Byung-Hee Kang, Keun-Yong Eom, Changhoon Song, Jin Ho Kim, Hong-Gyun Wu, In Ah Kim, Jae-Sung Kim
{"title":"Retropharyngeal lymph node-sparing radiotherapy in patients with oropharyngeal carcinoma.","authors":"Byung-Hee Kang, Keun-Yong Eom, Changhoon Song, Jin Ho Kim, Hong-Gyun Wu, In Ah Kim, Jae-Sung Kim","doi":"10.3857/roj.2021.00381","DOIUrl":"https://doi.org/10.3857/roj.2021.00381","url":null,"abstract":"<p><strong>Purpose: </strong>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.</p><p><strong>Materials and methods: </strong>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.</p><p><strong>Results: </strong>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.</p><p><strong>Conclusion: </strong>Omission of ipsilateral high RPLN irradiation seems safe, and reduces the incidence of chronic xerostomia in patients with oropharyngeal squamous cell carcinoma.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e0/b9/roj-2021-00381.PMC8497855.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39497063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kenza Benali, Houda Benmessaoud, Jihan Aarab, Abdelati Nourreddine, Hanan El Kacemi, Sanaa El Majjaoui, Tayeb Kebdani, Noureddine Benjaafar
{"title":"Lacrimal gland adenoid cystic carcinoma: report of an unusual case with literature review.","authors":"Kenza Benali, Houda Benmessaoud, Jihan Aarab, Abdelati Nourreddine, Hanan El Kacemi, Sanaa El Majjaoui, Tayeb Kebdani, Noureddine Benjaafar","doi":"10.3857/roj.2021.00122","DOIUrl":"https://doi.org/10.3857/roj.2021.00122","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/22/3f/roj-2021-00122.PMC8497861.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39494476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hong Zhang, Andrew Yu, Andrea Baran, Edward Messing
{"title":"Risk of second cancer among young prostate cancer survivors.","authors":"Hong Zhang, Andrew Yu, Andrea Baran, Edward Messing","doi":"10.3857/roj.2020.00857","DOIUrl":"https://doi.org/10.3857/roj.2020.00857","url":null,"abstract":"<p><strong>Purpose: </strong>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.</p><p><strong>Materials and methods: </strong>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.</p><p><strong>Results: </strong>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.</p><p><strong>Conclusion: </strong>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.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/9e/6a/roj-2020-00857.PMC8497857.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39497062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Palliative treatment of Kaposi sarcoma with radiotherapy: a single center experience.","authors":"Gonca Altinisik Inan, Ipek Pinar Aral, Suheyla Aytac Arslan, Yilmaz Tezcan","doi":"10.3857/roj.2020.00885","DOIUrl":"https://doi.org/10.3857/roj.2020.00885","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study is to evaluate the treatment responses of Kaposi sarcoma patients treated with radiotherapy (RT).</p><p><strong>Materials and methods: </strong>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.</p><p><strong>Results: </strong>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).</p><p><strong>Conclusion: </strong>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.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/28/70/roj-2020-00885.PMC8024179.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Radioprotective potential of <italic>Costus afer</italic> against the radiation-induced hematological and histopathological damage in mice.","authors":"Idowu Richard Akomolafe, Naven Chetty","doi":"10.3857/roj.2021.00017","DOIUrl":"https://doi.org/10.3857/roj.2021.00017","url":null,"abstract":"<p><strong>Purpose: </strong>This study investigated the possible radioprotective effect of Costus afer extract (CAE) on hematological and histopathological parameters of mice.</p><p><strong>Materials and methods: </strong>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.</p><p><strong>Results: </strong>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.</p><p><strong>Conclusions: </strong>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.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/d9/4a/roj-2021-00017.PMC8024188.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimizing e-learning in oncology during the COVID-19 pandemic and beyond.","authors":"Monica Malik, Deepthi Valiyaveettil, Deepa Joseph","doi":"10.3857/roj.2020.00710","DOIUrl":"10.3857/roj.2020.00710","url":null,"abstract":"<p><p>The coronavirus disease 2019 (COVID-19) pandemic has profoundly impacted cancer care, research and residency training in oncology worldwide. Many countries canceled exams, shortened their residency program and medical school tenure. Traditional teaching and learning method has faced significant disruption during this time and the situation has pushed us to adapt to e-learning. Most national and international cancer meetings were converted into a virtual platform during this time. E-learning ensures a safe environment to maintain education during a pandemic. Digital technology-based learning is likely to be used effectively in oncology training even after the pandemic ends. Stakeholders should work towards standardizing e-learning into routine educational modules and create a system of credibility and accountability.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/39/e2/roj-2020-00710.PMC8024185.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25539542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tamizh Selvan Gnana Sekaran, Vishakh R Kedilaya, Suchetha N Kumari, Praveenkumar Shetty, Pavan Gollapalli
