Abstract Background: Prior research on the associations of p16, COX-2, and Ki67 immunopositivity in ductal carcinoma in situ (DCIS) tissue with the risk of subsequent ipsilateral invasive breast cancer (IBC) is limited. Methods: In a case–control study nested in a cohort of women diagnosed with DCIS, immunostaining for p16, COX-2, and Ki67 was performed on DCIS tissue from those who developed subsequent ipsilateral IBC (cases; n = 146) and on matched subjects who did not develop IBC (controls; n = 273). Conditional logistic regression was used to estimate ORs and 95% confidence intervals for the associations between immunopositivity for p16, COX-2, and Ki67 and the risk of subsequent ipsilateral IBC. Results: There was no association between p16, COX-2, and Ki67 immunopositivity, examined either individually or in combination, and a risk of ipsilateral IBC. Compared with all other groups, the multivariable OR (95% confidence interval) for women who were triple positive for the three markers was 1.16 (0.38–3.54). Conclusions: p16, COX-2, and Ki67 immunopositivity was not associated with altered risk of ipsilateral IBC in women with DCIS. Impact: p16, COX-2, and Ki67 may not be prognostic for ipsilateral IBC in women with DCIS.
Molecular markers of risk of subsequent invasive breast cancer in women with ductal carcinoma in situ: protocol for a population-based cohort study
Introduction Ductal carcinoma in situ (DCIS) of the breast is a non-obligate precursor of invasive breast cancer (IBC). Many DCIS patients are either undertreated or overtreated. The overarching goal of the study described here is to facilitate detection of patients with DCIS at risk of IBC development. Here, we propose to use risk factor data and formalin-fixed paraffin-embedded (FFPE) DCIS tissue from a large, ethnically diverse, population-based cohort of 8175 women with a first diagnosis of DCIS and followed for subsequent IBC to: identify/validate miRNA expression changes in DCIS tissue associated with risk of subsequent IBC; evaluate ipsilateral IBC risk in association with two previously identified marker sets (triple immunopositivity for p16, COX-2, Ki67; Oncotype DX Breast DCIS score); examine the association of risk factor data with IBC risk. Methods and analysis We are conducting a series of case–control studies nested within the cohort. Cases are women with DCIS who developed subsequent IBC; controls (2/case) are matched to cases on calendar year of and age at DCIS diagnosis. We project 485 cases/970 controls in the aim focused on risk factors. We estimate obtaining FFPE tissue for 320 cases/640 controls for the aim focused on miRNAs; of these, 173 cases/346 controls will be included in the aim focused on p16, COX-2 and Ki67 immunopositivity, and of the latter, 156 case–control pairs will be included in the aim focused on the Oncotype DX Breast DCIS score®. Multivariate conditional logistic regression will be used for statistical analyses. Ethics and dissemination Ethics approval was obtained from the Institutional Review Boards of Albert Einstein College of Medicine (IRB 2014-3611), Kaiser Permanente Colorado, Kaiser Permanente Hawaii, Henry Ford Health System, Mayo Clinic, Marshfield Clinic Research Institute and Hackensack Meridian Health, and from Lifespan Research Protection Office. The study results will be presented at meetings and published in peer-reviewed journals.
The CAP-IASLC-AMP molecular testing guideline for the selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors.
11085 Background: The College of American Pathologists (CAP), the International Association for the Study of Lung Cancer (IASLC), and the Association for Molecular Pathology (AMP) jointly initiated an effort to establish evidence-based recommendations for the molecular analysis of lung cancers required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed. Methods: Three co-chairs without relevant conflicts of interest were selected, one from each of the sponsoring societies: CAP (P.T.C.), IASLC (M.L.), and AMP (N.I.L.). Writing and advisory panels were formed from additional experts from these societies. Unbiased literature searches were performed to capture articles up to February 2012, yielding 1,533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for relevance. Evidence was formally graded for each of the recommendations first formulated by the co-chairs and panel members at a public meeting. Each guideline section was assigned to at least two panelists. Successive drafts were circulated for comments to the writing panel, the advisory panel, the public (online posting), and the three professional societies. Results: We generated 37 guideline items addressing 14 areas of EGFR and ALK testing. The major, evidence-based recommendations are to test for EGFR mutations and ALK fusions in all patients with advanced stage adenocarcinoma, regardless of sex, race, or smoking history, and to prioritize EGFR and ALK testing over other molecular predictive tests. Recommendations and expert consensus opinions were generated for all other key aspects of EGFR and ALK testing in lung cancer related to oncology and pathology practice and technical issues in molecular testing. Conclusions: As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards and thereby improving patient outcomes.
Atypical Lipomatous Tumor/Well-Differentiated Liposarcoma With Features Mimicking Spindle Cell Lipoma
Atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) and spindle cell lipoma are lipomatous tumors with distinct clinical, molecular, and prognostic features. Although histological and immunophenotypic features can overlap between ALT/WDL and spindle cell lipoma, the oncogenesis and clinical behavior are markedly different. In borderline cases, molecular analysis for MDM2 or CDK4 amplification can aid in distinguishing ALT/WDL from spindle cell lipoma. Although dedifferentiated liposarcoma has been reported to harbor both MDM2 amplification and loss of the RB1 region, we are not aware of a reported RB1 loss in well-differentiated ALT/WDL. In this article, we present a 69-year-old woman with a lipomatous tumor in the gluteal region that histologically, immunohistochemically, and molecularly mimicked spindle cell lipoma (with positive immunohistochemical staining for CD34 and loss of the RB1 gene region), yet harbored amplification of MDM2 and CDK4 confirmed by fluorescence in situ hybridization, supporting classification as ALT/WDL. This case strengthens the argument that in atypical clinical contexts, molecular studies for MDM2/CDK4 should be considered in tumors resembling spindle cell lipoma.
Evaluation and Adaptation of a Laboratory-Based cDNA Library Preparation Protocol for Retrospective Sequencing of Archived MicroRNAs from up to 35-Year-Old Clinical FFPE Specimens
Formalin-fixed paraffin-embedded (FFPE) specimens, when used in conjunction with patient clinical data history, represent an invaluable resource for molecular studies of cancer. Even though nucleic acids extracted from archived FFPE tissues are degraded, their molecular analysis has become possible. In this study, we optimized a laboratory-based next-generation sequencing barcoded cDNA library preparation protocol for analysis of small RNAs recovered from archived FFPE tissues. Using matched fresh and FFPE specimens, we evaluated the robustness and reproducibility of our optimized approach, as well as its applicability to archived clinical specimens stored for up to 35 years. We then evaluated this cDNA library preparation protocol by performing a miRNA expression analysis of archived breast ductal carcinoma in situ (DCIS) specimens, selected for their relation to the risk of subsequent breast cancer development and obtained from six different institutions. Our analyses identified six miRNAs (miR-29a, miR-221, miR-375, miR-184, miR-363, miR-455-5p) differentially expressed between DCIS lesions from women who subsequently developed an invasive breast cancer (cases) and women who did not develop invasive breast cancer within the same time interval (control). Our thorough evaluation and application of this laboratory-based miRNA sequencing analysis indicates that the preparation of small RNA cDNA libraries can reliably be performed on older, archived, clinically-classified specimens.