Radiation Oncology Journal最新文献

Purpose: We aimed to determine whether low-dose radiotherapy (LDRT) is effective in patients with Alzheimer disease (AD).

Materials and methods: We included patients according to the following criteria: probable Alzheimer's dementia according to the New Diagnostic Criteria for Alzheimer's Disease; confirmation of amyloid plaque deposits on baseline amyloid positron emission tomography (PET); a Korean Mini-Mental State Examination 2nd edition (K-MMSE-2) score of 13-26; and a Global Clinical Dementia Rating (CDR) score of 0.5-2 points. LDRT was performed six times at 0.5 Gy each. Post-treatment cognitive function tests and PET-CT examinations were performed to evaluate efficacy. The medication for AD treatment was maintained throughout the study period.

Results: At 6 months after LDRT, neurological improvement was seen in 20% of patients. Patient #2 showed improvement in all domains of the Seoul Neuropsychological Screening Battery II (SNSB-II). Moreover, the K-MMSE-2 and Geriatric Depression Score-Short Form scores improved from 20 to 23 and from 8 to 2, respectively. For patient #3, the CDR score (sum of box score) improved from 1 (4.0) to 1 (3.5) at 3 months follow-up. Moreover, the Z scores for language and related functions, memory, and frontal executive function improved to -2.56, -1.86, and -1.32, respectively at the 6-month follow-up. Two patients complained of mild nausea and mild hair loss during LDRT, which improved after treatment.

Conclusion: One of the five patients with AD treated with LDRT experienced a temporary improvement in SNSB-II. LDRT is tolerable in patients with AD. We are currently under follow-up and will conduct cognitive function tests after 12 months after LDRT. A large-scale randomized controlled trial with a longer follow-up period is warranted to determine the effect of LDRT on patients with AD.

Purpose: This study aimed to evaluate the role of inflammatory blood markers in predicting the pathological response rate after neoadjuvant chemoradiation (neo-CRT) in patients with locally advanced rectal cancer (LARC).

Materials and methods: In this prospective cohort study, we analyzed the data of patients with LARC who underwent neo-CRT and surgical removal of the rectal mass between 2020 and 2022 in a tertiary medical center. Patients were examined weekly during chemoradiation and neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and systemic immune inflammation index (SII) were calculated from weekly laboratory data. Wilcoxon signed-ranks and logistic regression analysis were utilized to determine whether any laboratory parameters during different time point assessments or their relative changes could predict the tumor response based on a permanent pathology review.

Results: Thirty-four patients were recruited for the study. Eighteen patients (53%) achieved good pathologic response. Statistical analysis by Wilcoxon signed-ranks method indicated significant rises in NLR, PLR, MLR, and SII on weekly assessments during chemoradiation. Having an NLR over 3.21 during chemoradiation was correlated with the response on a Pearson chi-squared test (p = 0.04). Also, a significant correlation was found between the PLR ratio over 1.8 and the response (p = 0.02). NLR ratio over 1.82 marginally missed a significant correlation with the response (p = 0.13). On multivariate analysis, a PLR ratio over 1.8 showed a trend for response (odds ratio = 10.4; 95% confidence interval, 0.9-123; p = 0.06).

Conclusion: In this study, PLR ratio as an inflammatory marker showed a trend in the prediction of response in permanent pathology to neo-CRT.

Purpose: Studies about the effect of radiation therapy (RT) on immune cells are usually limited to a high-grade glioma mostly exposed to chemotherapy and a high dose of steroid which also could affect immune cells. The purpose of this retrospective analysis of low-grade brain tumor patients treated by RT alone is to determine significant factors influencing neutrophil-to-lymphocyte ratio (NLR), absolute neutrophil counts (ANC), and absolute lymphocyte counts (ALC).

