ABSTRACT
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.
ABSTRACT
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 [F]-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.
