Daniel Buitrago

A Panel of Four miRNAs Accurately Differentiates Malignant from Benign Indeterminate Thyroid Lesions on Fine Needle Aspiration

Purpose: Indeterminate thyroid lesions on fine needle aspiration (FNA) harbor malignancy in about 25% of cases. Hemi- or total thyroidectomy has, therefore, been routinely advocated for definitive diagnosis. In this study, we analyzed miRNA expression in indeterminate FNA samples and determined its prognostic effects on final pathologic diagnosis. Experimental Design: A predictive model was derived using 29 ex vivo indeterminate thyroid lesions on FNA to differentiate malignant from benign tumors at a tertiary referral center and validated on an independent set of 72 prospectively collected in vivo FNA samples. Expression levels of miR-222, miR-328, miR-197, miR-21, miR-181a, and miR-146b were determined using reverse transcriptase PCR. A statistical model was developed using the support vector machine (SVM) approach. Results: A SVM model with four miRNAs (miR-222, miR-328, miR-197, and miR-21) was initially estimated to have 86% predictive accuracy using cross-validation. When applied to the 72 independent in vivo validation samples, performance was actually better than predicted with a sensitivity of 100% and specificity of 86%, for a predictive accuracy of 90% in differentiating malignant from benign indeterminate lesions. When Hurthle cell lesions were excluded, overall accuracy improved to 97% with 100% sensitivity and 95% specificity. Conclusions: This study shows that that the expression of miR-222, miR-328, miR-197, and miR-21 combined in a predictive model is accurate at differentiating malignant from benign indeterminate thyroid lesions on FNA. These findings suggest that FNA miRNA analysis could be a useful adjunct in the management algorithm of patients with thyroid nodules. Clin Cancer Res; 18(7); 2032–8. ©2012 AACR.

Solid Predominant Histologic Subtype in Resected Stage I Lung Adenocarcinoma Is an Independent Predictor of Early, Extrathoracic, Multisite Recurrence and of Poor Postrecurrence Survival

PURPOSE To examine the significance of the proposed International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) histologic subtypes of lung adenocarcinoma for patterns of recurrence and, among patients who recur following resection of stage I lung adenocarcinoma, for postrecurrence survival (PRS). PATIENTS AND METHODS We reviewed patients with stage I lung adenocarcinoma who had undergone complete surgical resection from 1999 to 2009 (N = 1,120). Tumors were subtyped by using the IASLC/ATS/ERS classification. The effects of the dominant subtype on recurrence and, among patients who recurred, on PRS were investigated. RESULTS Of 1,120 patients identified, 188 had recurrent disease, 103 of whom died as a result of lung cancer. Among patients who recurred, 2-year PRS was 45%, and median PRS was 26.1 months. Compared with patients with nonsolid tumors, patients with solid predominant tumors had earlier (P = .007), more extrathoracic (P < .001), and more multisite (P = .011) recurrences. Multivariable analysis of primary tumor factors revealed that, among patients who recurred, solid predominant histologic pattern in the primary tumor (hazard ratio [HR], 1.76; P = .016), age older than 65 years (HR, 1.63; P = .01), and sublobar resection (HR, 1.6; P = .01) were significantly associated with worse PRS. Presence of extrathoracic metastasis (HR, 1.76; P = .013) and age older than 65 years at the time of recurrence (HR, 1.7; P = .014) were also significantly associated with worse PRS. CONCLUSION In patients with stage I primary lung adenocarcinoma, solid predominant subtype is an independent predictor of early recurrence and, among those patients who recur, of worse PRS. Our findings provide a rationale for investigating adjuvant therapy and identify novel therapeutic targets for patients with solid predominant lung adenocarcinoma.

Impact of Increasing Age on Cause-Specific Mortality and Morbidity in Patients With Stage I Non–Small-Cell Lung Cancer: A Competing Risks Analysis

