Grading of breast cancer on needle core biopsy: does a reduction in mitotic count threshold improve agreement with grade on excised specimens?

BACKGROUND: Accurate assessment of invasive breast cancer grade on needle core biopsy (NCB) is important as it guides treatment. AIM: To assess the agreement between grade of invasive cancer on NCB and excision and determine whether altering the mitotic count score threshold on NCB improves it. METHODS: Pathology slides from patients with an NCB diagnosis of invasive breast cancer who underwent subsequent breast conservation surgery in 2012 were reviewed. Mitotic counts were assessed and tumour grade agreement between NCB and excision evaluated. The mitotic count thresholds were altered and grade agreement was reassessed. RESULTS: In 283/359 (79%) cases, there was concurrence on histological grade between NCB and excision. Reduction in mitotic count thresholds did not improve either overall tumour grade agreement or agreement within any subgroup of patients. CONCLUSIONS: In our experience, the current mitotic count score thresholds are appropriate and should be maintained.

Histological evaluation of preoperative mediastinoscopy lymph node biopsies in non-small cell lung cancer.

INTRODUCTION: Despite the advent of PET scanning and endoscopic minimally invasive methods of sampling mediastinal lymph nodes, surgical assessment, particularly by mediastinoscopy, remains an important tool for staging non-small cell lung cancer. METHODS: We carried out a retrospective review of mediastinoscopic lymph node biopsies taken at The Royal Infirmary of Edinburgh between 1996 and 2006 and performed additional histological investigations on select cases. RESULTS: In total, 89/802 (11%) patients had a negative mediastinoscopy but final resection stage of N2/N3. Within this group, 41/89 (46%) patients had positive resection lymph nodes in stations potentially accessible to biopsy at mediastinoscopy. Of these, 30 (34%) patients had had the metastatic station sampled at mediastinoscopy. Further histopathological examination (multiple levels and pancytokeratin immunohistochemistry) of these original biopsies detected micrometastases in two cases, one of which, in retrospect, had been missed on the original section at the time of reporting. Isolated tumour cells were detected by immunohistochemistry in another two cases. CONCLUSIONS: Routine examination of additional levels and immunohistochemical staining of mediastinal lymph nodes biopsies is not required and would not improve the overall negative predictive value of the procedure.