Assessment of Eligibility and Utilization of Accelerated Partial Breast Irradiation in Korean Breast Cancer Patients (KROG 22-15) / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We investigated the proportions of patients eligible for accelerated partial breast irradiation (APBI) among those with pT1-2N0 breast cancer, based on the criteria set by the American Society for Radiation Oncology (ASTRO), the Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology (GEC-ESTRO), the American Brachytherapy Society (ABS), and the American Society of Breast Surgeons (ASBS). Additionally, we analyzed the rate of APBI utilization among eligible patients. @*Materials and Methods@#Patients diagnosed with pT1-2N0 breast cancer in 2019 were accrued in four tertiary medical centers in Korea. All patients had undergone breast conserving surgery followed by radiotherapy, either whole breast irradiation or APBI. To determine which guideline best predicts the use of APBI in Korea, the F1 score and Matthews Correlation Coefficient (MCC) were determined for each guideline. @*Results@#A total of 1,251 patients were analyzed, of whom 196 (15.7%) underwent APBI. The percentages of eligible patients identified by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria were 13.7%, 21.0%, 50.5%, and 63.5%, respectively. APBI was used to treat 54.4%, 37.2%, 27.1%, and 23.7% of patients eligible by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria, respectively. The ASTRO guideline exhibited the highest F1 score (0.76) and MCC (0.67), thus showing the best prediction of APBI utilization in Korea. @*Conclusion@#The proportion of Korean breast cancer patients who are candidates for APBI is substantial. The actual rate of APBI utilization among eligible patients may suggest there is a room for risk-stratified optimization in offering radiation therapy.

Survival and Functional Outcome after Treatment for Primary Base of Tongue Cancer: A Comparison of Definitive Chemoradiotherapy versus Surgery Followed by Adjuvant Radiotherapy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to compare the clinical and functional outcomes in patients with primary base of tongue (BOT) cancer who received definitive radiotherapy (RT) or surgery followed by radiotherapy (SRT). MATERIALS AND METHODS: Between January 2002 and December 2016, 102 patients with stage I-IVB primary BOT cancer underwent either definitive RT (n=46) or SRT (n=56), and treatment outcomes were compared between two groups. The expression of p16 was also analyzed. RESULTS: The RT group had more patients with advanced T stage (T3-4) disease (58.7% vs. 35.7%, p=0.021) and who received chemotherapy (91.3% vs. 37.5%, p < 0.001) than the SRT group. At a median follow up of 36.9 months (range, 3.3 to 181.5 months), the 5-year overall survival (OS) and disease-free survival (DFS) were 75.5% and 68.7%, respectively. With respect to treatment group, the 5-year OS and DFS in the RT and SRT groups did not differ significantly (OS, 68.7% vs. 80.5%, p=0.601; DFS, 63.1% vs. 73.1%, p=0.653). In multivariate analysis, OS differed significantly according to p16 expression (p16-negative vs. p16-positive; hazard ratio [HR], 0.145; 95% confidence interval [CI], 0.025 to 0.853; p=0.033). Regarding DFS, p16 expression (p16-negative vs. p16-positive; HR, 0.164; 95% CI, 0.045 to 0.598; p=0.006) showed a significant effect in multivariate analysis. Functional defects (late grade ≥ 3 dysphagia or voice alteration) were more frequently reported in the SRT than in the RT group (16.1% vs. 2.2%, p=0.021). CONCLUSION: Despite advanced disease, patients in the RT group showed comparable survival outcomes and better functional preservation than those in the SRT group.

Plasma Cell-Free DNA as a Predictive Marker after Radiotherapy for Hepatocellular Carcinoma

PURPOSE: Cell-free DNA (cfDNA) is gaining attention as a novel biomarker for oncologic outcomes. We investigated the clinical significance of cfDNA in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT). MATERIALS AND METHODS: Fifty-five patients with HCC who received RT were recruited from two prospective study cohorts: one cohort of 34 patients who underwent conventionally fractionated RT and a second of 21 patients treated with stereotactic body radiation therapy. cfDNA was extracted and quantified. RESULTS: In total, 30% of the patients had multiple tumors, 77% had tumors >2 cm, and 32% had portal vein tumor thrombus. Optimal cut-off values for cfDNA levels (33.65 ng/mL and 37.25 ng/mL, before and after RT) were used to divide patients into low-DNA (LDNA) and high-DNA (HDNA) groups. The pre-RT HDNA group tended to have more advanced disease and larger tumors (p=0.049 and p=0.017, respectively). Tumor response, intrahepatic failure-free rates, and local control (LC) rates were significantly better in the post-RT LDNA group (p=0.017, p=0.035, and p=0.006, respectively). CONCLUSION: Quantitative analysis of cfDNA was feasible in our cohorts. Post-RT cfDNA levels were negatively correlated with treatment outcomes, indicating the potential for the use of post-RT cfDNA levels as an early predictor of treatment responses and LC after RT for HCC patients.

Treatment outcome of radiation therapy and concurrent targeted molecular therapy in spinal metastasis from renal cell carcinoma

PURPOSE: To evaluate the clinical outcomes of patients who underwent radiation therapy with or without targeted molecular therapy for the treatment of spinal metastasis from renal cell carcinoma (RCC). MATERIALS AND METHODS: A total of 28 spinal metastatic lesions from RCC patients treated with radiotherapy between June 2009 and June 2015 were retrospectively reviewed. Thirteen lesions were treated concurrently with targeted molecular therapy (concurrent group) and 15 lesions were not (nonconcurrent group). Local control was defined as lack of radiographically evident local progression and neurological deterioration. RESULTS: At a median follow-up of 11 months (range, 2 to 58 months), the 1-year local progression-free rate (LPFR) was 67.0%. The patients with concurrent targeted molecular therapy showed significantly higher LPFR than those without (p = 0.019). After multivariate analysis, use of concurrent targeted molecular therapy showed a tendency towards improved LPFR (hazard ratio, 0.13; 95% confidence interval, 0.01 to 1.16). There was no difference in the incidence of systemic progression between concurrent and nonconcurrent groups. No grade ≥2 toxicities were observed during or after radiotherapy. CONCLUSION: Our study suggests the possibility that concurrent use of targeted molecular therapy during radiotherapy may improve LPFR. Further study with a large population is required to confirm these results.