Materials and methods: A total of 41 patients who received RT between 2007 and 2020 were analyzed. Patients who received chemotherapy and high-dose of steroid were excluded. ANC and ALC were collected before starting RT (baseline) and within one-week before ending RT (post-treatment). Changes of ANC, ALC, and NLR between baseline and post-treatment were calculated.

Results: ALC decreased in 32 patients (78.1%). NLR increased in 31 patients (75.6%). No patients developed grade 2 or higher hematologic toxicities. The decrease of ALC was significantly correlated with the dose to brain V15 in a simple and multiple linear regression (p = 0.043). Brain V10 and V20 adjacent to V15 were also marginally significant factors determining the reduction of lymphocytes (p = 0.050 and p = 0.059, respectively). However, it was difficult to find predictive factors affecting changes of ANC and NLR.

Conclusion: In low-grade brain tumor patients who are treated by RT alone, ALC decreased and NLR increased in three-fourth of patients, although the magnitude was minimal. The decrease of ALC was mainly affected by low dose to the brain. However, RT dose was not correlated with changes of ANC or NLR.

Purpose: We aimed to determine whether patients with esophageal cancer with a low baseline body mass index (BMI) have a poor prognosis following radiotherapy (RT).

Materials and methods: We retrospectively analyzed data from 50 patients with esophageal cancer to determine whether a low starting BMI (before RT) was associated with a poor outcome. All study participants were diagnosed with non-metastatic esophageal squamous cell carcinoma (SCC).

Results: The number of patients at each T stage were as follows: 7 (14%) patients at T1, 18 (36%) at T2, 19 (38%) at T3, and 6 (12%) at T4. Based on BMI, 7 (14%) patients were defined as underweight. A low BMI was common in patients with T3/T4 stage esophageal cancer (7/43, p = 0.01). Overall, the 3-year progression-free survival (PFS) and overall survival (OS) rates were 26.3% and 69.2%, respectively. In univariate analysis, clinical factors associated with poor PFS included being underweight (BMI <18.5 kg/m2; p = 0.011) and a positive N status (p = 0.017). Univariate analysis also revealed that being underweight was associated with a decrease in OS (p = 0.003). However, being underweight was not an independent prognostic factor for PFS and OS.

Conclusion: Patients with esophageal SCC with a low starting BMI (BMI <18.5 kg/m2) are more prone to have a negative survival outcome following RT than patients who are considered to be normal weight or overweight. For this reason, it is important that clinicians pay more attention to BMI when treating patients with esophageal SCC.

Purpose: The target delineation of whole ventricle radiotherapy (WVRT) in germinoma varies among radiation oncologists, especially regarding the inclusion of the prepontine cistern (PC). We evaluated the outcome of PC-sparing WVRT in localized germinoma.

Materials and methods: We identified 87 localized intracranial germinoma patients who received radiotherapy (RT) following chemotherapy between 1999 and 2020. By institutional policy, RT for localized germinoma excluded PC from the target volume. WVRT was delivered to 65 patients (74.7%) and involved field radiotherapy (IFRT) to 22 patients (25.3%). The median dose was 45.0 Gy (range, 23.4 to 55.8 Gy) for the primary tumor and 19.8 Gy (rangem 14.4 to 36.0 Gy) for the whole ventricle. We analyzed the dosimetric differences of the organs at risk between the PC-excluding plans and the PC-including ones.

Results: The median follow-up duration was 7.8 years (range, 1.0 to 22.5 years). The 10-year recurrence-free survival and overall survival rates were 86.3% and 90.9%, respectively. The recurrences occurred in eight patients (8.7%), including five patients after IFRT and three after WVRT. Five of them showed recurrences at lateral ventricles and only one patient experienced spinal cord relapse. However, no relapse in the PC occurred. Endoscopic third ventriculostomy was not a significant prognostic factor. The dosimetric comparisons showed significantly lower mean doses to the brainstem and the cochleae when the PC was excluded.

