Seo Hee Choi

Volumetric analysis of the substantia innominata in patients with Parkinson's disease according to cognitive status

The cholinergic system arising from the substantia innominata (SI) of the basal forebrain has an important role in the cognitive functions of Parkinsons disease (PD). We performed magnetic resonance imaging based volumetric analysis to evaluate the SI volume in patients with PD-intact cognition (PD-IC), PD-mild cognitive impairment (PD-MCI), and PD dementia (PDD). The mean normalized SI volume was significantly decreased in patients with PD-IC (1.54 ± 0.12, p < 0.001), PD-MCI (1.49 ± 0.12, p < 0.001), and PDD (1.39 ± 0.12, p < 0.001) compared with that of control subjects (1.68 ± 0.11). The normalized SI volume did not differ between patients with PD-IC and PD-MCI; however, the normalized SI volume was significantly decreased in patients with PDD compared with that in those with PD-IC (p < 0.001) or PD-MCI (p = 0.016). The normalized SI volume was significantly correlated with general cognitive status (r = 0.51, p < 0.001) as well as with performance in each cognitive subdomain, with a particularly significant independent association with attention (β = 0.33, p = 0.003) and object naming (β = 0.26, p = 0.017). The present study demonstrated that the SI volume in PD differs depending on cognitive status and is significantly correlated with cognitive performance.

Clinical Usefulness of 18F-Fluorodeoxyglucose-Positron Emission Tomography in Patients With Locally Advanced Pancreatic Cancer Planned to Undergo Concurrent Chemoradiation Therapy

PURPOSE To assess the role of coregistered (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting radiographically occult distant metastasis (DM) at staging in patients with locally advanced pancreatic cancer (LAPC) and to study whether FDG-PET parameters can predict relatively long-term survival in patients who are more likely to benefit from chemoradiation therapy (CRT). METHODS AND MATERIALS From our institutional database, we identified 388 LAPC patients with M0 on conventional computed tomography (CT) who were planned to undergo CRT. Coregistered FDG-PET staging was offered to all patients, and follow-up FDG-PET was used at the clinical discretion of the physician. RESULTS FDG-PET detected unsuspected CT-occult DM in 33% of all 388 patients and allowed them to receive systemic therapy immediately. The remaining 260 patients (PET-M0) underwent CRT selectively as an initial treatment. Early DM arose in 13.1% of 260 patients, and the 1-year estimated locoregional recurrence rate was 5.4%. Median overall survival (OS) and progression-free survival (PFS) were 14.6 and 9.3 months, respectively, at a median follow-up time of 32.3 months (range, 10-99.1 months). Patients with a baseline standardized uptake value (SUV) <3.5 and/or SUV decline ≥60% had significantly better OS and PFS than those having none, even after adjustment for all potential confounding variables (all P<.001). CONCLUSIONS FDG-PET can detect radiographically occult DM at staging in one-third of patients and spare them from the potentially toxic therapy. Additionally, FDG-PET parameters including baseline SUV and SUV changes may serve as useful clinical markers for predicting the prognosis in LAPC patients.

Postoperative radiotherapy in salivary ductal carcinoma: a single institution experience.

Purpose We reviewed treatment outcomes and prognostic factors for patients with salivary ductal carcinoma (SDC) treated with surgery and postoperative radiotherapy from 2005 to 2012. Materials and Methods A total of 16 patients were identified and 15 eligible patients were included in analysis. Median age was 61 years (range, 40 to 71 years) and 12 patients (80%) were men. Twelve patients (80%) had a tumor in the parotid gland, 9 (60%) had T3 or T4 disease, and 9 (60%) had positive nodal disease. All patients underwent surgery and postoperative radiotherapy. Postoperative radiotherapy was delivered using 3-dimensional conformal radiotherapy or intensity-modulated radiotherapy. Locoregional failure-free survival (LRFFS), distant failure-free survival (DFFS), progression-free survival (PFS), and overall survival (OS) were calculated using the Kaplan-Meier method. Differences in survival based on risk factors were tested using a log-rank test. Results Median total radiotherapy dose was 60 Gy (range, 52.5 to 63.6 Gy). Four patients received concurrent weekly chemotherapy with cisplatin. Among 10 patients who underwent surgery with neck dissection, 7 received modified radical neck dissection. With a median follow-up time of 38 months (range, 24 to 105 months), 4-year rates were 86% for LRFFS, 51% for DFFS, 46% for PFS, and 93% for OS. Local failure was observed in 2 patients (13%), and distant failure was observed in 7 (47%). The lung was the most common involved site of distant metastasis. Conclusion Surgery and postoperative radiotherapy in SDC patients resulted in good local control, but high distant metastasis remained a major challenge.

