• 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.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.261-267
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• 1986

Development of supervoltage treatment machine may minimize skin reaction by skin-sparing effect, but skin damage is still one of "the dose limiting factor" in radiation therapy. In spite of these importance, systemic histopathologic studies of skin in similar conditions which used in clinical treatment has not been performed so far. 60mice were irradiated with conventional fraction ($200{\times}5/wk$) and whole abdominal field ($2{\times}3cm$, from symphysis pubis to xyphoid process). Used machine was 250KV, 24mA, orthovoltage x-ray machine. Histopathological changes of acute skin reaction at the level of total irradiation dose were analyzed and the possible mechanism of later chronic changes were investigated. Obtained results are as follows: 1. In 1,000 rad irradiated group, only mild epidermal edema is noted. 2. In 2,000 rad irradiated group, slightly decreased number and size of hair follicles and appendages, dermal edema and scanty infiltration of inflammatory cells are visible. 3. In 3,000 rad irradiated group, marked increased capillary congestion and prominant infiltration of inflammatory cells are observed. 4. In 4,000 rad irradiated group, vascular wall thickening with proliferation of endothelial cells are prominant. Dermal thinning and hyalinization are newly developed. 5. In 5,000 rad irradiated group, complete desquamation of epidermis is not seen, despite of acceleration of all above mentioned changes.

• Radiation Oncology Journal
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• v.22 no.2
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• pp.130-137
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• 2004

Purpose : In radiotherapy for cervix cancer, both 3-dimensioal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) could reduce the dose to the small bowel (SB), while the small bowel displacement system (SBDS) could reduce the SB volume in the pelvic cavity. To evaluate the effect of the SBDS on the dose to the SB in 3D-CRT and IMRT plans, 3D-CRT and IMRT plans, with or without SBDS, were compared. Materials and Methods : Ten consecutive uterine cervix cancer patients, receiving curative radiotherapy, were accrued. Ten pairs of computerized tomography (CT) scans were obtained in the prone position, with or without SBDS, which consisted of a Styrofoam compression device and an individualized custom-made abdominal immobilization device. Both 3D-CRT, using the 4-field box technique, and IMRT plans, with 7 portals of 15 MV X-ray, were generated for each CT image, and proscribed 50 Gy (25 fractions) to the isocenter. For the SB, the volume change due to the SBDS and the DVHs of the four different plans were analyzed using palled t-tests. Results : The SBDS significantly reduced the mean SB volume from 522 to 262 cm$^{3}$ (49.8$\%$ reduction). The SB volumes that received a dose of 10$\~$50 Gy were significantly reduced in 3D-CRT (65$\~$80$\%$ reduction) and IMRT plans (54$\~$67$\%$ reduction) using the SBDS. When the SB volumes that received 20$\~$50 Gy were compared between the 3D-CRT and IMRT plans, those of the IMRT without the SBDS were significantly less, by 6$\~$7$\%$, than those for the 3D-CRT without the SBDS, but the volume difference was less than 1$\%$ when using the SBDS. Conclusion : The SBDS reduced the radiation dose to the SB in both the 3D-CRT and IMRT plans, so could reduce the radiation injury of the SB.

• Radiation Oncology Journal
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• v.4 no.1
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• pp.75-80
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• 1986

Heterotopic bone formation is a complication which occurs in 0.6 to $61.7\%$ of patients after total hip replacement arthroplasty. We reviewed 4 patients (8 hips) who received postoperative irradiation on their hi ps for prevention of heterotopic bone formation in the Department of Therapeutic of Therapeutic Radiology, Seoul National University versify Hospital from January 1981 through August 1985. Radiation therapy was started 6 to 10 days postoperatively with the dosage of 2,000 cGy given in 10 fractions. As a result, 7 hips had Grade 0 and 1 hip had Grade 1 heterotopic ossification according to modified Blocker system. Our result and review of the literatures strongly support that the postoperative radiotherapy is effective for prevention of heterotopic bone formation in high risk group.

