Effect of Formalin Fixation on Surgical Margins in Breast Cancer Surgical Specimen

Abstract

Margin analysis in breast surgery is an important predictor of local recurrence and can have vital impact on the postoperative treatment planning. Objective. The aim was to assess the mean reduction in the closest tumor-free surgical margin in millimeters of breast cancer specimens following formalin fixation. Materials and Methods. We conducted a cross-sectional study at the Aga Khan University Hospital from March 30, 2010 to January 20, 2011. One hundred consecutive breast tumour surgical specimens which had macroscopically visible tumour were included. The cancer type included both in situ and invasive cancers. Excluded were the patients who had previous surgery or systemic/radiation therapy. The closest tumor-free margin was recorded and compared with the margin after formalin fixation. P value of <0.05 was considered significant. Results. The mean age of our 100 patients was 53 years with the majority of the patients having undergone mastectomy for predominantly invasive ductal carcinoma. Following formalin fixation, the mean reduction of the closest tumor-free margin was noted as 2.14 mm which was found statistically significant. Conclusion. Considerable shrinkage of tumor-free surgical margins of breast cancer specimen was noted after formalin fixation. This inference can have implications on the postoperative management plan.

Which factors influence MRI-pathology concordance of tumour size measurements in breast cancer?

“…Krekel et al found no change of tumourfree margins or tumour shrinkage of breast cancer specimen following formalin fixation [31]. However, authors have shown that shrinkage affects surrounding tissue and influences tumour margins, rather than tumour size itself [32,33]. Therefore, underestimation of real tumour size by histopathology due to formalin fixation may be discussed in case the tumour diffusely infiltrates surrounding tissue.…”

The Effect of Formalin Fixation on Resection Margins in Colorectal Cancer

“…This study demonstrated that formalin fixation caused slight muscle expansion and shrinkage of fatty tissue, which could affect the accuracy of tumor-free margin measurements. Significant shrinkage of tumorfree surgical margin after formalin fixation was noted in breast cancer specimens with a mean reduction of 10% in size, 14 while in renal tumors an overall shrinkage of 11.4% between fresh and histological specimens was observed. 18 To date, there have been 3 studies investigating the effect of formalin fixation on colorectal cancer specimens.…”

Involved margins after lumpectomy for breast cancer: Always to be re-excised?

“…Several other studies have showed that often residual cancer is not found on final pathology after re-excision for a positive margin [7-9, 14, 15]. In other words, a margin could be incorrectly considered positive after handling of the specimen for histopathological analysis, since the pathologist might misunderstand its interpretation due to specimen shrinkage [16,17]. Another point to be considered is the type of margin involvement.…”