The Presence of Extensive Retraction Clefts in Invasive Breast Carcinomas Correlates with Lymphatic Invasion and Nodal Metastasis and Predicts Poor Outcome – A Prospective Validation Study of 2702 Consecutive Cases
Geza Acs, Nazanin Khakpour, John Kiluk, M Catherine Lee, Christine Laronga. Moffitt Cancer Center, Tampa, FL; Women's Pathology Consultants, Ruffolo Hooper & Associates, Tampa, FL
Background: Retraction clefts (RC) around tumor cell nests are frequently seen in formalin-fixed paraffin embedded histologic material. We have previously reported that extensive RC in early stage breast cancers correlates with lymphatic vessel density and lymphatic tumor spread, and proposed that this feature may represent an early stage of lymphatic invasion (LVI). In the present study we have prospectively validated our prior results in a large independent series of breast cancers.
Design: We prospectively selected 2702 consecutive pT1-3 stage invasive breast carcinomas for the study. Cold ischemic time and duration of fixation was documented for all cases. All H&E stained slides were prospectively reviewed to determine tumor type and grade. The presence and extent of RC around tumor cell nests and the presence of LVI was also determined. LVI and micropapillary features in carcinomas were confirmed with immunohistochemical stains for podoplanin and epithelial membrane antigen, respectively. Micropapillary and mucinous carcinomas were excluded.
Results: Axillary lymph node assessment was performed in all cases. The median number of nodes removed was 3 (range 1-66). Nodal metastasis was present in 1069 cases; the median number of positive nodes was 2 (range 1-44). The correlation of the extent of RC with various clinicopathologic tumor features is summarized in the table. The presence of extensive RC was associated with LVI and nodal metastasis and predicted poor recurrence-free (p=0.0024) and overall (p=0.0075) survival.
|Histologic type||Ductal (NST)||2257||15||24.2±0.6||<0.0001|