Central Nervous System Failure in Korean Breast Cancer Patients with HER2-Enriched Subtype: Korean Radiation Oncology Group 16-15 Multicenter Retrospective Study / 한국유방암학회지

PURPOSE: The purpose of this study was to evaluate the risk of central nervous system (CNS) failure in Korean patients with human epidermal growth factor receptor 2 (HER2)-enriched breast cancer treated with surgery followed by postoperative radiotherapy (RT). METHODS: A total of 749 patients from eight institutions were enrolled in this study. All of them underwent surgery followed by postoperative RT from 2003 to 2011; 246 (32.8%) received neoadjuvant chemotherapy and 649 (81.7%) received adjuvant chemotherapy. Adjuvant trastuzumab was administered to 386 patients (48.6%). RESULTS: The median follow-up duration was 84 (range, 8–171) months. The 7-year disease-free and overall survival rates were 79.0% and 84.2%, respectively. On multivariate analysis, mastectomy, nodal involvement, and presence of lymphatic invasion were correlated with poor overall survival (p = 0.004, 0.022, and 0.011, respectively), whereas T stage and lymphatic invasion were associated with disease-free survival (p = 0.018 and 0.005, respectively). Regarding CNS failures, 30 brain metastases, 2 leptomeningeal metastases, and 8 brain and leptomeningeal metastases were noted. The 7-year CNS relapse-free survival rates in patients receiving and not receiving trastuzumab were 91.2% and 96.9%, respectively (p = 0.005). On multivariate analysis, the administration of adjuvant trastuzumab was the only prognostic factor in predicting a higher CNS failure rate (hazard ratio, 2.260; 95% confidence interval, 1.076–4.746; p = 0.031). CONCLUSION: Adjuvant trastuzumab was associated with higher CNS failure rate in Korean patients with HER2-enriched breast cancer. Close monitoring and reasonable approaches such as CNS penetrating HER2 blockades combined with the current standard therapy could contribute to improving intracranial tumor control and quality of life in patients with CNS metastasis from HER2-enriched breast cancer.

Risk Factors for Distant Metastasis as a Primary Site of Treatment Failure in Early-Stage Breast Cancer / 전남의대학술지

The aim of this study was to evaluate the risk factors for distant metastasis (DM) as a primary site of failure in early-stage breast cancer. Data from 294 patients diagnosed with pathologic stage I or II breast cancer between January 2000 and December 2005 were reviewed retrospectively. Median follow-up duration was 81.0 months (range, 18-135 months). The total number of patients with DM without evidence of locoregional recurrence was 20 and the median time between surgery and DM was 29 months (range, 9-79 months). Median survival time was 38 months (range, 22-77 months) after operation. HER-2 positivity (p=0.015), T stage of tumor (p=0.012), and number of involved lymph nodes (p=0.008) were significant predictors of DM in the univariable analysis. Number of involved lymph nodes [p=0.005, hazards ratio (HR): 1.741; 95% confidence interval (CI): 1.178-2.574] and HER-2 positivity (p=0.018, HR: 2.888; 95% CI: 1.201-6.941) had a statistically significant effect on DM-free survival in the multivariable analysis. A cautious evaluation may be helpful when patients with risk factors for DM have symptoms implying the possibility of DM. To reduce DM, applying intensive therapy is needed after curative surgery for patients with high risk for DM.

Risk Factors for Distant Metastasis as a Primary Site of Treatment Failure in Early-Stage Breast Cancer / 전남의대학술지

The aim of this study was to evaluate the risk factors for distant metastasis (DM) as a primary site of failure in early-stage breast cancer. Data from 294 patients diagnosed with pathologic stage I or II breast cancer between January 2000 and December 2005 were reviewed retrospectively. Median follow-up duration was 81.0 months (range, 18-135 months). The total number of patients with DM without evidence of locoregional recurrence was 20 and the median time between surgery and DM was 29 months (range, 9-79 months). Median survival time was 38 months (range, 22-77 months) after operation. HER-2 positivity (p=0.015), T stage of tumor (p=0.012), and number of involved lymph nodes (p=0.008) were significant predictors of DM in the univariable analysis. Number of involved lymph nodes [p=0.005, hazards ratio (HR): 1.741; 95% confidence interval (CI): 1.178-2.574] and HER-2 positivity (p=0.018, HR: 2.888; 95% CI: 1.201-6.941) had a statistically significant effect on DM-free survival in the multivariable analysis. A cautious evaluation may be helpful when patients with risk factors for DM have symptoms implying the possibility of DM. To reduce DM, applying intensive therapy is needed after curative surgery for patients with high risk for DM.