• Progress in Medical Physics
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• v.13 no.3
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• pp.114-119
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• 2002

A immobilizing device that is essential for correct lung and lens shielding with homogenous dose distribution in fractionated total body irradiation was developed and it's efficiency was evaluated. The main frame was made of stainless steel bar (5 cm in diameter) to withstand up to 230 cm in height and 100 kg in weight to prevent any injury even in unconsciousness condition. The saddle was designed to adjust the body weight and hight of standing patients. Chest and back supporter were made of 1 cm acryl which could fix the lung block and cassette holder. Leather and sponge pedding were used for head rest to keep patients comfortable. The device was strongly fixed by specially designed bolts on the bottom panel which was made of 1 cm stainless steel and 10 cm thick wooden board. Precise manipulation ($\pm$2 mm) was possible by upper two pulleys and side handles. Average four minutes twenty five seconds were needed for exact setting in fractionated TBI. No significant difference of lung block location on repeated verification films was confirmed and relatively homogeneous dose distribution was measured in rando phantom experiments and patient treatments ($\pm$5%). This immobilizing device was very efficient to keep correct position of patients, which is essential for better result and less complication in fractionated TBI.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.192-198
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• 2003

Purpose: Current results of autologous stem cell transplantation (SCT) suggest that this procedure may prolong disease free survival In patients with acute myeloid leukemia (AML). Autologous SCT is increasingly used as treatment for AML in first remission. The aim of this study was to evaluate the outcome of autologous SCT for patients with AML in first remission treated by autologous SCT using cytarabine, melphalan and total body irradiation (TBI) as the conditioning regimen. Materials and Methods: Between January 1995 and December 1999, 29 patients with AML in first remission underwent autologous SCT. The median age of patients was 33 years (range, 16 to 47). The conditioning regimen consisted of cytarabine ($3.0\;gm/m^2$ for 3 days), melphalan ($100\;gm/m^2$ for 1 day) and TBI (total 1000 cGy in five fractions over 3 days). Results: The median follow up was 40 months with a range of 3 to 58 months. The 4-year cumulative probability of disease free survival was 69.0%, and median survival was 41.5 months. The 4-year relapse rate was 27.6%. The factor Influencing disease free survival and relapse rate was the French-American-British (FAB) classification ($M_3$ group vs. other groups; p=0.048, p=0.043). One patient died from treatment-related toxicity. Conclusion:: Although the small number of patients does not allow us to draw any firm conclusion, our results were encouraging and suggest that the association of cytarabine, melphalan and TBI as a conditioning regimen for autologous SCT for AML on first remission appears to be safe and effective.

• Progress in Medical Physics
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• v.24 no.4
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• pp.278-283
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• 2013

Breast cancer is the leading cause of cancer death in women worldwide and the number of women breast cancer patient was increased continuously. Most of breast cancer patient has suffered from unnecessary radiation exposure to heart, lung. Low radiation dose to the heart could lead to the worsening of preexisting cardiovascular lesions caused by radiation induced pneumonitis. Also, several statistical reports demonstrated that left-sided breast cancer patient showed higher mortality than right-sided breast cancer patient because of heart disease. In radiation therapy, Deep Inspiration Breath Hold (DIBH) technique which the patient takes a deep inspiration and holds during treatment and could move the heart away from the chest wall and lung, has showed to lead to reduction in cardiac volume and to minimize the unnecessary radiation exposure to heart during treatment. In this study, we investigated the displacement of heart using DIBH CT data compared to free-breathing (FB) CT data and radiation exposure to heart. Treatment planning was performed on the computed tomography (CT) datasets of 10 patients who had received lumpectomy treatments. Heart, lung and both breasts were outlined. The prescribed dose was 50 Gy divided into 28 fractions. The dose distributions in all the plans were required to fulfill the International Commission on Radiation Units and Measurement specifications that include 100% coverage of the CTV with ${\geq}95%$ of the prescribed dose and that the volume inside the CTV receiving >107% of the prescribed dose should be minimized. Scar boost irradiation was not performed in this study. Displacement of heart was measured by calculating the distance between center of heart and left breast. For the evaluation of radiation dose to heart, minimum, maximum and mean dose to heart were calculated. The present study demonstrates that cardiac dose during left-sided breast radiotherapy can be reduced by applying DIBH breathing control technique.

