Utility of intraoperative frozen section examination of sentinel lymph nodes in ductal carcinoma in situ of the breast

Is the frozen section examination for sentinel lymph node necessary in early breast cancer patients?

PURPOSE

Sentinel lymph node (SLN) biopsy (SLNB) is widely performed for axillary staging in patients with breast cancer. Based on the results of frozen section examination (FSE), surgeons can decide to continue further axillary dissections. This study aimed to verify the accuracy of FSE for SLNs.

METHODS

We reviewed the records of 4,219 patients who underwent SLNB for primary invasive breast cancer between 2007 and 2016 at the Severance Hospital. We evaluated factors associated with the false-negative results of FSE for SLNs using the Generalized Estimating Equations model.

RESULTS

A total of 1,397 SLNs from 908 patients were confirmed to be metastatic. Seventy-one patients (1.7%) had confirmed pathologic N2 or N3 stage. Among metastatic SLNs, micrometastasis was found in 234 (16.8%). The overall accuracy of SLNB was 98.5%. The sensitivity and false-negative rate of FSE were 86.4% and 13.6%, respectively. Several clinicopathological factors, including the size of SLN metastases, suspicious preoperative axillary lymph nodes, and luminal B subtype, were associated with a higher rate of false-negative results.

CONCLUSION

Most patients were not indicated for axillary lymph node dissection. Some patients may show transition in their permanent pathology due to the size of the metastatic node. However, the false-negative results of FSE for SLNs based on the size of the metastatic node did not change our practice. Therefore, intraoperative FSE for SLN should not be routinely performed for all breast cancer patients.

Minimal Clinical Impact of Intraoperative Examination of Sentinel Lymph Nodes in Patients With Ductal Carcinoma In Situ: An Opportunity for Improved Resource Utilization

OBJECTIVES

There is little information regarding sentinel lymph node (SLN) frozen-section examination in patients with a history of ductal carcinoma in situ (DCIS). We evaluated the usage, clinical impact, and pathology resources used for SLN cryosectioning in mastectomy cases with a DCIS history.

METHODS

Mastectomies with SLNs submitted from 2012 to 2013 at a tertiary care center were analyzed. Medicare reimbursement was used to estimate pathology health care expenditures of intraoperative frozen sections.

RESULTS

There was no difference in the rate of SLN frozen-section examination or parts submitted, total blocks frozen, total blocks submitted, or total SLNs identified per case between the DCIS (n = 139) and invasive (n = 369) groups. Nine patients with DCIS had SLN metastases (three macrometastases, two micrometastases, and four isolated tumor cells), all of which were examined by frozen section. Only the macrometastases were identified by cryosectioning, which led to two synchronous axillary lymph node dissections that did not yield any additional positive nodes. A total of $19,313 was spent for pathology per DCIS patient with surgical management affected, whereas only $1,019 was spent per invasive carcinoma patient affected.

CONCLUSIONS

Decreasing SLN frozen-section use in patients with a history of DCIS represents an opportunity for pathology cost containment.

Is sentinel lymph node biopsy indicated in patients with a diagnosis of ductal carcinoma in situ? A systematic literature review and meta-analysis

BACKGROUND

Recent discussion has suggested that some cases of ductal carcinoma in situ (DCIS) with high risk of invasive disease may require sentinel lymph node biopsy (SLNB).

METHODS

Systematic literature review identified 48 studies (9,803 DCIS patients who underwent SLNB). Separate analyses for patients diagnosed preoperatively by core sampling and patients diagnosed postoperatively by specimen pathology were conducted to determine the percentage of patients with axillary nodal involvement. Patient factors were analyzed for associations with risk of nodal involvement.

RESULTS

The mean percentage of positive SLNBs was higher in the preoperative group (5.95% vs 3.02%; P = .0201). Meta-regression analysis showed a direct association with tumor size (P = .0333) and grade (P = .00839) but not median age nor tumor upstage rate.

CONCLUSIONS

The SLNB should be routinely considered in patients with large (>2 cm) high-grade DCIS after a careful multidisciplinary discussion. In the context of breast conserving surgery, the SLNB is not routinely indicated for low- and intermediate-grade DCIS, high-grade DCIS smaller than 2 cm, or pure DCIS diagnosed by definitive surgical excision.

Intraoperative optical coherence tomography for assessing human lymph nodes for metastatic cancer

Background

Evaluation of lymph node (LN) status is an important factor for detecting metastasis and thereby staging breast cancer. Currently utilized clinical techniques involve the surgical disruption and resection of lymphatic structure, whether nodes or axillary contents, for histological examination. While reasonably effective at detection of macrometastasis, the majority of the resected lymph nodes are histologically negative. Improvements need to be made to better detect micrometastasis, minimize or eliminate lymphatic disruption complications, and provide immediate and accurate intraoperative feedback for in vivo cancer staging to better guide surgery.

Methods

We evaluated the use of optical coherence tomography (OCT), a high-resolution, real-time, label-free imaging modality for the intraoperative assessment of human LNs for metastatic disease in patients with breast cancer. We assessed the sensitivity and specificity of double-blinded trained readers who analyzed intraoperative OCT LN images for presence of metastatic disease, using co-registered post-operative histopathology as the gold standard.

Results

Our results suggest that intraoperative OCT examination of LNs is an appropriate real-time, label-free, non-destructive alternative to frozen-section analysis, potentially offering faster interpretation and results to empower superior intraoperative decision-making.

Conclusions

Intraoperative OCT has strong potential to supplement current post-operative histopathology with real-time in situ assessment of LNs to preserve both non-cancerous nodes and their lymphatic vessels, and thus reduce the associated risks and complications from surgical disruption of lymphoid structures following biopsy.