The use of personalized biomarkers and liquid biopsies to monitor treatment response and disease recurrence in locally advanced rectal cancer after neoadjuvant chemoradiation

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is the mainstay treatment for locally advanced rectal cancer. Variable degrees of tumor regression are observed after nCRT and alternative treatment strategies, including close surveillance without immediate surgery, have been investigated to spare patients with complete tumor regression from potentially adverse outcomes of radical surgery. However, clinical and radiological assessment of response does not allow accurate identification of patients with complete response. In addition, surveillance for recurrence is similarly important for these patients, as early detection of recurrence allows salvage resections and adjuvant interventions. We report the use of liquid biopsies and personalized biomarkers for monitoring treatment response to nCRT and detecting residual disease and recurrence in patients with rectal cancer. We sequenced the whole-genome of four rectal tumors to identify patient-specific chromosomal rearrangements that were used to monitor circulating tumor DNA (ctDNA) in liquid biopsies collected at diagnosis and during nCRT and follow-up. We compared ctDNA levels to clinical, radiological and pathological response to nCRT. Our results indicate that personalized biomarkers and liquid biopsies may not be sensitive for the detection of microscopic residual disease. However, it can be efficiently used to monitor treatment response to nCRT and detect disease recurrence, preceding increases in CEA levels and radiological diagnosis. Similar good results were observed when assessing tumor response to systemic therapy and disease progression. Our study supports the use of personalized biomarkers and liquid biopsies to tailor the management of rectal cancer patients, however, replication in a larger cohort is necessary to introduce this strategy into clinical practice.     

Timing and nature of reconstructive surgery for disorders of sex development – Introduction

The ideal timing and nature of surgical reconstruction in individuals with Disorders of Sex Development (DSD) is highly controversial. Despite the increasing number of publications on this topic, evidence-based recommendations still cannot be made. However it is generally accepted that optimal care for DSD requires an experienced multidisciplinary team. This means that surgical decisions are now made within the context of a multidisciplinary team and all members of the team – and not just specialist surgeons – may be called upon to discuss choices for surgery with patients and parents. To do this well, every clinician in the team should have an understanding of the range of techniques available for genital surgery, the risks and benefits of procedures and the controversies surrounding timing of surgery.The aim of this paper is to give an overview of the variety of surgical procedures in current use and in what situation a particular technique would be indicated. The short-term risks and benefits are described and where available long-term outcome data is discussed. To date, discussions surrounding genital surgery have been led primarily by surgeons. Some non-surgical clinicians have expressed unease about decision making in genital surgery but have felt ill equipped to comment on an area with which they are unfamiliar. This review gives a detailed explanation of current surgical practice offered in a specialized center for DSD and such information should facilitate a more balanced discussion.