What Is the Correct Procedure for Evaluating a pCR?

  • N. Scott


Over the past 15–20 years, it has become commonplace for surgery to be performed after a course of preoperative radiotherapy with or without concomitant chemotherapy. This has mainly taken the form of either short-course radiotherapy (SCRT) administered over 5 days followed by resection a week later or chemoradiotherapy (CRT) given over several weeks with a delay of 6–8 weeks before operation. Recently there have been attempts to incorporate more intense systemic chemotherapy into neoadjuvant treatments, either during an extended gap between SCRT and surgery (SCRT plus delay) or even by omitting radiation entirely. While some tumours show little response to these schedules, others demonstrate a range of morphological and biological changes, which in a minority of cases results in complete tumour disappearance. This is commonly referred to as a pathological complete response, i.e. pCR. In this chapter I will outline some of the pathological changes which occur following radiotherapy and chemotherapy, describe the current approach to their examination and interpretation and highlight any areas of uncertainty where evidence is incomplete or conflicting.


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© Springer-Verlag Berlin Heidelberg 2018

Authors and Affiliations

  1. 1.Department of HistopathologyLeeds Teaching Hospitals NHS TrustLeedsUK

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