Conclusion: WVRT for localized germinoma can safely exclude the PC in the target volume, reducing radiation dose to the brain stem. The target protocol needs to reach a consensus regarding the PC in prospective trials.

Rectal resection surgery after neoadjuvant treatment has been the mainstay treatment of locally advanced rectal cancer. However, functional outcomes and quality of life after radical resection of the rectum remain suboptimal. The excellent oncologic outcomes in patients who achieved pathologic complete response after neoadjuvant treatment questioned the need for radical surgery. The watch-and-wait approach is a noninvasive therapeutic alternative for organ preservation and avoiding operative morbidity. In the watch-and-wait approach, patients with locally advanced rectal cancer who achieve excellent clinical response after neoadjuvant treatment undergo active surveillance rather than rectal cancer surgery. In this practical review, we summarized the main results of studies on the watch-and-wait approach and provided a practical method for implementing the watch-and-wait approach.

Purpose: This study explored the potential feasibility of cell-free DNA (cfDNA) in monitoring treatment response through the measurement of chromosomal instabilities using I-scores in the context of radiation therapy (RT) for other solid tumors.

Materials and methods: This study enrolled 23 patients treated with RT for lung, esophageal, and head and neck cancer. Serial cfDNA monitoring was performed before RT, 1 week after RT, and 1 month after RT. Low-depth whole-genome sequencing was done using Nano kit and NextSeq 500 (Illumina Inc.). To measure the extent of genome-wide copy number instability, I-score was calculated.

Results: Pretreatment I-score was elevated to more than 5.09 in 17 patients (73.9%). There was a significant positive correlation between the gross tumor volume and the baseline I-score (Spearman rho = 0.419, p = 0.047). The median I-scores at baseline, post-RT 1 week (P1W), and post-RT 1 month (P1M) were 5.27, 5.13, and 4.79, respectively. The I-score at P1M was significantly lower than that at baseline (p = 0.002), while the difference between baseline and P1W was not significant (p = 0.244).

Conclusion: We have shown the feasibility of cfDNA I-score to detect minimal residual disease after RT in patients with lung cancer, esophageal cancer, and head and neck cancer. Additional studies are ongoing to optimize the measurement and analysis of I-scores to predict the radiation response in cancer patients.

Purpose: There has been limited work assessing the use of re-irradiation (re-RT) for local failure following stereotactic spinal radiosurgery (SSRS). We reviewed our institutional experience of conventionally-fractionated external beam radiation (cEBRT) for salvage therapy following SSRS local failure.

Materials and methods: We performed a retrospective review of 54 patients that underwent salvage conventional re-RT at previously SSRS-treated sites. Local control following re-RT was defined as the absence of progression at the treated site as determined by magnetic resonance imaging.

Results: Competing risk analysis for local failure was performed using a Fine-Gray model. The median follow-up time was 25 months and median overall survival (OS) was 16 months (95% confidence interval [CI], 10.8-24.9 months) following cEBRT re-RT. Multivariable Cox proportional-hazards analysis revealed Karnofsky performance score prior to re-RT (hazard ratio [HR] = 0.95; 95% CI, 0.93-0.98; p = 0.003) and time to local failure (HR = 0.97; 95% CI, 0.94-1.00; p = 0.04) were associated with longer OS, while male sex (HR = 3.92; 95% CI, 1.64-9.33; p = 0.002) was associated with shorter OS. Local control at 12 months was 81% (95% CI, 69.3-94.0). Competing risk multivariable regression revealed radioresistant tumors (subhazard ratio [subHR] = 0.36; 95% CI, 0.15-0.90; p = 0.028) and epidural disease (subHR = 0.31; 95% CI, 0.12-0.78; p =0.013) were associated with increased risk of local failure. At 12 months, 91% of patients maintained ambulatory function.

Conclusion: Our data suggest that cEBRT following SSRS local failure can be used safely and effectively. Further investigation is needed into optimal patient selection for cEBRT in the retreatment setting.