Clinical outcomes of adjuvant radiation therapy and prognostic factors in early stage uterine cervical cancer

Purpose To evaluate the outcomes of adjuvant radiotherapy (RT) and to analyze prognostic factors of survival in the International Federation of Gynecology and Obstetrics (FIGO) IB-IIA uterine cervical cancer. Materials and Methods We retrospectively reviewed the medical records of 148 patients with FIGO IB-IIA uterine cervical cancer who underwent surgery followed by adjuvant RT at the Yonsei Cancer Center between June 1997 and December 2011. Adjuvant radiotherapy was delivered to the whole pelvis or an extended field with or without brachytherapy. Among all patients, 57 (38.5%) received adjuvant chemotherapy either concurrently or sequentially. To analyze prognostic factors, we assessed clinicopathologic variables and metabolic parameters measured on preoperative 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). To evaluate the predictive performance of metabolic parameters, receiver operating characteristic curve analysis was used. Overall survival (OS) and disease-free survival (DFS) were analyzed by the Kaplan-Meier method. Results The median follow-up period was 63.2 months (range, 2.7 to 206.8 months). Locoregional recurrence alone occurred in 6 patients, while distant metastasis was present in 16 patients, including 2 patients with simultaneous regional failure. The 5-year and 10-year OSs were 87.0% and 85.4%, respectively. The 5-year and 10-year DFSs were 83.8% and 82.5%, respectively. In multivariate analysis, pathologic type and tumor size were shown to be significant prognostic factors associated with both DFS and OS. In subset analysis of 40 patients who underwent preoperative PET/CT, total lesion glycolysis was shown to be the most significant prognostic factor among the clinicopathologic variables and metabolic parameters for DFS. Conclusion Our results demonstrated that adjuvant RT following hysterectomy effectively improves local control. From the subset analysis of preoperative PET/CT, we can consider that metabolic parameters may hold prognostic significance in early uterine cervical cancer patients. More effective systemic treatments might be needed to reduce distant metastasis in these patients.

FDG‐PET predicts outcomes of treated bone metastasis following palliative radiotherapy in patients with hepatocellular carcinoma

To determine the utility of FDG‐PET in predicting long‐term infield tumour control after RT in patients with metastatic hepatocellular carcinoma (HCC) to bone.

Impact of Including Peritumoral Edema in Radiotherapy Target Volume on Patterns of Failure in Glioblastoma following Temozolomide-based Chemoradiotherapy

We assessed the impact of including peritumoral edema in radiotherapy volumes on recurrence patterns among glioblastoma multiforme (GBM) patients treated with standard chemoradiotherapy (CRT). We analyzed 167 patients with histologically confirmed GBM who received temozolomide (TMZ)-based CRT between May 2006 and November 2012. The study cohort was divided into edema (+) (n = 130) and edema (−) (n = 37) groups, according to whether the entire peritumoral edema was included. At a median follow-up of 20 months (range, 2–99 months), 118 patients (71%) experienced progression/recurrence (infield: 69%; marginal: 26%; outfield: 16%; CSF seeding: 12%). The median overall survival and progression-free survival were 20 months and 15 months, respectively. The marginal failure rate was significantly greater in the edema (−) group (37% vs. 22%, p = 0.050). Among 33 patients who had a favorable prognosis (total resection and MGMT-methylation), the difference in the marginal failure rates was increased (40% vs. 14%, p = 0.138). Meanwhile, treatment of edema did not significantly increase the incidence of pseudoprogression/radiation necrosis (edema (−) 49% vs. (+) 37%, p = 0.253). Inclusion of peritumoral edema in the radiotherapy volume can reduce marginal failures following TMZ-based CRT without increasing pseudoprogression/radiation necrosis.

Strategic Application of Radiotherapy for Hepatocellular Carcinoma

With increasing clinical use, radiotherapy (RT) has been considered reliable and effective method for hepatocellular carcinoma (HCC) treatment, depending on extent of disease and patient characteristics. RT for HCC can improve therapeutic outcomes through excellent local control, downstaging, conversion from unresectable to resectable status, and treatments of unresectable HCCs with vessel invasion or multiple intrahepatic metastases. In addition, further development of modern RT technologies, including image-guided radiotherapy (IGRT), intensity-modulated radiotherapy (IMRT), and stereotactic body radiotherapy, has expanded the indication of RT. An essential feature of IGRT is that it allows image guidance therapy through in-room images obtained during radiation delivery. Compared with 3D-conformal RT, distinctions of IMRT are inverse treatment planning process and use of a large number of treatment fields or subfields, which provide high precision and exquisitely conformal dose distribution. These modern RT techniques allow more precise treatment by reducing inter- and intra-fractional errors resulting from daily changes and irradiated dose at surrounding normal tissues. More recently, particle therapy has been actively investigated to improve effectiveness of RT. This review discusses modern RT strategies for HCC, as well as optimal selection of RT in multimodal approach for HCC.