Purpose To perform competing risks analysis and determine short- and long-term cancer- and noncancer-specific mortality and morbidity in patients who had undergone resection for stage I non-small-cell lung cancer (NSCLC). Patients and Methods Of 5,371 consecutive patients who had undergone curative-intent resection of primary lung cancer at our institution (2000 to 2011), 2,186 with pathologic stage I NSCLC were included in the analysis. All preoperative clinical variables known to affect outcomes were included in the analysis, specifically, Charlson comorbidity index, predicted postoperative (ppo) diffusing capacity of the lung for carbon monoxide, and ppo forced expiratory volume in 1 second. Cause-specific mortality analysis was performed with competing risks analysis. Results Of 2,186 patients, 1,532 (70.1%) were ≥ 65 years of age, including 638 (29.2%) ≥ 75 years of age. In patients < 65, 65 to 74, and ≥ 75 years of age, 5-year lung cancer-specific cumulative incidence of death (CID) was 7.5%, 10.7%, and 13.2%, respectively (overall, 10.4%); noncancer-specific CID was 1.8%, 4.9%, and 9.0%, respectively (overall, 5.3%). In patients ≥ 65 years of age, for up to 2.5 years after resection, noncancer-specific CID was higher than lung cancer-specific CID; the higher noncancer-specific, early-phase mortality was enhanced in patients ≥ 75 years of age than in those 65 to 74 years of age. Multivariable analysis showed that low ppo diffusing capacity of lung for carbon monoxide was an independent predictor of severe morbidity ( P < .001), 1-year mortality ( P < .001), and noncancer-specific mortality ( P < .001), whereas low ppo forced expiratory volume in 1 second was an independent predictor of lung cancer-specific mortality ( P = .002). Conclusion In patients who undergo curative-intent resection of stage I NSCLC, noncancer-specific mortality is a significant competing event, with an increasing impact as patient age increases.

Prognostic Impact of Immune Microenvironment in Lung Squamous Cell Carcinoma: Tumor-Infiltrating CD10+ Neutrophil/CD20+ Lymphocyte Ratio as an Independent Prognostic Factor

Introduction: We previously reported the prognostic significance of the lung adenocarcinoma immune microenvironment. In this study, we preformed comprehensive analysis of immune markers and their associations with prognosis in patients with lung squamous cell carcinoma. Methods: We reviewed surgically resected, solitary lung squamous cell carcinoma patients (n = 485; 1999–2009) who were randomly split into a training cohort (n = 331) and validation cohort (n = 154). We constructed tissue microarrays and performed immunostaining for CD3, CD45RO, CD8, CD4, FoxP3, CD20, CD68, CXCL12, CXCR4, CCR7, interleukin-7 receptor, and interleukin-12 receptor &bgr;2. Overall survival (OS) was analyzed using the log-rank test and the Cox proportional hazards model. Results: Analysis of single immune cell infiltration revealed that high tumor-infiltrating CD10+ neutrophils were associated with worse prognoses in the training cohort (p = 0.021). Analysis of biologically relevant immune cell combinations identified that patients with high CD10+ neutrophil and low CD20+ lymphocyte had a significantly worse OS (5-year OS, 42%) than those with other combinations of CD10 and CD20 (5-year OS, 62%; p < 0.001); this was confirmed in the validation cohort (p = 0.032). For the multivariate analysis, high CD10/low CD20 immune cell infiltration was an independent predictor of OS in both the training cohort (hazard ratio = 1.61, p = 0.006) and the validation cohort (hazard ratio = 1.75; p = 0.043). Conclusion: High CD10+/low CD20+ immune cell infiltration ratio is a significant prognostic factor of lung squamous cell carcinoma. Immunomodulatory therapy of tumor-specific neutrophil and B-lymphocyte responses may have applicability in the treatment of lung squamous cell carcinoma.

Calcimimetics versus parathyroidectomy for treatment of primary hyperparathyroidism: retrospective chart analysis of a prospective database.

Objective:This study aims to determine the efficacy of calcimimetics in improving bone mineral density (BMD) in patients with primary hyperparathyroidism (pHPT) and compare those results to patients undergoing parathyroidectomy. Background:Parathyroidectomy has been shown to improve BMD in pHPT, but calcimimetics have recently been advocated as a medical alternative to parathyroidectomy for pHPT. Materials and Methods:We identified 17 patients that were treated with calcimimetics for pHPT. Seventeen patients with pHPT who underwent parathyroidectomy served as surgical controls. Serum calcium level, parathyroid hormone (PTH) level, and femur and spine BMD T scores were compared before and 1 year after therapy. Results:Both groups were demographically matched. Calcium levels normalized in 70.6% of medically versus 100% of surgically treated patients (P = 0.026). PTH levels normalized in 35% of patients treated with calcimimetics versus 76% of surgical patients (P = 0.036). Femur BMD improved in 18.8% of medically treated patients versus 58.8% of surgical patients (P = 0.032). Spine BMD improved in 70.6% of medically treated patients versus 82.4% of surgical patients (P = 0.69). Further analysis demonstrated that regardless of treatment, normalization of PTH was associated with significant improvement in femur (P = 0.03) and spine BMD (P < 0.001). Normalization of calcium without normalization of PTH did not impact BMD. Conclusions:Parathyroidectomy results in greater normalization of serum calcium and PTH levels and significantly improves cortical BMD compared to calcimimetics. Regardless of treatment, normalization of PTH is associated with significant improvement in spine and femur BMD, suggesting that the superior effects of surgery may be mediated by better control of PTH.

