation therapy and the complexity of affecting factors. Therefore, in our opinion, there is a necessity for individualized tailored therapy, along with general guidelines, in the definitive radiation treatment for cervix cancer. This study also demonstrated the strong predictive value of actual rectal and bladder reference dosing therefore, vaginal gauze packing might be very Important. To maintain the BED dose to less than the threshold resulting in complication, early midline shielding, the HDR-ICBT total dose and fractional dose reduction should be considered.