Permanent Brachytherapy of Localized Prostate Cancer: Preliminary Results / 대한방사선종양학회지

PURPOSE: To evaluate the biochemical control rate and the rate of side effects after performing permanent brachytherapy of localized prostate cancer. MATERIALS AND METHODS: 67 patients with localized prostate cancer were treated with brachytherapy between April 2007 and December 2008. Of these, 43 patients who were followed up and did not receive external radiotherapy were evaluated for the change in prostate specific antigen (PSA) level and the occurrence of side effects. In total, 18 patients were classified as low risk, 19 patients as intermediate risk, and 6 patients as high risk. The prescription dose was 145 Gy. RESULTS: A PSA increase greater than 2 ng/mL occurred in 2 patients (4.7%). Radiation Therapy Oncology Group (RTOG) grade 1 and 2 acute urologic complications (UC) occurred in 40 and 3 patients, respectively. Further, 5 patients had RTOG grade 1 acute rectal complication (RC). The numbers of RTOG grade 1, 2, and 3 chronic UC were 1, 4, and 1, respectively. The numbers of RTOG grade 1, 2, and 4 chronic RC were 5, 10, and 3, respectively. The statistically significant risk factors (RF) of acute RC were the minimal dose in the most irradiated 0.1 cc volume (D0.1CC, p=0.041) and absolute volume receiving 150% of the prescribed dose (V150cc, p=0.038) in the entire rectum (ER). The percentage (V100%, p=0.019) and absolute volume (V100cc, p=0.047) in the involved rectum (IR) were also statistically significant. The RF of chronic RC were V100% (p=0.011) in the ER and the D0.1cc (p=0.049), V100cc (p=0.023) in the IR. The number of used seeds were related with acute UC (p=0.028). CONCLUSION: Permanent brachytherpy of localized prostate cancer showed a favorable short term biochemical control rate. As such, selective intermediate and high risk patients can be managed with permanent brachytherapy. The effort to reduce rectal complication is also necessary.

A comparison of preplan MRI and preplan CT-based prostate volume with intraoperative ultrasound-based prostate volume in real-time permanent brachytherapy

PURPOSE: The present study compared the difference between intraoperative transrectal ultrasound (iTRUS)-based prostate volume and preplan computed tomography (CT), preplan magnetic resonance imaging (MRI)-based prostate volume to estimate the number of seeds needed for appropriate dose coverage in permanent brachytherapy for prostate cancer. MATERIALS AND METHODS: Between March 2007 and March 2011, among 112 patients who underwent permanent brachytherapy with 125I, 60 image scans of 56 patients who underwent preplan CT (pCT) or preplan MRI (pMRI) within 2 months before brachytherapy were retrospectively reviewed. Twenty-four cases among 30 cases with pCT and 26 cases among 30 cases with pMRI received neoadjuvant hormone therapy (NHT). In 34 cases, NHT started after acquisition of preplan image. The median duration of NHT after preplan image acquisition was 17 and 21 days for cases with pCT and pMRI, respectively. The prostate volume calculated by different modalities was compared. And retrospective planning with iTRUS image was performed to estimate the number of 125I seed required to obtain recommended dose distribution according to prostate volume. RESULTS: The mean difference in prostate volume was 9.05 mL between the pCT and iTRUS and 6.84 mL between the pMRI and iTRUS. The prostate volume was roughly overestimated by 1.36 times with pCT and by 1.33 times with pMRI. For 34 cases which received NHT after image acquisition, the prostate volume was roughly overestimated by 1.45 times with pCT and by 1.37 times with pMRI. A statistically significant difference was found between preplan image-based volume and iTRUS-based volume (p < 0.001). The median number of wasted seeds is approximately 13, when the pCT or pMRI volume was accepted without modification to assess the required number of seeds for brachytherapy. CONCLUSION: pCT-based volume and pMRI-based volume tended to overestimate prostate volume in comparison to iTRUS-based volume. To reduce wasted seeds and cost of the brachytherapy, we should take the volume discrepancy into account when we estimate the number of 125I seeds for permanent brachytherapy.

A Correction Method of Dose to Attenuation Rate of Transmitting Photon Beam Through Couch Top for Radiosurgery Using Novalis / 의학물리

This study has its own goal to deliver the accurate dose on the target volume by calculating and modifying the attenuation rate of photon beam transmitting the couch top with geometric model. The experiment was that the transmission rate and attenuation rate of photon beam transmitting the couch top was predicted by the geometric model, then compared and analyzed with what was measured experimentally based on that. The result showed that the predicted value by the geometric model accorded closely with the experimental value. In addition, in order to judge whether the practical clinical application is available, the point dose, measured after modifying the attenuation rate modelinged according to the treatment plan of a patient of spine radiosurgery, was compared with the one done nothing. The result was that the former showed decreased error range with treatment planned one than the latter. This papers calculated the transmission and attenuation rate with the geometric model transmitting the couch top and verified it experimentally. This method is expected to be very useful in not only the radiosurgery using Novalis but also the general radiation therapy.