Won Taek Kim

Measurement of tumor volume by PET to evaluate prognosis in patients with head and neck cancer treated by chemo-radiation therapy.

Abstract Purpose. To evaluate the prognostic value of the metabolic tumor volume measured on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and other clinical factors in patients treated for locally advanced head-and-neck cancer (HNC) at a single institution. Materials and methods. Between June 2005 and August 2008, 59 patients with HNC that underwent pretreatment FDG-PET studies received neoadjuvant chemotherapy and radiation therapy. Metabolically active tumor regions were delineated on the pretreatment PET scans by a fixed SUV of 2.5. We evaluated the relationship of the 18F-fluorodeoxyglucose-PET maximum standardized uptake value (SUV) and the metabolic tumor volume (MTV) with the progression-free survival (PFS) and overall survival (OS). Results. The MTV and lymph node metastasis were predictive of the PFS and OS. The lymph node status did not correlate with the MTV. A higher MTV of 9.3 cm3 was significantly associated with an increased risk of recurrence (2.19-fold, p = 0.006) and death (1.62-fold, p = 0.051). Separation of patients with tumor volumes ≤ 9.3 cm3 and no lymph node disease vs. any other combination was strongly predictive of the PFS and the OS. Conclusions. MTV and lymph node status were prognostic values associated with survival. Quantitative measurement of tumor volume separates patients with a good prognosis from those with a poorer prognosis. A subset of patients with relatively small tumors and no lymph node involvement did very well.

Inactivation of O6-methylguanine-DNA methyltransferase in soft tissue sarcomas: association with K-ras mutations

The DNA-repair protein O(6)-methylguanine-DNA methyltransferase removes alkyl adducts from the O(6)-position of guanine. The adducts can mispair with T during DNA replication, resulting in a G-to-A mutation. Epigenetic inactivation of O(6)-methylguanine-DNA methyltransferase has been found in human neoplasia and is considered one of the implicated factors in chemoresistance. Sixty-two patients with soft tissue sarcomas were analyzed with regard to the status of O(6)-methylguanine-DNA methyltransferase protein expression status using immunohistochemistry and promoter hypermethylation of the MGMT gene using methylation-specific PCR. G-to-A transitions in codons 12 and 13 of the K-ras oncogene were investigated using PCR and direct automated sequencing analysis. A loss of O(6)-methylguanine-DNA methyltransferase expression was noted in 20 (32.3%) cases of 62 total soft tissue sarcomas. The MGMT promoter hypermethylation rate was 33.9% (21/62 cases). Of the 54 sarcomas evaluated, K-ras mutations were found in only 2 (3.7%) cases. Loss of O(6)-methylguanine-DNA methyltransferase expression and MGMT promoter hypermethylation showed a significant association with high American Joint Committee on Cancer stage, high French Federation of Cancer Centers grade, and aggressive behavior. On multivariate analysis, these were not an independently significant prognostic factors. However, when the group receiving chemotherapy was analyzed (n = 27), loss of O(6)-methylguanine-DNA methyltransferase expression was correlated with worse survival on multivariate analysis (P = .024). MGMT promoter hypermethylation status had a strong correlation with loss of O(6)-methylguanine-DNA methyltransferase expression (P = .000). Our results suggest that MGMT promoter hypermethylation and loss of O(6)-methylguanine-DNA methyltransferase expression tend to be associated with poor prognosis and that the loss of O(6)-methylguanine-DNA methyltransferase protein expression frequently occurs via MGMT promoter hypermethylation. However, MGMT promoter hypermethylation was not significantly associated with point mutations of K-ras at codons 12 and 13 in sarcomas.

Short-course palliative radiotherapy for uterine cervical cancer.

Purpose The purpose of this retrospective study was to evaluate the efficacy and feasibility of short-course hypofractionated radiotherapy (RT) for the palliation of uterine cervical cancer. Materials and Methods Seventeen patients with cancer of the uterine cervix, who underwent palliative hypofractionated 3-dimensional conformal radiotherapy between January 2002 and June 2012, were retrospectively analyzed. RT was delivered to symptomatic lesions (both the primary mass and/or metastatic regional lymph nodes). The total dose was 20 to 25 Gy (median, 25 Gy) in 5 Gy daily fractions. Results The median follow-up duration was 12.2 months (range, 4 to 24 months). The median survival time was 7.8 months (range, 4 to 24 months). Vaginal bleeding was the most common presenting symptom followed by pelvic pain (9 patients). The overall response rates were 93.8% and 66.7% for vaginal bleeding control and pelvic pain, respectively. Nine patients did not have any acute side effects and 7 patients showed minor gastrointestinal toxicity. Only 1 patient had grade 3 diarrhea 1 week after completion of treatment, which was successfully treated conservatively. Late complications occurred in 4 patients; however, none of these were of grade 3 or higher severity. Conclusion Short-course hypofractionated RT was effective and well tolerated as palliative treatment for uterine cervical cancer.