{"title":"Exploring the differentially expressed genes in human lymphocytes upon response to ionizing radiation: a network biology approach.","authors":"Tamizh Selvan Gnana Sekaran, Vishakh R Kedilaya, Suchetha N Kumari, Praveenkumar Shetty, Pavan Gollapalli","doi":"10.3857/roj.2021.00045","DOIUrl":"https://doi.org/10.3857/roj.2021.00045","url":null,"abstract":"<p><strong>Purpose: </strong>The integration of large-scale gene data and their functional analysis needs the effective application of various computational tools. Here we attempted to unravel the biological processes and cellular pathways in response to ionizing radiation using a systems biology approach.</p><p><strong>Materials and methods: </strong>Analysis of gene ontology shows that 80, 42, 25, and 35 genes have roles in the biological process, molecular function, the cellular process, and immune system pathways, respectively. Therefore, our study emphasizes gene/protein network analysis on various differentially expressed genes (DEGs) to reveal the interactions between those proteins and their functional contribution upon radiation exposure.</p><p><strong>Results: </strong>A gene/protein interaction network was constructed, which comprises 79 interactors with 718 interactions and TP53, MAPK8, MAPK1, CASP3, MAPK14, ATM, NOTCH1, VEGFA, SIRT1, and PRKDC are the top 10 proteins in the network with high betweenness centrality values. Further, molecular complex detection was used to cluster these associated partners in the network, which produced three effective clusters based on the Molecular Complex Detection (MCODE) score. Interestingly, we found a high functional similarity from the associated genes/proteins in the network with known radiation response genes.</p><p><strong>Conclusion: </strong>This network-based approach on DEGs of human lymphocytes upon response to ionizing radiation provides clues for an opportunity to improve therapeutic efficacy.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/63/82/roj-2021-00045.PMC8024183.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A randomized prospective study comparing acute toxicity, compliance and objective response rate between simultaneous integrated boost and sequential intensity-modulated radiotherapy for locally advanced head and neck cancer.","authors":"Akanksha Grover, Tej Prakash Soni, Nidhi Patni, Dinesh Kumar Singh, Naresh Jakhotia, Anil Kumar Gupta, Lalit Mohan Sharma, Shantanu Sharma, Ravindra Singh Gothwal","doi":"10.3857/roj.2020.01018","DOIUrl":"10.3857/roj.2020.01018","url":null,"abstract":"<p><strong>Purpose: </strong>Intensity-modulated radiotherapy (IMRT) provides higher dose to target volumes and limits the dose to normal tissues. IMRT may be applied using either simultaneous integrated boost (SIB-IMRT) or sequential boost (SEQ-IMRT) technique. The objectives of this study were to compare acute toxicity and objective response rates between SIB-IMRT and SEQ-IMRT in patients with locally advanced head and neck cancer.</p><p><strong>Materials and methods: </strong>Total 110 patients with locally advanced carcinoma of oropharynx, hypopharynx, and larynx were randomized equally into the two arms (SIB-IMRT vs. SEQ-IMRT). Patients in SIB-IMRT arm received dose of 66 Gy in 30 fractions, 5 days a week, over 6 weeks. SEQ-IMRT arm's patients received 70 Gy in 35 fractions over 7 weeks. Weekly concurrent cisplatin chemotherapy was given in both arms. Patients were assessed for acute toxicities during the treatment and for objective response at 3 months after the radiotherapy.</p><p><strong>Results: </strong>Grade 3 dysphagia was significantly more with SIB-IMRT compared to SEQ-IMRT (72% vs. 41.2%; p = 0.006) but other toxicities including mucositis, dermatitis, xerostomia, weight-loss, incidence of nasogastric tube intubation and hospitalization for supportive management were similar in both the arms. Patients in SIB-IMRT arm showed better treatment-compliance and had significantly less treatment-interruption compared to SEQ-IMRT arm (p = 0.028). Objective response rates were similar in both the arms (p = 0.783).