Risk stratification of indeterminate thyroid fine-needle aspiration biopsy specimens based on mutation analysis

BACKGROUND Mutation analysis is potentially a powerful tool to enhance the diagnostic accuracy of thyroid fine-needle aspiration (FNA) biopsy specimens. However, some clinicians may rely on a negative mutation panel to exclude malignancy. We aimed to determine the malignancy rate in indeterminate lesions with negative mutation analysis. METHODS A literature review established a mutation analysis model using the prevalence of BRAF, RET, RAS, and PAX8/peroxisome proliferator-activated receptor-γ mutations in indeterminate lesions. This model was applied retrospectively to a study cohort of 466 consecutive indeterminate lesions that underwent hemi- or total thyroidectomy for definitive diagnosis, to evaluate its accuracy for identifying malignancy. RESULTS Of 466 indeterminate lesions in the study, 30% (139) were malignant. These included 66 cases of papillary thyroid cancer, 45 cases of follicular variant of papillary thyroid cancer, 18 cases of follicular thyroid cancer, and 10 others. The risk of malignancy was 42% when cytologic atypia was present vs 17% without. The mutation analysis model would correctly identify only 48 of 139 (34%) of malignant indeterminate lesions. Therefore, when mutation analysis is negative, the overall risk of malignancy would be 23%. When atypia is present, the risk of malignancy would be 31% vs 13% in lesions without. CONCLUSION Indeterminate lesions with a negative mutation analysis still carry a significant risk of malignancy, especially in the presence of atypia, requiring surgery for definitive diagnosis.

Small RNA Sequencing for Profiling MicroRNAs in Long-Term Preserved Formalin-Fixed and Paraffin-Embedded Non-Small Cell Lung Cancer Tumor Specimens

Background The preservation of microRNAs in formalin-fixed and paraffin-embedded (FFPE) tissue makes them particularly useful for biomarker studies. The utility of small RNA sequencing for microRNA expression profiling of FFPE samples has yet to be determined. Methods Total RNA was extracted from de-paraffinized and proteinase K-treated FFPE specimens (15–20 years old) of 8 human lung adenocarcinoma tumors by affinity chromatography on silica columns. MicroRNAs in the RNA preparations were quantified by the Illumina HiSeq 2000 sequencing platform with sequencing libraries prepared with the TruSeq Small RNA Sample Preparation Kit (version 2.0) to obtain unpaired reads of 50 b for small RNA fragments. MicroRNAs were also quantified using Agilent Human miRNA (release 16.0) microarrays that can detect 1,205 mature microRNAs and by quantitative reverse transcription (RT)-PCR assays. Results Between 9.1–16.9 million reads were obtained by small RNA sequencing of extracted RNA samples. Of these, only 0.6–2.3% (mean = 1.5%) represented microRNAs. The sequencing method detected 454–625 microRNAs/sample (mean = 550) compared with 200–349 (mean = 286) microRNAs detected by microarray. In Spearman correlation analyses, the average correlation coefficient for the 126 microRNAs detected in all samples by both methods was 0.37, and >0.5 for 63 microRNAs. In correlation analyses of the sequencing- and RT-PCR-based measurements, the coefficients were 0.19–0.95 (mean = 0.73) and >0.7, respectively, for 7 of 9 examined microRNAs. The average inter-replicate Spearman correlation coefficient for the sequencing method was 0.81. Conclusions Small RNA sequencing can be used to obtain microRNA profiles of FFPE tissue specimens with performance characteristics similar to those of microarrays, in spite of the fragmentation of ribosomal and messenger RNAs that reduces the methods informative capacity. The accuracy of the method can conceivably be improved by increasing sequencing depth and/or depleting FFPE tissue RNAs of ribosomal RNA fragments.