Three-dimensional conformal radiotherapy for portal vein tumor thrombosis alone in advanced hepatocellular carcinoma

Purpose We sought to evaluate the clinical outcomes of 3-dimensional conformal radiation therapy (3D-CRT) for portal vein tumor thrombosis (PVTT) alone in patients with advanced hepatocellular carcinoma. Materials and Methods We retrospectively analyzed data on 46 patients who received 3D-CRT for PVTT alone between June 2002 and December 2011. Response was evaluated following the Response Evaluation Criteria in Solid Tumors. Prognostic factors and 1-year survival rates were compared between responders and non-responders. Results Thirty-seven patients (80.4%) had category B Child-Pugh scores. The Eastern Cooperative Oncology Group performance status score was 2 in 20 patients. Thirty patients (65.2%) had main or bilateral PVTT. The median irradiation dose was 50 Gy (range, 35 to 60 Gy) and the daily median dose was 2 Gy (range, 2.0 to 2.5 Gy). PVTT response was classified as complete response in 3 patients (6.5%), partial response in 12 (26.1%), stable disease in 19 (41.3%), and progressive disease in 12 (26.1%). There were 2 cases of grade 3 toxicities during or 3 months after radiotherapy. Twelve patients in the responder group (15 patients) received at least 50 Gy irradiation, but about 84% of patients in the non-responder group received less than 50 Gy. The 1-year survival rate was 66.8% in responders and 27.4% in non-responders constituting a statistically significant difference (p = 0.008). Conclusion Conformal radiotherapy for PVTT alone could be chosen as a palliative treatment modality in patients with unfavorable conditions (liver, patient, or tumor factors). However, more than 50 Gy of radiation may be required.

Analysis of the Prognostic Factors for Distant Metastasis after Induction Chemotherapy Followed by Concurrent Chemoradiotherapy for Head and Neck Cancer

Purpose The aim of this study is to identify the prognostic factors of distant metastasis (DM) after induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CRT) for locoregionally advanced head and neck cancer (HNC). Materials and Methods A total of 321 patients with HNC who underwent IC followed by CRT treated between January 2005 and December 2010 were analyzed retrospectively. IC consisted of three courses of docetaxel (70 mg/m2) and cisplatin (75 mg/m2) every three weeks, followed by radiotherapy of 66-70 Gy/2 Gy per fraction/5 fractions per week concurrent with weekly cisplatin (40 mg/m2). Tumor/nodal stage, primary site, tumor differentiation, lower neck node involvement (level IV, VB, and supraclavicular regions), number of concurrent chemotherapy cycles, overall duration of radiotherapy, and response to IC were assessed as potential prognostic factors influencing DM and survival outcome. Results The five-year loco-regional recurrence and DM rates were 23.6% and 18.2%. N stage, overall duration of radiotherapy, lower neck node involvement, and response to IC were significant factors for DM. With a median follow-up period of 52 months (range, 4 to 83 months), the 5-year progression-free, DM-free, and overall survival rates were 41.2%, 50.7%, and 55.1%, respectively. Lower neck node involvement (p=0.008) and poor response to IC (p < 0.001) showed an association with significantly inferior DM-free survival. Conclusion Even with the addition of IC, the DM rate and survival outcome were poor when metastatic lower neck lymph nodes were present or when patients failed to respond after receiving IC.

