BACKGROUND. Tumor content in circulating cell-free DNA (cfDNA) is a promising biomarker, but longitudinal dynamics of tumor-derived and non–tumor-derived cfDNA through multiple courses of therapy have not been well described. METHODS. CfDNA from 663 plasma samples from 140 patients with castration-resistant prostate cancer (CRPC) was subject to sparse whole genome sequencing. Tumor fraction (TFx) estimated using the computational tool ichorCNA was correlated with clinical features and responses to therapy. RESULTS. TFx associated with the number of bone metastases (median TFx = 0.014 with no bone metastases, 0.047 with 1–3 bone metastases, 0.190 for 4+ bone metastases; P < 0.0001) and with visceral metastases ( P < 0.0001). In multivariable analysis, TFx remained associated with metastasis location ( P = 0.042); TFx was positively correlated with alkaline phosphatase ( P = 0.0227) and negatively correlated with hemoglobin (Hgb) ( P < 0.001), but it was not correlated with prostate specific antigen (PSA) ( P = 0.75). Tumor-derived and non–tumor-derived cfDNA track together and do not increase with generalized tissue damage from chemotherapy or radiation at the time scales examined. All new treatments that led to ≥30% PSA decline at 6 weeks were associated with TFx decline when baseline TFx was >7%; however, TFx in patients being subsequently maintained on secondary hormonal therapy was quite dynamic. CONCLUSION. TFx correlates with clinical features associated with overall survival in CRPC, and TFx decline is a promising biomarker for initial therapeutic response. TRIAL REGISTRATION. Dana-Farber/Harvard Cancer Center (DF/HCC) protocol no. 18-135. FUNDING. Wong Family Award in Translational Oncology, Dana Farber Cancer Institute Medical Oncology grant, Gerstner Family Foundation, Janssen Pharmaceuticals Inc., and Koch Institute Support (core) grant P30-CA14051 from the National Cancer Institute (NCI).

Recent studies have shown that administering the aromatase inhibitor exemestane after 2–3 years of tamoxifen therapy significantly improves disease-free survival in postmenopausal women with primary breast cancer in comparison with standard 5-year tamoxifen treatment. Although many of the adverse effects associated with exemestane and tamoxifen have been analysed, there are no comparative data concerning body weight and body composition. The aim of this randomised study was to evaluate the longitudinal changes in body composition and lipid profiles in postmenopausal women switched from tamoxifen to exemestane. In total, 60 overweight or obese postmenopausal patients were enrolled. Their anthropometric data, body composition, including fat mass (FM) and fat-free mass (FFM), and lipid profiles, caloric intake and physical activity were assessed 1 week before randomisation, and 6 and 12 months later. In all, 55 patients (27 on tamoxifen and 28 on exemestane) completed the 1-year study period. Fat mass had significantly decreased by month 12 in the exemestane, but not in the tamoxifen group; the between-group difference was statistically significant (P<0.01). The FFM/FM ratio had significantly increased in the exemestane group, but not the tamoxifen group; the between-group difference was statistically significant (P<0.05). Triglycerides and high-density lipoprotein cholesterol significantly decreased (P<0.01; P<0.05), and low-density lipoprotein cholesterol significantly increased (P<0.01) in the exemestane group at the end of the 1-year study period. Our findings suggest that switching patients to adjuvant exemestane treatment after at least 2 years of tamoxifen therapy may be associated with an advantage over continuing adjuvant tamoxifen treatment in terms of body composition.

Purpose: GOLFIG chemoimmunotherapy regimen proved to be a safe and very active chemoimmunotherapy regimen in advanced colon cancer patients. We have thus investigated the immunobiological feedback to the treatment and its possible correlation with the clinical outcome of these patients. Experimental Design: This clinical and immunologic study involved 46 patients, 27 males and 19 females, enrolled in the GOLFIG-1 phase II trial who received gemcitabine (1,000 mg/m² on days 1 and 15), oxaliplatin (85 mg/m² on days 2 and 16), levofolinic acid (100 mg/m² on days 1, 2, 15, and 16), and 5-fluorouracil (400 mg/m² as a bolus, and 800 mg/m² as a 24-hour infusion on days 1, 2, 15, and 16) followed by s.c. granulocyte macrophage colony-stimulating factor (100 μg, on days 3-7) and interleukin 2 (0.5 × 10⁶ IU twice a day on days 8-14 and 17-29). Results: The regimen was confirmed to be safe and very active in pretreated patients with metastatic colorectal cancer. A subgroup analysis of these patients revealed a prolonged time to progression and survival in six patients who developed late signs of autoimmunity. A multivariate analysis validated the occurrence of autoimmunity signs as an independent predictor of favorable outcome. A parallel immunologic study detected in the peripheral blood mononuclear cells of these patients a progressive increase in lymphocyte and eosinophil counts, amplification in central memory, a marked depletion of immunosuppressive regulatory T cells, and activation of colon cancer–specific cytotoxic T cells. Conclusions: Our results suggest that immunity feedback to GOLFIG regimen and its antitumor activity are tightly correlated.