</p><p><strong>Conclusion: </strong>Concurrent chemoradiation with SIB-IMRT for locally advanced head and neck cancer is well-tolerated and results in better treatment-compliance, similar objective response rates, comparable incidence of mucositis and higher incidence of grade 3 dysphagia compared to SEQ-IMRT.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/d9/cf/roj-2020-01018.PMC8024186.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Salvage proton beam therapy for locoregional recurrence of non-small cell lung cancer.","authors":"Hyunju Shin, Jae Myoung Noh, Hongryull Pyo, Yong Chan Ahn, Dongryul Oh","doi":"10.3857/roj.2020.01074","DOIUrl":"https://doi.org/10.3857/roj.2020.01074","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to evaluate the clinical outcomes and toxicities of salvage proton beam therapy (PBT) in patients with locoregional recurrent non-small cell lung cancer (NSCLC).</p><p><strong>Materials and methods: </strong>We retrospectively reviewed 53 patients who received salvage PBT for locoregionally recurrent NSCLC between January 2016 and December 2019. The median clinical target volume (CTV) was 71.2 cm3 (range, 13.3 to 1,200.7 cm3). The median prescribed dose was 64.0 cobalt gray equivalent (CGE) (range, 45.0 to 70.0 CGE). One-third of the patients (32.1%) received concurrent chemoradiotherapy (CCRT).</p><p><strong>Results: </strong>The patients' median age was 67 years (range, 44 to 86 years). The initial treatments were surgery in 31 (58.5%), definitive CCRT in 12 (22.6%), and definitive radiotherapy in 10 (18.9%) patients. The median disease-free interval (DFI) was 14 months (range, 3 to 112 months). Thirty-seven patients (69.8%) had a previous radiotherapy history. Among them, 18 patients (48.7%) had in-field recurrence. The median follow-up time after salvage PBT was 15.0 months (range, 3.5 to 49.3 months). During the follow-up period, 26 patients (49.1%) experienced disease progression: local in 13 (24.5%), regional in 14 (26.5%), and distant metastases in 15 (26.5%). The 2-year overall survival (OS) rate, local control rate, and progression-free survival rate were 79.2%, 68.2%, and 37.1%, respectively. Shorter DFI (≤12 months; p = 0.015) and larger CTV (>80 mL; p = 0.014) were associated with poor OS. Grade 3 toxicities occurred in 8 patients (15.1%): esophagitis in 2, dermatitis in 3, and pulmonary toxicities in 4.</p><p><strong>Conclusion: </strong>Salvage PBT for locoregionally recurrent NSCLC was effective, and treatment-related toxicities were tolerable.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/7e/8b/roj-2020-01074.PMC8024187.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Atlas of sentinel lymph nodes in early breast cancer using single-photon emission computed tomography: implication for lymphatic contouring.","authors":"Sergey Nikolaevich Novikov, Pavel Ivanovich Krzhivitskii, Yulia Sergeevna Melnik, Alina Albertovna Valitova, Zhanna Viktorovna Bryantseva, Irina Alexandrovna Akulova, Sergey Vasilevich Kanaev","doi":"10.3857/roj.2020.00871","DOIUrl":"https://doi.org/10.3857/roj.2020.00871","url":null,"abstract":"<p><strong>Purpose: </strong>to determine the localization of sentinel lymph nodes (SLNs) in a large cohort of patients with breast cancer and validate the European Society for Therapeutic Radiology and Oncology (ESTRO), Radiation Therapy Oncology Group (RTOG), and Radiotherapy Comparative Effectiveness (RADCOMP) guidelines on regional lymph node clinical target volume (CTV-LN) delineation.</p><p><strong>Materials and methods: </strong>A total of 254 women with cT1-3N0-1M0 breast cancer underwent single-photon emission computed tomography (SPECT-CT) visualization of SLNs after intra- and peritumoral injection of 99mTc-radiocolloids. All SPECT-CT images were fused with reference simulation computed tomography. A 3D atlas of SLNs was created and used for evaluation of CTV-LN defined by contouring guidelines.</p><p><strong>Results: </strong>SPECT-CT visualized 532 SLNs that were localized in axillary level I in 67.5%, level II in 15.4%, level III in 7.3%, internal mammary in 8.5%, and supraclavicular in 1.3% cases. The majority of level II-IV and internal mammary SLNs were inside the recommended CTV-LN. Axillary level I SLNs were covered by ESTRO and RTOG contours in 85% and 85% cases, respectively. \"Out of contours\" SLNs were mostly detected in lateral subgroup of level I LN (18.5%), while 98%-99% of anterior pectoral and central axillary SLNs were covered by CTV-LN. Internal mammary SLNs were visualized in 33 cases and were outside ESTRO and RTOG contours in 3 and 6 observations, respectively.</p><p><strong>Conclusion: </strong>SPECT-CT atlas of SLNs demonstrated that in most cases ESTRO and RTOG guidelines correctly represented CTV-LNs with the exception of lateral subgroup of SLNs.</p>","PeriodicalId":46572,"journal":{"name":"Radiation Oncology Journal","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/26/ce/roj-2020-00871.PMC8024181.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25554237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}