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Zentralbl Chir 2024; 149(01): 75-82
DOI: 10.1055/a-2241-0334
DOI: 10.1055/a-2241-0334
Übersicht
Surveillance bei Watch-and-Wait nach neoadjuvanter Therapie beim Rektumkarzinom
Watch and Wait for Rectal Cancer
Zusammenfassung
Rund ein Drittel aller kolorektalen Karzinome (KRK) sind im Rektum lokalisiert. Im Rahmen eines multimodalen Therapiekonzeptes wird durch eine neoadjuvante Therapie in 50–60% der Fälle ein Downstaging des Tumors und in 10–30% der Fälle eine sog. Complete Clinical Response (cCR), definiert als klinisch (und radiologisch) nicht mehr detektierbarer Residualtumor nach Abschluss der neoadjuvanten Therapie, erzielt.
Vor dem Hintergrund perioperativer Morbidität und Mortalität einer radikalen Rektumresektion, mit u. a. Auftreten des Symptomkomplexes des sog. Low Anterior Resection Syndrome (LARS) sowie der zumindest passager gegebenen Notwendigkeit zur Deviation, wird die Frage nach einer Nutzen-Risiko-Abwägung einer Organresektion bei Vorliegen eines cCR aufgeworfen. In diesem Zusammenhang trat das therapeutische Konzept eines „Watch-and-Wait“-Vorgehens mit Unterlassung einer unmittelbaren Organresektion und Einschluss in ein strukturiertes Surveillance-Regime in den Vordergrund.
Zur sicheren, onkologischen Durchführung dieser Option ist es notwendig, Standards in der Definition einer geeigneten Patientenklientel sowie der Umsetzung des Konzepts zu erarbeiten. Dabei ist das inhärente Ziel neben der zunächst korrekten Selektion der Patientengruppe, die sich für ein primär nicht chirurgisches Vorgehen eignet, die frühzeitige und suffiziente Detektion eines Tumorwiederauftretens (sog. Local Regrowth) während der Phase des „Watch-and-Wait“ (Surveillance).
In diesem Zusammenhang adressieren wir in dieser Arbeit die Fragen: 1. nach dem optimalen Zeitpunkt des initiales Re-Stagings, 2. nach den Kriterien zur Beurteilung des klinischen Ansprechens und der Selektion der geeigneten Patientenklientel, 3. nach Rhythmus und Ausgestaltung des Surveillance-Protokolls.
Abstract
About one third of all colorectal carcinomas (CRC) are localised in the rectum. As part of a multimodal therapy concept, neoadjuvant therapy achieves downstaging of the tumour in 50–60% of cases and a so-called complete clinical response (cCR), defined as clinically (and radiologically) undetectable residual tumour after completion of neoadjuvant therapy, in 10–30% of cases.
In view of the perioperative morbidity and mortality associated with radical rectal resection, including the occurrence of a symptom complex known as low anterior resection syndrome (LARS) and the need for deviation, at least temporarily, the question of the risk-benefit balance of organ resection in the presence of cCR has been raised. In this context, the therapeutic concept of a “watch-and-wait” approach with omission of immediate organ resection and inclusion in a structured surveillance regime, has emerged.
For a safe, oncological implementation of this option, it is necessary to develop standards in the definition of a suitable patient clientele and the implementation of the concept. In addition to the initial correct selection of the patient group that is suitable for a primarily non-surgical procedure, the inherent goal is the early and sufficient detection of tumour recurrence (so-called local regrowth) during the “watch-and-wait” phase (surveillance).
In this context, in this paper we address the questions of: 1. the optimal timing of initial re-staging, 2. the criteria for assessing the clinical response and selecting the appropriate patient clientele, 3. the rhythm and design of the surveillance protocol.
Keywords
local regrowth - rectal carcinoma/cancer - rectum resection - survival - local regrowth - Watch-and-Wait - TNTPublication History
Received: 16 October 2023
Accepted after revision: 07 January 2024
Article published online:
05 March 2024
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