Current concepts in severe adult tracheobronchomalacia: evaluation and treatment

There is increasing recognition of tracheobronchomalacia (TBM) in patients with respiratory complaints, though its true incidence in the adult population remains unknown. Most of these patients have an acquired form of severe diffuse TBM of unclear etiology. The mainstays of diagnosis are dynamic (inspiratory and expiratory) airway computed tomography (CT) scan and dynamic flexible bronchoscopy with forced expiratory maneuvers. While the prevailing definition of TBM is 50% reduction in cross-sectional area, a high proportion of healthy volunteers meet this threshold, thus this threshold fails to identify patients that might benefit from intervention. Therefore, we consider complete or near-complete collapse (>90% reduction in cross-sectional area) of the airway to be severe enough to warrant potential intervention. Surgical central airway stabilization by posterior mesh splinting (tracheobronchoplasty) effectively corrects malacic airways and has been shown to lead to significant improvement in symptoms, health-related quality of life, as well as functional and exercise capacity in carefully selected adults with severe diffuse TBM. A short-term stent trial clarifies a patients candidacy for surgical intervention. Coordination of care between experienced interventional pulmonologists, radiologists, and thoracic surgeons is essential for optimal outcomes.

The Impact of Incidental Identification on the Stage at Presentation of Lower Gastrointestinal Carcinoids

BACKGROUND Over the past 3 decades, there has been a significant increase in the incidence of gastrointestinal carcinoid tumors in the United States. Incidentally discovered carcinoids in the lower gastrointestinal tract have probably contributed to this increase. In this study we aimed to compare the clinicopathologic characteristics of incidentally discovered carcinoids of the small and large bowel with those identified as a result of symptoms. STUDY DESIGN We performed a retrospective review of 58 consecutive patients with nonappendiceal gastrointestinal carcinoids: 30 small bowel and 28 large bowel. We compared asymptomatic patients with lower gastrointestinal tract carcinoids identified by routine colonoscopy with those identified as a result of symptoms. RESULTS Twenty-eight (48.3%) incidentally identified carcinoids (15 small bowel and 13 large bowel) were compared with 30 (51.7%) symptomatic carcinoids. Incidental ileal carcinoids were similar in size (mean ± SD, 1.3 ± 0.61 vs 1.7 ± 1.13, p = 0.45) and incidence of lymph node metastases (12 in 15 vs 9 in 15, p = 0.43) to symptomatic ileal carcinoids. However, incidental ileal carcinoids had a lower incidence of distant metastases (1 in 15 vs 7 in 15, p = 0.035) compared with symptomatic ileal carcinoids. There was no difference in tumor size, extent of lymph node metastases, or distant metastases between incidental and symptomatic large bowel carcinoids. CONCLUSIONS Ileal carcinoids identified at screening colonoscopy are associated with a significantly decreased incidence of distant metastases compared with those identified after development of symptoms, despite similar size and extent of lymph node metastases. However, incidental large bowel carcinoids appear to have similar staging to those identified as a result of symptoms.

Resection of Primary and Secondary Tumors of the Sternum: An Analysis of Prognostic Variables

BACKGROUND We sought to determine the prognostic variables associated with overall survival (OS) and recurrence-free probability (RFP) in patients with primary and secondary sternal tumors treated with surgical resection. METHODS A retrospective analysis of patients who underwent resection of primary or secondary sternal tumors at 2 cancer institutes between 1995 and 2013 was performed. OS and RFP were estimated using the Kaplan-Meier method, and predictors of OS and RFP were analyzed using the Cox proportional hazards model. RESULTS Sternal resection was performed in 78 patients with curative (67 [86%]) or palliative (6 [8%]) intent. Seventy-three patients (94%) had malignant tumors, of which 28 (36%) were primary and 45 (57%) were secondary malignancies. Sternal resections were complete in 13 patients (17%) and partial in 65 (83%). There were no perioperative deaths, and grade III/IV complications were noted in 17 patients (22%). The 5-year OS was 80% for patients with primary malignant tumors, 73% for patients with nonbreast secondary malignant tumors, and 58% for patients with breast tumors (p = 0.85). In the overall cohort, R0 resection was associated with prolonged 5-year OS (84% vs 20%) on univariate (p = 0.004) and multivariate (adjusted hazard ratio, 3.37; p = 0.029) analysis. On subgroup analysis, R0 resection was associated with improved OS and RFP only for patients with primary malignant tumors. CONCLUSIONS Sternal resection can achieve favorable OS for patients with primary and secondary sternal tumors. R0 resection is associated with improved 5-year OS and RFP in patients with primary malignant tumors. We did not detect a similar effect in patients with breast or nonbreast secondary tumors.