Adjunctive imprint cytology of core needle biopsy specimens improved diagnostic accuracy for breast cancer

Possibility of avoiding axillary lymph node dissection by immune microenvironment monitoring in preoperative chemotherapy for breast cancer

Background

The diagnosis of metastasis by sentinel lymph node biopsy (SLNB) in early breast cancer surgery provides an accurate view of the state of metastases to the axillary lymph nodes, and it has now become the standard procedure. In the present study, whether omission of axillary lymph node dissection (ALND) after neoadjuvant chemotherapy (NAC) is possible by evaluation of tumor-infiltrating lymphocytes (TILs) before NAC in cases without metastasis on diagnostic imaging, but with metastasis on SLNB, was retrospectively investigated.

Methods

A total of 91 patients with resectable, early-stage breast cancer, diagnosed as cT1–2, N0, M0, underwent SLNB and were treated with NAC. A semi-quantitative evaluation of lymphocytes infiltrating the peritumoral stroma as TILs in biopsy specimens of primary tumors prior to treatment was conducted.

Results

In cases with a low number of TILs, estrogen receptor expression was significantly higher (p = 0.044), and human epidermal growth factor receptor 2 (HER2) expression was significantly lower than in other cases (p = 0.019). The number of TILs was significantly lower in cases in which the intrinsic subtype was hormone receptor-positive breast cancer (HRBC) (p = 0.044). Metastasis to axillary lymph nodes was significantly more common in HER2-negative cases and cases with a low number of TILs (p = 0.019, p = 0.005, respectively).

Conclusions

Even if macrometastases are found on SLNB in cN0 patients, it appears that ALND could be avoided after NAC in cases with a good immune tumor microenvironment of the primary tumor.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1692-3) contains supplementary material, which is available to authorized users.

Imprint cytopathology of core needle biopsies: a "first responder" role for cytotechnologists

INTRODUCTION

Imprint cytopathology (IC) of image-guided core needle biopsies (CNBs) is used to ensure adequate sampling. In our institution, cytotechnologists (CyTs) are the "first responders" for on-site adequacy assessment (OSAA) of image-guided CNBs. We report our experience with this expanded and relatively unexplored role for CyT.

MATERIALS AND METHODS

We reviewed all image-guided CNBs performed over a 12-month period that required OSAA. OSAA was provided primarily by CyT. Interpretation between all IC specimens and tissue diagnoses (concordance) and between adequate IC specimens and tissue diagnoses (accuracy) were analyzed. Performance was compared using the Fisher exact test. We retrospectively reviewed discrepant cases to deduce the reasons for discordance.

RESULTS

We evaluated 255 CNBs: 179 computed tomography-guided, 74 ultrasonography-guided, 2 endoscopy-guided. Lung (39%) followed by liver (16%) and lymph node (11%) were the most frequent sites of OSAA IC. Overall adequacy and accuracy rates were 80.8% and 87.9%, respectively, with a concordance rate of 81.2%. The performance for CyT alone, CyT/cytopathology fellow, and CyT/cytopathologist were comparable (P > 0.05). Review of discordant cases showed agreement with 91% of OSAA IC cases originally interpreted as inadequate, but with only 19% interpreted as adequate.

CONCLUSIONS

OSAA IC of CNBs expands the CyT's role in an effort to ensure adequate sampling. CyT performance was high in recognition of adequate versus inadequate IC slides when compared with the tissue. Reasons for discrepancy included sampling error and overinterpretation of atypia as being sufficient evidence of adequacy. Organ-specific cytologic criteria to assess adequacy are required to reduce interpretation error.