• Radiation Oncology Journal
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• v.3 no.2
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• pp.153-157
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• 1985

Radiation effect on mammals, especially on hematologic changes, has been studied since discovery of x-ray. Various experimental animals were tried for radiobiological studies. 72hybrid mice with conventional faction $(15\times/week)$, large abdominal field $12\times3cm$, from symphysis pubic to xyphoid process) were used. Body weight was declined gradually by increasing irradiation doses, nadir was about $29.7\%$ in male; $30.4\%$ in female at 6000 rad irradiation group. Hemoglobin value was nearly normal throughout entire treatment. Significant dropping of WBC count was noted to $40-50\%$ of pretreatment values by only 1000rad irradiation. Change of differential count was interesting; : lymphocyte proportion showed gradual reduction, instead of gradual increasing of segmented neutrophil. Those proportion were reversed after 6000 rad irradiation. Urinary protein tests showed + - +++, showing no correlation with dosage. Application of our study in clinical combination therapy (radiation + chemotherapy) was discussed.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.280-288
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• 2008

Purpose: To identify the inter-fractional shift pattern and to assess an adequate treatment margin in the radiotherapy of a liver tumor using mega-voltage computed tomography (MVCT) of a tomotherapy unit. Materials and Methods: Twenty-six patients were treated for liver tumors by tomotherapy from April 2006 to August 2007. The MVCT images of each patient were analyzed from the $1^{st}$ to the $10^{th}$ fraction for the assessment of the daily liver shift by four groups based on Couinard's proposal. Daily setup errors were corrected by bony landmarks as a prerequisite. Subsequently, the anterior-, posterior-, right-, and left shifts of the liver edges were measured by maximum linear discrepancies between the kilo-voltage computed tomography (KVCT) image and MVCT image. All data were set in the 2-dimensional right angle coordinate system of the transverse section of each patient's body. Results: The liver boundary shift had different patterns for each group. In group II (segment 2, 3, and 4), the anterior mean shift was $2.80{\pm}1.73\;mm$ outwards, while the left mean shift was $2.23{\pm}1.37\;mm$ inwards. In group IV (segment 7 and 8), the anterior-, posterior-, right-, and left mean shifts were $0.15{\pm}3.93\;mm$ inwards, $3.15{\pm}6.58\;mm$ inwards, $0.60{\pm}3.58\;mm$ inwards, and $4.50{\pm}5.35\;mm$ inwards, respectively. The reduced volume in group II after MVCT reassessment might be a consequence of stomach toxicity. Conclusion: Inter-fractional liver shifts of each group based on Couinard's proposal were somewhat systematic despite certain variations observed in each patient. The geometrical deformation of the liver by respiratory movement can cause shrinkage in the left margins of liver. We recommend a more sophisticated approach in free-breathing mode when irradiating the left lobe of liver in order to avoid stomach toxicity.

• Radiation Oncology Journal
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• v.11 no.1
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• pp.79-82
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• 1993

From October 1989 to March 1992, ten patients diagnosed as primary central nervous system (CNS) lymphoma were treated with radiation therapy at Asan Medical Center. To obtain pathologic diagnosis, five patients had stereotactic biopsy and the others underwent craniotomy & tumor removal. According to the classification by International Working Formulation, seven of 10 patients showed diffuse large cell types and the remaining 3 had diffuse mixed cell types. Computed tomographic scans of the brain disclosed solitary (6 cases) or multiple (4 cases) intracranial lesions. All patients received 4000 cGy/20 fx to the whole brain followed by an additional 2000 cGy/10 fx boost to the primary lesion. Six patients with initial cerebrospinal fluid (CSF involvement were treated with whole brain irradiation and intrathecal Methotrexate (IT-MTX) chemotherapy. One of them received an additional spinal irradiation after 3 cycles of IT-MTX chemotherapy because of MTX induced arachnoiditis. One patient received 3 cycles of systemic chemotherapy prior to rodiation therapy and one received 5 cycles of salvage chemotherapy for recurrence. With a median follow up time of 8 months, all patients were followed from 7 to 26 months. Radiologically seven patients showed complete remission and the remaining three showed partial remission at one month after radiotherapy. The 1 and 2 year survival rate was $86{\%}\;and\;69{\%}$ respectively. Until now, two patients expired at 7 and 14 months. These patients developed extensive CSF seeding followed by local failure. Considering initial good response to radiation therapy and low incidence of extraneural dissemination in primary CNS lymphoma, we propose to increase total tumor dose to the primary lesion by hyperfractionated radiotherapy or stereotactic radiosurgery. For the patients with CSF involvement at diagnosis, we propose craniospinal irradiation with IT MTX chemotherapy.