title: Correlation of Ki-67 indices from biopsy and resection specimens of neuroendocrine tumours.
abstract: INTRODUCTION Neuroendocrine tumours (NETs) are a heterogeneous group of tumours with a highly variable presentation and prognosis. Management decisions are complex. Ki-67 levels in tissue samples are a key indicator used to grade tumours and guide treatment. This study assessed whether the Ki-67 index and tumour grade generated from tissue samples correlated with that assessed in resection specimens. METHODS This was a retrospective cohort analysis of all patients who had both a tissue sample and a resection specimen analysed in our trust, a tertiary referral centre, during 2012 and 2013. RESULTS Data from 36 patients were reviewed. Ki-67 indices from tissue samples and resection specimens showed strong correlation (r=0.95, p<0.001). Tumour grading was the same in the tissue sample and resection specimens for 22 patients (61.1%). In four patients (11.1%), the tissue sample overestimated the grade while in ten (27.8%), the sample underestimated the grade. CONCLUSIONS In most cases, the Ki-67 index and tumour grade from the tissue sample matched that of the resection specimen. However, in nearly 40% of cases, the tissue sample grading did not match the resection tumour grading. In the majority of these, the tissue sample underestimated disease activity. A low Ki-67 index in a tissue sample should therefore be taken as provisional and should not, in isolation, persuade clinicians to choose a more conservative treatment approach if there is clinical, biochemical or radiological evidence suggestive of a more aggressive disease pathology.
authors.affiliation: Newcastle upon Tyne Hospitals NHS Foundation Trust , UK.
authors.forename: J
authors.initials: J
authors.lastname: Barnes
authors.affiliation: Newcastle upon Tyne Hospitals NHS Foundation Trust , UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Johnson
authors.affiliation: Newcastle upon Tyne Hospitals NHS Foundation Trust , UK.
authors.forename: J J
authors.initials: JJ
authors.lastname: French
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D062005:Biopsy, Large-Core Needle; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D004067:Digestive System Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007078:Ileal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D019394:Ki-67 Antigen / Q000378:metabolism*; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D018358:Neuroendocrine Tumors / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D011379:Prognosis; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery
chemical_list: D019394:Ki-67 Antigen
keywords: Diagnostic techniques and procedures; General surgery; Ki-67; Neuroendocrine tumours; Pathology