Locoregional Treatment of the Primary Tumor in Patients With De Novo Stage IV Breast Cancer: A Radiation Oncologist's Perspective

Background: The aim of this study was to assess the outcomes of patients with de novo stage IV breast cancer after locoregional treatment (LRT) of primary site. Patients and Methods: We studied 245 patients diagnosed with de novo stage IV breast cancer. LRT of the primary tumor (+ systemic therapy) was performed in 82 (34%) patients (surgery, 27; surgery + radiotherapy (RT), 46; and RT, 9). Among those undergoing surgery, 64 (88%) patients underwent mastectomy, and 9 (12%) patients underwent breast‐conserving surgery (BCS). Local recurrence‐free survival (LRFS) and overall survival (OS) were investigated, and propensity score matching was used to balance patient distributions. Results: The 5‐year LRFS and OS rates were 27% and 50%, respectively. Advanced T stage (T4), liver or brain metastasis, ≥ 5 metastatic sites, and absence of hormone therapy were significant adverse factors for LRFS, whereas T4 stage and absence of hormone therapy were significant for OS. The LRT group demonstrated significantly more favorable outcomes (5‐year LRFS, 61%; 5‐year OS, 71%), especially after surgery. After matching, survival rates remained significantly higher for patients who received LRT (5‐year LRFS, 62% vs. 20%; P < .001; 5‐year OS, 73% vs. 45%; P = .02). BCS + RT was superior to mastectomy ± RT, which can be attributed to more patients with a low tumor burden undergoing BCS + RT. Outcomes were better with post‐mastectomy RT in selected patients (≥ N2, ≥ T3, or T2N1). Conclusions: Upfront LRT including RT is an important option together with systemic therapies for de novo stage IV breast cancer.

Treatment outcome and prognostic molecular markers of supratentorial primitive neuroectodermal tumors

Background To identify prognostic factors and define the optimal management of patients with supratentorial primitive neuroectodermal tumors (sPNETs), we investigated treatment outcomes and explored the prognostic value of specific molecular markers. Methods A total of 47 consecutive patients with pathologically confirmed sPNETs between May 1985 and June 2012 were included. Immunohistochemical analysis of LIN28, OLIG2, and Rad51 expression was performed and correlated with clinical outcome. Results With a median follow-up of 70 months, 5-year overall survival (OS) and progression-free survival (PFS) was 55.5% and 40%, respectively, for all patients. Age, surgical extent, and radiotherapy were significant prognostic factors for OS and PFS. Patients who received initially planned multimodal treatment without interruption (i.e., radiotherapy and surgery (≥subtotal resection), with or without chemotherapy) showed significantly higher 5-year OS (71.2%) and PFS (63.1%). In 29 patients with available tumor specimens, tumors with high expression of either LIN28 or OLIG2 or elevated level of Rad51 were significantly associated with poorer prognosis. Conclusions We found that multimodal treatment improved outcomes for sPNET patients, especially when radiotherapy and ≥subtotal resection were part of the treatment regimen. Furthermore, we confirmed the prognostic significance of LIN28 and OLIG2 and revealed the potential role of Rad51 in sPNETs.

Reduced pelvic field sparing anastomosis for postoperative radiotherapy in selected patients with mid–upper rectal cancer

Abstract The aim of this study was to report the clinical results of reduced pelvic field radiotherapy (RT), excluding the anastomotic site, after total mesorectal excision in selected patients with rectal cancer. Between 2011 and 2014, 99 patients underwent upfront surgery for clinically less-advanced tumors but were finally diagnosed as pT3/N+. Among them, 50 patients with mid–upper rectal cancer who received postoperative RT with a reduced pelvic field were included in this retrospective review. This group was composed of patients with high seated tumors, complete resection with a clear circumferential resection margin, and no complication during surgery. We investigated treatment outcomes, toxicity and the effect of RT-field reduction on organs-at risk in 5 randomly selected patients. During the median follow-up period of 42 months (range: 15−59 months), tumors recurred in 9 patients (18%). The 3-year overall and disease-free survival were 98% and 81%, respectively. Distant metastasis was the dominant failure pattern (n = 8, 16%), while no recurrences occurred at or near anastomotic sites. No anastomotic complications were found on pelvic examination, images and/or colonoscopy. Reported acute and late RT-related toxicities were mostly mild to moderate, with only small numbers of Grade 3 toxicities. None of the patients developed Grade 4−5 acute or late toxicity. With a caudally reduced field, 64% reduction in absolute anastomotic exposure at the maximum dose was achieved compared with the traditional whole-pelvic field (P = 0.008). The reduced pelvic field RT was able to minimize late anastomotic complication without increasing its recurrence in selected patients with mid–upper rectal cancer in the postoperative setting.