Jihoon Lim

Alcohol Abuse Decreases Pelvic Control and Survival in Cervical Cancer: An Opportunity of Lifestyle Intervention for Outcome Improvement

Purpose: We examined the incidence and the effect of alcohol abuse on pelvic control (PC), disease-free survival (DFS), and overall survival (OS) in locally advanced cervical cancer patients undergoing definitive radiation therapy (RT). Methods: Between 2007 and 2013, 95 patients treated with RT were reviewed, and the tumor characteristics, the RT dose, the treatment time, chemotherapy, and the number of cycles were recorded. The association between alcohol abuse and DFS, OS, and the duration of PC was analyzed using multivariable Cox proportional hazards models. Results: Of the 95 patients with an average age of 54.8 years (range, 27 to 91 y), 30% were FIGO stage 1B1, 1B2, 2A, 52% stage 2B, 3A; and 18% stage 3B; 86% of the patients were treated with weekly cisplatin chemotherapy. Alcohol history showed that 10 (10.5%) patients met the CDC criteria for heavy alcohol use. With a mean follow-up time of 2 years, 85 patients (88.5%) achieved PC and 86 patients (90.5%) were free of distant metastasis. A total of 82 patients (86.3%) were alive at the last follow-up. When controlling for the total treatment time, excessive alcohol abuse was significantly associated with a decrease in DFS (P=0.005; hazard ratio [HR], 6.19; 95% confidence interval [CI]: 1.73, 22.18), OS (P=0.001; HR, 6.68; 95% CI: 2.10, 21.26), and PC (P=0.029; HR, 3.10; 95% CI: 1.13, 8.56) on univariable analysis. On multivariable analysis, excessive alcohol abuse was significantly associated with a decrease in DFS (P=0.005; HR, 10.57; 95% CI: 2.07, 53.93) and OS (P=0.001; HR, 10.80; 95% CI: 2.57, 45.40). Conclusions: In this small hypothesis-generating series of patients with heavy alcohol use, the data support the association that heavy alcohol use increases the risk of cancer recurrence and mortality. Additional research is required to better define the patient- and treatment-related factors that may be targeted for intervention.

The impact of maximum rectal distention and tandem angle on rectal dose delivered in 3D planned gynecologic high dose-rate brachytherapy.

Objective Computed tomography–based treatment planning for cervical cancer has allowed investigation into the volumetric radiation dose delivered to the rectum. The goal of intracavitary brachytherapy is to maximize the tumor dose while decreasing the dose to normal tissue like the rectum. We investigated the effects of tandem angle and maximum rectal distention on rectal dose delivered in HDR brachytherapy for locally advanced cervical cancer. Materials and Methods Between July 2007 and January 2010, 97 brachytherapy treatment planning computed tomographic scans from the first and last implant of 51 patients with locally advanced cervical cancer were reviewed. The rectum was manually contoured from the ischial tuberosity to the bottom of the sacroiliac joint. The maximum rectal distention was determined by measuring the largest anterior-posterior diameter of the rectum superior to the tandem ring and inferior to the end of the applicator. A volumetric measurement of the maximum and mean rectal dose, dose to 2 cc (D2cc), dose to 1cc (D1cc) of the rectum was calculated. The tandem angle and the Internal Commission on Radiation Units and Measurement rectal point were recorded, and a dose volume histogram was referenced. Results The mean maximum rectal distention was 3.01 cm. The mean D1cc, D2cc, mean rectal dose, maximum rectal dose, and Internal Commission on Radiation Units and Measurement rectal dose were 3.03 Gy, 2.78 Gy, 4.19 cGy, 1.40 cGy, and 2.99 Gy per treatment, respectively. In a multivariate analysis controlling for surface area, tandem angle, and body mass index, there was a significant increase in D2cc with increasing rectal distention (P = 0.016). There were no significant findings when observing the effects of tandem angle on D2cc. Conclusion Rectal distention significantly affects D2cc delivered in HDR brachytherapy. In contrast, tandem angle does not. Concerted efforts to decrease rectal distention should be considered during treatment planning and delivery.

