Abstract 3291
Background
Microsatellite instability (MSI) is thought to be a marker of immunogenicity and better prognosis in colorectal cancer (CRC). However, the mechanism by which MSI confers a survival advantage is not well known and there is a range of results reported in the literature.
Methods
A systematic literature search of original studies was performed on Ovid searching Medline, Embase, Cochrane Library, CINAHL, Clinical Trials databases from inception of database to current. Data extracted included age, stage, MSI-H, MSS and MSI-L, proximal (right) vs. distal (left), colon vs. rectal, BRAF status, type of MSI or IHC test used, incidence of Lynch within cohort. The primary endpoint was survival (overall survival (OS), disease/relapse free survival (DFS) and disease (cancer) specific survival DSS). Statistical analysis was performed using RevMan Ver 5.3 Cochrane Collaboration.
Results
From 11,747 studies, 117 met the inclusion criteria (n = 100,257; MSI-H n = 12,263, (MSI-H 12.2%). Overall, MSI was associated with improved OS (OR 0.80 (0.71, 0.91). When stratified by stage, there was no difference in OS in stage I and IV, but a protective effect in stage II (OR 0.69 (0.51, 0.92)) and III (0.70 (0.54, 0.91)) CRC. By age, there was benefit in studies where reported median age < 60 (OR 0.66 (0.54,0.82)) but not ≥ 60. There was no difference in OS between MSI-L and MSS. In studies including only mucinous/signet cell/poor differentiation, there was no difference in OS. In both right and left colon, MSI status was associated with improved OS, but not in the rectum. MSI status was associated with improved DFS (HR 0.75 (0.66, 0.84)), but there was no difference in DSS (HR 0.78 (0.60, 1.03)), and this was seen in all stages (I-IV).
Conclusions
MSI is associated with improved overall survival in stage II and III colorectal cancer. Improved prognosis is seen in younger patients, in both right and left sided colon cancer, but evidence is limited in rectal cancer. MSI was associated with less relapse, but was not associated with cancer specific survival at any stage.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5458 - Baseline characteristics from CLARINET FORTE: Evaluating lanreotide autogel (LAN) 120 mg every 14 days in patients with progressive pancreatic or midgut neuroendocrine tumours during a standard first-line LAN regimen.
Presenter: Philippe Ruszniewski
Session: Poster Display session 2
Resources:
Abstract
1234 - Analysis of PD-1/PD-L1 blockade biomarker and immune infiltrates in Gastroenteropancreatic neuroendocrine carcinoma
Presenter: Jia Zhang Xing
Session: Poster Display session 2
Resources:
Abstract
1517 - Diabetes Is Associated With Pancreatic Neuroendocrine Tumors Growth and Metastasis
Presenter: Zhiyao Fan
Session: Poster Display session 2
Resources:
Abstract
2145 - Investigation of the reclassification of G1/G2 pancreatic neuroendocrine neoplasms by WHO 2017 classification
Presenter: Takahiro Yokose
Session: Poster Display session 2
Resources:
Abstract
3134 - Treatment with somatostatin analogues after radiopeptide therapy
Presenter: Daria Handkiewicz Junak
Session: Poster Display session 2
Resources:
Abstract
2191 - Safety and Tolerability of Surufatinib in Western Patients with Solid Tumors
Presenter: Erika Hamilton
Session: Poster Display session 2
Resources:
Abstract
3253 - The impact of tumour absorbed dosimetry with survival outcomes after peptide receptor radionuclide therapy in metastatic neuroendocrine tumours.
Presenter: Rahul Ladwa
Session: Poster Display session 2
Resources:
Abstract
3581 - Opportunist and Serious Infections in Patients with Neuroendocrine Tumors Treated With Everolimus: A Multicenter Study of Real World Patients
Presenter: Carine Mauro
Session: Poster Display session 2
Resources:
Abstract
5374 - Establishment of Prognostic Nomogram Based on the Metastatic Lymph Nodes Ratio for Patients with Gastric Neuroendocrine Tumour
Presenter: yaobin lin
Session: Poster Display session 2
Resources:
Abstract
3951 - Neutrophil-lymphocyte ratio as an independent predictive factor in Neuroendocrine Neoplasms
Presenter: Sofia Ferreira
Session: Poster Display session 2
Resources:
Abstract