Radiation Oncology Journal最新文献

Purpose: This study was conducted to evaluate prognosis of patients with level I/II axillary lymph node metastases from occult breast cancer (OBC).

Materials and methods: Data of 53 patients with OBC who received axillary lymph node dissection (ALND) positive/negative (+/-) breast-conserving surgery between 2001 and 2013 were retrospectively collected at seven hospitals in Korea. The median number of positive lymph nodes (+LNs) was 2. Seventeen patients (32.1%) had >3 +LNs. A total of 48 patients (90.6%) received radiotherapy. Extents of radiotherapy were as follows: whole-breast (WB; n = 11), regional lymph node (RLN; n = 2), and WB plus RLN (n = 35).

Results: The median follow-up time was 85 months. Recurrence was found in four patients: two in the breast, one in RLN, and one in the breast and RLN. The 5-year and 7-year disease-free survival (DFS) rates were 96.1% and 93.5%, respectively. Molecular subtype and receipt of breast radiotherapy were significantly associated with DFS. Patients with estrogen receptor negative, progesterone receptor negative, and human epidermal growth factor receptor 2 negative (ER-/PR-/HER2-) subtype had significantly lower 7-year DFS than those with non-ER-/PR-/HER2- tumor (76.9% vs. 100.0%; p = 0.03). Whole breast irradiation (WBI) was significantly associated with a higher 7-year DFS rate (94.7% for WBI group vs. 83.3% for non-WBI group; p = 0.01). Other factors including patient's age, number of +LNs, taxane chemotherapy, and RLN irradiation were not associated with DFS.

Conclusion: Patients with OBC achieved favorable outcome after ALND and breast-targeting treatment. Molecular subtype and receipt of WBI was significant factors for DFS.

The abscopal effect is a phenomenon in which radiation therapy results in the regression of metastatic lesions at a distance from the irradiated lesions. Here, we have described a 37-year-old woman with advanced luminal B breast cancer who presented with severe pain at multiple sites. Multiple bone, lymph node, and lung metastases were found on computed tomography (CT). She refused to receive any systemic therapy, but she agreed to receive palliative radiotherapy (RT). Multi-site RT (25 or 30 Gy in 5 fractions) was performed for pain palliation. The pain was completely relieved after RT. Furthermore, the pulmonary CT after 3 months of RT showed a dramatic regression of the previous multiple lung metastases. This is the case report demonstrating the abscopal effect in South Korea.

Purpose: Portal vein tumor thrombosis (PVTT) from cancer involving the liver carries a dismal prognosis, with median overall survival (OS) ranging from 2 to 5 months. While treatment with yttrium-90 (90Y) radioembolization alone may improve outcomes, overall prognosis remains poor. We hypothesize that the combination of 90Y radioembolization to the parenchymal component of the tumor and stereotactic body radiation therapy (SBRT) to the vascular component is a safe and effective means of improving outcomes.

Materials and methods: A single center retrospective review identified 12 patients with cancers involving the liver who received both 90Y radioembolization and SBRT to the PVTT between May 2015 to August 2020. Primary endpoint was the 90-day toxicity rate by the Common Terminology Criteria for Adverse Events version 5.0. Secondary endpoints were the best response rate based on the Response Evaluation Criteria in Solid Tumors v1.1, local control rate, portal vein (PV) patency rate, and median OS.

Results: Patients received a median 90Y dose of 104.3 Gy (range, 83.3 to 131.7 Gy) and a median 5-fraction SBRT dose of 32.5 Gy (range, 27.5 to 50 Gy). There were no late toxicities reported, and only 7 acute grade 1 toxicities reported: elevation of liver function tests (17%), nausea (17%), fatigue (17%), and esophagitis (8%). Local control was 83%. 58% of patients had a patent PV after treatment. With a median follow-up time of 28 months, 1-year OS was 55% with a median OS of 14 months.

Conclusion: Combination 90Y radioembolization and SBRT appears to be safe and effective in the treatment of PVTT. Larger prospective studies are warranted to better evaluate this combination treatment approach.

Purpose: To analyze rectal dose and changes in quality of life (QOL) measured with the Expanded Prostate and Cancer Index Composite (EPIC) bowel domain in patients being treated for prostate cancer with curative-intent proton beam therapy (PBT) within a large single-institution prospective registry.

