Discussion
In this meta-analysis, F. nucleatum test showed better
discrimination ability for detecting 5-FU resistance in CRC patients as
compared with B. fragilis and E. coli . To the best of our
knowledge, ours is the first meta-analysis to assess the diagnostic
value of F. nucleatum , B. fragilis and E. coli test
for discriminating CRC patients with 5-FU-based regimen. The pooled DOR
was 4.92 (95% CI:2.23-7.33), indicating the test’s relatively high
discrimination ability. The pooled sensitivity and specificity were
64.9% and 69.6%, respectively, suggesting the test’s superior ability
for ruling out CRC patients which are not suitable for 5-FU-based
regimen. However, the PLR and NLR of the test was 2.57 (95%
CI:1.47-3.21) and 0.52 (95% CI:0.43-0.63), respectively, which shows
that CRC patients with 5-FU resistance have approximately 2.57 times
higher possibility of testing positive F. nucleatum compared with
subjects without 5-FU resistance, as well as 52% chance of an CRC
individual having 5-FU resistance if the test of F. nucleatum is
negative. The performance of the fecal F. nucleatum test in the
pooled PLR and NLR did not achieve the requirements of clinical
practice, and remains to be modified for clinical confirmation and
exclusion purposes. Nonetheless, the pooled results suggest that the
fecal F. nucleatum test has better discrimination ability thanB. fragilis and E. coli in clinical practice of suitable
5-FU-based therapy for CRC patients.
We identified the weaknesses of this study. First, the number of
patients and studies included were relatively small, which may affect
the overall quality of evidence. Second, these studies lacked a unified
criterion for F. nucleatum , B. fragilis and E. colipositive expression. Thus, larger-scale, multicenter and higher-quality
studies are required to confirm our findings in the future, allowing a
better comparison of analytical results of F. nucleatum on
clinical outcomes.
In conclusion, the fecal F. nucleatum test shows better
discrimination ability for detecting whether 5-FU-based regimen is
suitable for a colorectal cancer patient in our meta-analysis. We
certainly recognize that our suggested method is incomplete, mainly from
the limited sample size, but it is indicated that the fecal F.
nucleatum test represents at least a starting point toward non-invasive
and accurate procedures in the detection of 5-FU resistance for CRC
treatment.