Background:After achieving a clinical complete response through neoadjuvant
chemoradiotherapy, a nonoperative management approach for rectal cancer
patients known as Wait and Watch (W&W) has gained increasing attention.
However, the W&W strategy has been related to higher local recurrence
and ambiguous long-term survival. This meta-analysis compared key prognosis
indicators between W&W and surgical treatment in an effort to clarify
some long-standing points of confusion.Methods:Pubmed, Web of Science, EMbase, Cochrane Library were searched for relevant
researches comparing W&W with surgery treatment, with a time criteria
set from 1 January 2002 to 4 July 2019. Endpoints were 2-year local
regrowth/recurrence, 2-year distant metastasis (plus local
regrowth/recurrence), 3- and 5-year disease-free survival (DFS), and overall
survival (OS).Results:In total, nine studies with 801 patients were enrolled, of which 348 were
managed by W&W and 453 by surgery. Surgery patients were further divided
into a pathological complete response (pCR) group (all included patients
achieved pCR) and a surgery group (consisting of both pCR and non-pCR
patients without deliberate screening). Compared with the surgery group,
W&W patients have higher 3- and 5-year OS, and are not inferior on
2-year local regrowth (LR), 2-year distant metastasis (DM)/DM+LR, and 3- and
5-year DFS. On the other hand, compared with the pCR group, the W&W
group is inferior on 2-year LR, 3- and 5-year DFS, and 5-year OS, and not
inferior on 2-year DM/DM+LR and 3-year OS.Conclusions:In contrast with patients undergoing surgical treatment, the W&W group
has higher 3- and 5-year OS, and is not inferior on other major prognostic
indicators, which, however, is based on the fact that the tumor stage in the
W&W group is generally earlier. Versus surgically
treated patients who acquired pCR, W&W group is inferior on all major
prognostic indicators except 2-year DM/DM+LR and 3-year OS. Additionally, by
comparison of cCR definitions across different studies, we conclude that
implementation of the strictest cCR criteria is critical for W&W
patients to acquire maximum prognostic benefit.