Citations

Treatment with abiraterone acetate and prednisone (AA/P) prolongs survival in metastatic castration-resistant prostate cancer (mCRPC) patients. We evaluated the genetic variation in CYP17A1 as predictive of response to AA/P. A prospective collection of germline DNA prior to AA/P initiation and follow-up of a mCRPC cohort was performed. Five common single-nucleotide polymorphisms (SNPs) in CYP17A1 identified using a haplotype-based tagging algorithm were genotyped. Clinical outcomes included biochemical response and time to biochemical progression on AA/P. Logistic regression was used to assess the association between tag SNPs and biochemical response. Proportional hazards regression was used to assess the association between tag SNPs and time to biochemical progression. Odds or hazard ratio per minor allele were estimated and p-values below 0.05 were considered statistically significant. Germline DNA was successfully genotyped for four tag SNPs in 87 patients. The median age was 73 years (54–90); the median prostate-specific antigen was 66 ng/dL (0.1–99.9). A single SNP, rs2486758, was associated with lower odds of experiencing a biochemical response (Odds ratio 0.22, 95% confidence interval 0.07–0.63, p = 0.005) and a shorter time to biochemical progression (Hazard ratio 2.23, 95% confidence interval 1.39–3.56, p < 0.001). This tag SNP located in the promoter region of CYP17A1 will need further validation as a predictive biomarker for AA/P therapy.

Goals: Our aim was to develop a scoring system to predict risk of microscopic colitis (MC), to identify patients at low risk, potentially avoiding unnecessary biopsies. Background: Patients with chronic diarrhea often undergo colonoscopy with biopsy, but few have histologic abnormalities. Study: We conducted a retrospective study of patients with chronic diarrhea and a macroscopically normal colonoscopy at our institution over a 9-month period. Multivariable logistic regression assessed the association between predictors and the presence of biopsy-proven MC. Results: The derivation cohort included 617 patients. Median age was 55.1 (39.6 to 68.1) years; 397 (64.3%) were female and 81 (13.1%) had MC. Age ≥55 years, duration of diarrhea ≤6 months, ≥5 bowel movements per day, body mass index <30 kg/m2, current smoking, and current use of selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitorss and non-steroidal anti-inflammatory drugs were independently associated with MC. A score of ≥10 points in our scoring system, yielded an area under the ROC curve (AUC) of 0.83 with a sensitivity of 93% and specificity of 49% in predicting which patients have MC. The negative predictive value (NPV) was 97.8% (95.0% to 99.1%). In the validation cohort, the scoring system performed similarly (AUC 0.79, sensitivity 91%, specificity 49%, NPV 97%). By avoiding biopsies in patients at low risk of having MC, costs associated with colon biopsies could be reduced by almost 43%. Conclusion: This scoring system including 7 clinical variables was able to identify patients unlikely to have MC, with excellent sensitivity, reasonable specificity, and a high NPV, translating into important potential cost savings.

Response to therapy in newly diagnosed symptomatic multiple myeloma (NDMM) can impact long‐term outcomes. It is not clear if baseline laboratory parameters can predict an early, deep response. Totally 1,304 patients with NDMM seen between 2001 and 2013 at Mayo Clinic Rochester were studied. The association between baseline laboratory parameters and early, deep response defined as a very good partial response or better (VGPR+) within four cycles of treatment was investigated. Multivariable logistic regression was used to assess the associations between the parameters of interest and response. Multivariable proportional hazards regression was used to assess the association between response and overall survival. In the entire cohort, greater absolute free light chain (FLC) differences (OR 2.38, 95% CI 1.48–3.82), younger age (OR 2.18, 95% CI 1.28–3.71), lower hemoglobin (OR 1.68, 95% CI 1.12–2.54), and IgA myeloma (OR 1.66, 95% CI 1.10–2.51) were associated with increased odds of achieving VGPR+ after four cycles. Among patients receiving novel agents in general and immunomodulators in particular, these effects were more pronounced. In patients receiving proteasome‐inhibitors, higher creatinine (OR 3.83, 95% CI 1.37–10.1), lower calcium (OR 3.37, 95% CI 1.36–8.35), and greater absolute FLC differences (OR 2.50, 95% CI 1.10–5.71) were associated with better response. In a landmark analysis at 4 months from diagnosis, achieving VGPR+ was associated with decreased risk of subsequent mortality (HR 0.69, 95% CI 0.53–0.86). In summary, several parameters were associated with an early, deep response to treatment, revealing distinct sets of predictors for immunomodulator‐ and proteasome‐inhibitor‐containing regimens. Achieving VGPR+ after four cycles translated into increased overall survival. Am. J. Hematol. 90:888–891, 2015. © 2015 Wiley Periodicals, Inc.