Smoking Decreases Survival in Locally Advanced Cervical Cancer Treated With Radiation.

Purpose: To study the prevalence and effect of smoking on cervical cancer recurrence and mortality in patients undergoing definitive treatment with radiation. Materials and Methods: Between July 2007 and September 2013, 96 locally advanced cervical cancer patients received definitive radiation or chemoradiation followed by brachytherapy. Smoking status was obtained from prospective intake questionnaires and quantified by pack-years. Pelvic control (PC), disease-free survival (DFS), and overall survival (OS) were analyzed by multivariable Cox proportional hazards models. Results: Smoking history included 51 (53.1%) nonsmokers, 45 active smokers, and former smokers: 20 (20.8%) with 1 to 20 pack-years and 25 (26%) with 21+ pack-years. With a median follow-up of 2 years on univariate analysis, the impact of 1 to 20 pack-years on PC, DFS, and OS relative to nonsmokers was hazard ratio (HR) 4.29 (95% confidence interval [CI], 1.36-14.1; P=0.014), 4.99 (95% CI, 1.21-22.4; P=0.027), and 4.77 (95% CI, 1.34-17.8; P=0.017), respectively. For patients with 21+ pack-years, the impact on PC, DFS, and OS was HR=6.13 (95% CI, 2.29-18.6; P<0.001), 7.24 (95% CI, 2.28-29.1; P=0.001), and 4.21 (95% CI, 1.26-15.4; P=0.02). On multivariate analysis, there remained a significant difference of 1 to 20 pack-years smoking history on OS relative to nonsmokers, HR=4.68 (95% CI, 1.02-29; P=0.047). For patients with 21+ pack-years smoking history, there continued to be a negative impact on PC and DFS, HR=5.66 (95% CI, 1.7-22.18; P=0.004) and HR=6.89 (95% CI, 1.54-42; P=0.011), respectively. Conclusions: Former and active tobacco smoking during radiation therapy for cervical cancer is associated with unfavorable PC, DFS, and OS outcomes. The increased number of smoking pack-years conferred a worse outcome effect in those treated with radiation.

Dose delivered to the lumbosacral plexus from high-dose-rate brachytherapy for cervical cancer

Objective To calculate dose delivered to the lumbosacral plexus (LSP) with cervical brachytherapy using 3-dimensional imaging, and to compare this with the position of the tandem in the pelvis using bony landmarks. We also report long-term LSP toxicity outcomes. Methods and Materials Treatment planning images from 55 patients treated with tandem and ring brachytherapy from October 2009 through November 2012 were reviewed. The LSP was contoured on planning computed tomographic scans to calculate dose received. Lumbosacral plexus dose was studied as a function of tandem distance from the sacrum and pubic symphysis (STratio) measured on digitally reconstructed radiographs. Patient and implant characteristics were included as covariates on LSP dose. Clinical follow up on LSP toxicity was recorded. Results Patients were prescribed 550 to 700 cGy using computed tomography–based imaged-guided brachytherapy for 4 to 5 fractions. The maximum dose to 2 cc (D2cc) of LSP ranged from 44 to 287 cGy per implant. The median D2cc was 118 cGy, corresponding to 18% of prescription dose. Patients with an STratio less than 0.33 (closer to the sacrum) and at least 0.33 had median LSP doses of 138 and 98 cGy, respectively. Lumbosacral plexus dose did not change significantly with body mass index, uterus position, or tumor stage. Two patients reported symptoms of peripheral neuropathy, with a median follow-up of 14.7 months. Conclusions The mean D2cc per fraction to the LSP is roughly 20% of the prescribed high dose-rate and varies with the position of the tandem from the sacrum. The dose threshold for radiation-induced neuropathy of the LSP remains undefined.