Materials and methods: Data was collected from 243 patients with localized prostate cancer treated with PBT from 2016 to 2018. The EPIC survey was administered at baseline, end-of-treatment, 3, 6, and 12 months, then annually. Dose-volume histogram (DVH) parameters for the rectum were computed, and rectal dose was analyzed using BED (α/β = 3), EQD2Gy, and total dose. Repeated measures mixed models were implemented to determine the effect of patient, clinical, and treatment factors (including DVH) on patient-reported bowel symptom burden (EPIC-Bowel).

Results: Treatment overall resulted in changes in EPIC-Bowel scores (baseline score = 93.7), most notably at end-of-treatment (90.6) and 12 months (89.7). However, they returned to baseline at 36 months (92.9). On multivariate modeling, rectal BED D25 (Gy) ≥23% was significantly associated with decline in QOL scores measuring bother (p < 0.01; 4.06 points different).

Conclusion: Rectal doses, specifically BED D25 (Gy) ≥23%, are significantly associated with decline in bowel bother-related QOL in patients undergoing definitive radiotherapy for localized prostate cancer. This study demonstrates BED as an independent predictor of bowel QOL across dose fractionations of PBT.

Purpose: The aim of this study was to assess the suitability of using cone-beam computed tomography images (CBCTs) produced in a Leksell Gamma Knife (LGK) Icon system to generate electron density information for the convolution algorithm in Leksell GammaPlan (LGP) Treatment Planning System (TPS).

Materials and methods: A retrospective set of 30 LGK treatment plans generated for patients with multiple metastases was selected in this study. Both CBCTs and fan-beam CTs were used to provide electron density data for the convolution algorithm. Plan quality metrics such as coverage, selectivity, gradient index, and beam-on time were used to assess the changes introduced by convolution using CBCT (convCBCT) and planning CT (convCT) data compared to the homogeneous TMR10 algorithm.

Results: The mean beam-on time for TMR10 and convCBCT was found to be 18.9 ± 5.8 minutes and 21.7 ± 6.6 minutes, respectively. The absolute mean difference between TMR10 and convCBCT for coverage, selectivity, and gradient index were 0.001, 0.02, and 0.0002, respectively. The calculated beam-on times for convCBCT were higher than the time calculated for convCT treatment plans. This is attributed to the considerable variation in Hounsfield values (HU) dependent on the position within the field of view.

Conclusion: The artifacts from the CBCT's limited field-of-view and considerable HU variation need to be taken into account before considering the use of convolution algorithm for dose calculation on CBCT image datasets, and electron data derived from the onboard CBCT should be used with caution.

Purpose: In radiotherapy for head and neck cancer, it is crucial to define the appropriate treatment volume to determine treatment outcome and toxicity. We examined the feasibility of omitting elective high retropharyngeal lymph node (RPLN) irradiation in patients with oropharyngeal cancer.

Materials and methods: We performed a retrospective review of 189 patients with oropharyngeal squamous cell carcinoma who were treated with definitive or postoperative radiation therapy between 2009 and 2016. Of them, 144 (76.2%) underwent ipsilateral RPLN irradiation up to the superior border of the C1 vertebral body, while the other 45 (23.8%) were irradiated up to the transverse process of the C1 vertebra. High RPLN-treated and spared group were propensity matched based on key clinical variables.

Results: During the follow-up period, only three patients (one in the high RPLN-treated group and two in the high RPLN-spared group) developed RPLN recurrence. There were no significant between-group differences in 5-year locoregional failure-free survival (82.8% vs. 90.6%; p = 0.14), distant metastasis-free survival (93.1% vs. 93.3%; p = 0.98) and RPLN failure-free survival (99.3% vs. 95.0%; p = 0.09). In the matched groups, high RPLN-spared patients received a lower mean ipsilateral parotid gland dose (mean, 20.8 Gy vs. 29.9 Gy; p < 0.001) and had a lower incidence of chronic xerostomia (grade 0, 43.5% vs. 13.0%; p = 0.023) at 1 year after radiotherapy compared with high RPLN-treated patients.

Conclusion: Omission of ipsilateral high RPLN irradiation seems safe, and reduces the incidence of chronic xerostomia in patients with oropharyngeal squamous cell carcinoma.

Lacrimal gland adenoid cystic carcinomas are rare, aggressive orbital tumors characterized by poor overall prognosis, tendency for local recurrence and metastasis despite aggressive treatment. Treatment continues to be controversial. Many authorities today will often initiate surgery (orbital exenteration with or without bone removal vs. globe-sparing resection) and adjuvant radiotherapy (external beam or proton beam therapy). We introduce a case of lacrimal gland adenoid cystic carcinoma treated with orbital exenteration and adjuvant volumetric modulated arc therapy, and discuss the related literature.