The Role of Neoadjuvant Chemotherapy in the Treatment of Nasopharyngeal Carcinoma: A Multi-institutional Retrospective Study (KROG 11-06) Using Propensity Score Matching Analysis

Purpose We compared the treatment results and toxicity in nasopharyngeal carcinoma (NPC) patients treated with concurrent chemotherapy (CCRT) alone (the CRT arm) or neoadjuvant chemotherapy followed by CCRT (the NCT arm). Materials and Methods A multi-institutional retrospective study was conducted to review NPC patterns of care and treatment outcome. Data of 568 NPC patients treated by CCRT alone or by neoadjuvant chemotherapy followed by CCRT were collected from 15 institutions. Patients in both treatment arms were matched using the propensity score matching method, and the clinical outcomes were analyzed. Results After matching, 300 patients (150 patients in each group) were selected for analysis. Higher 5-year locoregional failure-free survival was observed in the CRT arm (85% vs. 72%, p=0.014). No significant differences in distant failure-free survival (DFFS), disease-free survival (DFS), and overall survival were observed between groups. In subgroup analysis, the NCT arm showed superior DFFS and DFS in stage IV patients younger than 60 years. No significant difference in compliance and toxicity was observed between groups, except the radiation therapy duration was slightly shorter in the CRT arm (50.0 days vs. 53.9 days, p=0.018). Conclusion This study did not show the superiority of NCT followed by CCRT over CCRT alone. Because NCT could increase the risk of locoregional recurrences, it can only be considered in selected young patients with advanced stage IV disease. The role of NCT remains to be defined and should not be viewed as the standard of care.

Maximum Standardized Uptake Value of Pelvic Lymph Nodes in [18F]-Fluorodeoxyglucose Positron Emission Tomography Is a Prognostic Factor for Para-Aortic Lymph Node Recurrence in Pelvic Node-Positive Cervical Cancer Treated With Definitive Chemoradiotherapy.

Objectives This study aimed to identify prognostic factors for para-aortic lymph node (PALN) recurrence and their effect on survival outcomes in patients with pelvic node–positive squamous cell carcinoma (SCC) of the cervix treated with definitive concurrent chemoradiotherapy (CCRT). Materials and Methods Of the 116 patients with biopsy-proven SCC of the uterine cervix who underwent primary CCRT from 2007 to 2012, 48 patients with pelvic LN metastasis detected by [18F]-fluorodeoxyglucose positron emission tomography (FDG PET) were retrospectively analyzed. Patients with evidence of para-aortic lymphadenopathy were excluded. The whole pelvis was the standard irradiation field for all patients. The associations of age, stage, serum SCC antigen (SCC-Ag) level, maximum standardized uptake value (SUVmax), hemoglobin level, overall treatment time, adjuvant chemotherapy, and pelvic LN status with PALN recurrence and survival outcomes were evaluated. Results At a median follow-up of 34.0 months (range, 8–73 months), 10 (20.8%) patients had developed PALN recurrences. The relationship between pelvic LN FDG uptake and PALN recurrence was evaluated by the cutoff value (SUVmax = 3.85) determined by receiver operating characteristic curve analysis. The independent risk factors for PALN recurrence were FDG-avid pelvic LN (SUVPLN) greater than 3.85 (hazard ratio, 13.12; P = 0.025) and posttreatment SCC-Ag level greater than 2.0 (ng/mL) (hazard ratio, 20.69; P = 0.019). Patients with an SUVPLN greater than 3.85 were found to have significantly worse 5-year distant metastasis-free (51.0% vs 79.0%, P = 0.016) and progression-free survival (38.7% vs 67.3%, P = 0.011) than those with an SUVPLN less than or equal to 3.85. Conclusions SUVPLN is a statistically significant prognostic factor of PALN recurrence and survival after definitive CCRT for pelvic node–positive SCC of the uterine cervix.

The role of surgical clips in the evaluation of interfractional uncertainty for treatment of hepatobiliary and pancreatic cancer with postoperative radiotherapy

