BACKGROUND. A number of conventional histopathologic features have been associated with recurrence of ductal carcinoma in situ (DCIS) after surgery alone and are included in the Van Nuys Pathologic Classification and Prognostic Index. To the authors' knowledge, very little is known regarding the prognostic significance of the many biologic markers that have been studied in DCIS in the past decade. METHODS. Clinical and pathologic data were analyzed from 151 patients who underwent wide local excision alone for DCIS that was diagnosed by mammography or as an incidental finding between 1982 and 2000. Using local disease recurrence as an endpoint, the authors sought to determine the prognostic significance of a large number of histopathologic parameters as well as biologic markers (estrogen receptor [ER], progesterone receptor [PR], p53, HER-2/neu, Ki-67, p21, and bcl-2), as determined by immunohistochemical staining of contemporary or archival tissue. RESULTS. With a median follow-up of 65 months, 42 recurrences were reported to occur between 11 months and 97 months after definitive surgery. In a univariate analysis, tumor size, Van Nuys pathologic classification, and degree of necrosis demonstrated significant correlations with the rate of recurrence. Tumor size, necrosis, nuclear grade, and comedonecrosis were found to be associated significantly with the time to disease recurrence. None of the biologic markers demonstrated a significant association with the rate of recurrence or the time to disease recurrence. In a multivariate analysis, only large tumor size (Van Nuys 2 or 3) and higher degrees of necrosis (Van Nuys 2 or 3) were found to be associated significantly with both the rate of recurrence and the time to recurrence. No biologic marker showed a significant correlation with recurrence. Using Classification and Regression-Tree Analysis and Tree-Structured Survival Analysis, PR Ͼ 3.5% and bcl-2 Ͻ 97.5% were associated with a higher recurrence rate in the subgroup of patients with small tumor size (Van Nuys size 1) and higher degrees of tumor necrosis (Van Nuys 2 or 3). CONCLUSIONS. The current results confirmed the value of conventional histopathologic parameters, as outlined in the Van Nuys classification system, in predicting local recurrence of DCIS. Using traditional logistic analyses, no significant correlation was found between a variety of biologic markers and disease recurrence.

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow-up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners. q 2007 Clinical Cytometry Society

Purpose: Increased incidence of ductal carcinoma in situ (DCIS) associated with mammographic screening for breast cancer has emphasized the challenges of managing this condition.The aim of this study was to identify informative clinical indicators of DCIS biology by molecular profiling. Experimental Design: Areas of in situ carcinoma, atypical ductal hyperplasia, and benign epithelium were microdissected from 46 invasive breast cancers. Oligonucleotide probes showing differential expression between DCIS associated with grade 1 and 3 invasive cancer were identified by microarray-based gene expression profiling. Expression at these probes was used to define a ''molecular grade'' subcategorization of all samples. The genomic basis of molecular grade was examined by array-based comparative genomic hybridization. Clinical course was examined in a cohort of 134 patients with DCIS treated by surgery alone. Results: DCIS samples were designated as low or high molecular grade based on expression at 173 probes. The low molecular grade subgroup included low (n = 10) and intermediate (n = 11) nuclear grade DCIS as well as all samples of atypical ductal hyperplasia (n = 4) and benign epithelium (n = 7). The high molecular grade subgroup included DCIS of intermediate (n = 7) and high (n = 19) nuclear grade. The character and degree of genomic aberration were distinct between molecular grade subgroups. A classification tree model including nuclear grade and Ki67 score accurately predicted molecular grade for 95.7% of samples. In an independent cohort, this showed a pattern of rapid disease recurrence for high molecular grade DCIS. Conclusions: Molecular profiling indicates a binary grading scheme for DCIS. This practical approach has potential to improve clinical evaluation of DCIS.