Purpose: About 40% of men diagnosed with prostate cancer (Pca) are ≤65 years of age. This study evaluates the risk of second cancer among young Pca patients treated with surgery or radiation.

Materials and methods: This is a retrospective review of 150,915 men aged ≤65 years at Pca diagnosis treated with surgery or radiation registered in the Surveillance, Epidemiology, and End Results (SEER) database between 1973 and 2014. Incidence rates of second rectum/rectosigmoid junction (RJ), bladder, and lung cancer in each treatment group were reported with adjustment for potential confounders. Cumulative incidence functions were used to summarize the risk of second cancer after completing initial treatment.

Results: Men treated with external beam radiation (BEAM), brachytherapy (SEED), or combined radiation all exhibited a statistically significant increased incidence of second bladder cancer compared to men treated with surgery (adjusted incidence rate ratio [IRR]: 2.09, 1.91, and 2.04, respectively). Incidence of rectum/RJ cancer was also significantly increased in men receiving BEAM and combined radiation (adjusted IRR: 1.58 and 1.98, respectively). There were also significant differences in the cumulative incidence of second bladder cancer after receiving any form of radiation compared to surgery.

Conclusion: Pca survivors ≤65 years of age at Pca diagnosis had an increased risk of second bladder and rectum/RJ cancer after BEAM and combined radiation treatment after adjusting for confounding factors. Second bladder cancer incidence after either form of radiation treatment was increased even at 5 years after a Pca diagnosis.

Purpose: The aim of this study is to evaluate the treatment responses of Kaposi sarcoma patients treated with radiotherapy (RT).

Materials and methods: The data of 18 patients (40 different regions) who were treated for Kaposi sarcoma in OOOO between March 23, 2010 to February 13, 2018 were evaluated retrospectively. The primary endpoint of the study was the clinical-subjective response after RT, and the secondary endpoint was the visual response assessment after RT.

Results: In evaluating the patients' reported response of the lesions: 25 (62.5%) of complete response (CR), 12 (30%) of partial response (PR), and stable response was seen in 3 patients (7.5%). Patient reported response after RT was significantly higher in male sex (p = 0.002; odds ratio [OR] = 13.8, 95% confidence interval [CI], 2.7-70.0). Physician reported response rates were available for 28 lesions and CR was detected in 12 lesions (30%); PR was observed in 16 (40%). The relationship between physician reported outcome and RT techniques (electron, bolus, or water bolus) is close to the limit of statically significance (p = 0.052). Fewer lesions disappeared in patients with photon preference than electrons (p = 0.036; OR = 0.093; 95% CI, 0.009-0.950). Patients' reported complete response rates were significantly higher in the 20 Gy per 5 fractions treatment arm (p = 0.042; OR = 1.75; 95% CI, 1.1-2.7).

Conclusion: RT is an effective local treatment with high response rates in the treatment of Kaposi sarcoma. The subjective-clinical response rate was higher in male sex and the visual response was higher in the 20 Gy per 5 fractions arm. Additional studies are needed to standardize RT dose and techniques.

Purpose: This study investigated the possible radioprotective effect of Costus afer extract (CAE) on hematological and histopathological parameters of mice.

Materials and methods: Fifty-four male mice with mass between 37-43 g, 11-13 weeks old were used for this study. We divided the mice into six different groups containing nine animals, which were then further sub-divided into irradiated groups and un-irradiated groups. Animals received 250 mg/kg body weight extract of CAE by oral gavage for 6 days in addition to feeding and water ad libitum. Animals in the irradiated group were exposed to radiation at the Department of Radiotherapy and Oncology, Grey's Hospital using a linear accelerator. Blood samples were collected at 48-hour post-irradiation for the hematology test followed by histopathology examination of kidney and liver.

Results: Our findings revealed that 3 Gy and 6 Gy dose of X-ray radiation caused a significant reduction in the white blood cell, packed cell volume, hemoglobin, neutrophils, lymphocytes, eosinophils, and platelet counts compared with the control group. However, the administration of CAE before irradiation significantly increased the mentioned parameters. There was no increase in red blood cell and monocyte among treated groups compared with the control. Histopathological changes in the kidney and liver sections revealed that no visible lesion in the pretreated mice. Hepatocytes seem to be within normal histological limits.

Conclusions: This study concludes that CAE offered some protection against radiation-induced hematological alterations, but there was no significant improvement in the histopathological parameters. Thus, further studies are needed to validate its radioprotective effect on histopathological variables.