Purpose To evaluate the utility of implanted surgical clips for detecting interfractional errors in the treatment of hepatobiliary and pancreatic cancer with postoperative radiotherapy (PORT). Methods and Materials Twenty patients had been treated with PORT for locally advanced hepatobiliary or pancreatic cancer, from November 2014 to April 2016. Patients underwent computed tomography simulation and were treated in expiratory breathing phase. During treatment, orthogonal kilovoltage (kV) imaging was taken twice a week, and isocenter shifts were made to match bony anatomy. The difference in position of clips between kV images and digitally reconstructed radiographs was determined. Clips were consist of 3 proximal clips (clip_p, ≤2 cm) and 3 distal clips (clip_d, >2 cm), which were classified according to distance from treatment center. The interfractional displacements of clips were measured in the superior-inferior (SI), anterior-posterior (AP), and right-left (RL) directions. Results The translocation of clip was well correlated with diaphragm movement in 90.4% (190/210) of all images. The clip position errors greater than 5 mm were observed in 26.0% in SI, 1.8% in AP, and 5.4% in RL directions, respectively. Moreover, the clip position errors greater than 10 mm were observed in 1.9% in SI, 0.2% in AP, and 0.2% in RL directions, despite respiratory control. Conclusion Quantitative analysis of surgical clip displacement reflect respiratory motion, setup errors and postoperative change of intraabdominal organ position. Furthermore, position of clips is distinguished easily in verification images. The identification of the surgical clip position may lead to a significant improvement in the accuracy of upper abdominal radiation therapy.

Patterns of care for patients with nasopharyngeal carcinoma (KROG 11-06) in South Korea

Purpose To investigate the patterns of care for patients with nasopharyngeal carcinoma (NPC) in South Korea. Materials and Methods A multi-institutional retrospective study was performed (Korean Radiation Oncology Group [KROG] 11-06) on a total of 1,445 patients from 15 institutions. Results Of the 1,445 patients, more than half were stages III (39.9%) and IV (35.8%). In addition to patterns of care, we also investigated trends over time with the periods 1988-1993, 1994-2002, and 2003-2011. The frequencies of magnetic resonance imaging and positron emission tomography-computed tomography were markedly increased in the third period compared to previous 2 periods. Concurrent chemoradiation (CCRT) was performed on 894 patients (61.9%), neoadjuvant chemotherapy on 468 patients (32.4%), and adjuvant chemotherapy on 366 patients (25.3%). Of stage II-IV patients, CCRT performed on 78.8% in 2003-2011 compared to 15.0% in 1988-1993. For patients treated with CCRT, cisplatin was the most commonly used agent in 81.3% of patients. Over the periods of time, commonly used radiotherapy (RT) techniques were changed from 2-dimensional RT (1988-1993, 92.5%) to 3-dimensional RT (2003-2011, 35.5%) or intensity-modulated RT (IMRT; 2003-2011, 56.5%). Median RT doses given to primary tumors, high-risk lymphatics, and low-risk lymphatics were 70.0 Gy, 58.1 Gy, and 48.0 Gy, respectively. Adoption of IMRT increased the dose per fraction and escalated total radiation dose. Conclusion Assessment of the patterns of care for NPC patients in South Korea demonstrated that management for NPC including diagnostic imaging, treatment regimen, RT techniques and dose schedule, advanced in accordance with the international guidelines.

Neoadjuvant intra-arterial chemotherapy combined with radiotherapy and surgery in patients with advanced maxillary sinus cancer

Purpose The optimal treatment of advanced maxillary sinus cancer has been challenging for several decades. Intra-arterial chemotherapy (IAC) for head and neck cancer has been controversial. We have analyzed the long-term outcome of neoadjuvant IAC followed by radiation therapy (RT) and surgery. Materials and Methods Twenty-seven patients with advanced maxillary sinus cancer were treated between 1989 and 2002. Five-fluorouracil (5-FU, 500 mg/m2) was infused intra-arterially, and followed by RT (total 50.4 Gy/28 fractions). A planned surgery was performed 3 to 4 weeks after completion of IAC and RT. Results At a median follow-up of 77 months (range, 12 to 169 months), the 5-year rates of overall survival in all patients were 63%. The 5-year rates of overall survival of stage T3/T4 patients were 70.0% and 58.8%, respectively. Seven of fourteen patients with disease recurrence had a local recurrence alone. The 5-year actuarial local control rates in patients with stage T3/T4, and in all patients were 20.0%, 32.3%, and 27.4%, respectively. Overall response rate after the completion of IAC and RT was 70.3%. During the follow-up, seven patients (25.9%) showed mild to moderate late complications. The tumor extent (i.e., the involvement of either orbit and/or base of skull) appeared to be related with local recurrence. Conclusion Neoadjuvant IAC with 5-FU followed by RT and surgery may be effective to improve local tumor control in the patients with advanced maxillary sinus cancer. However, local failure was still the major cause of death. Further investigations are required to determine the optimal treatment schedule, radiotherapy techniques and chemotherapy regimens.