Published in:
01-02-2012 | Original Article
Colonic methanogenesis in vivo and in vitro and fecal pH after resection of colorectal cancer and in healthy intact colon
Authors:
Reetta Holma, Pia Osterlund, Ulla Sairanen, Mikko Blom, Merja Rautio, Riitta Korpela
Published in:
International Journal of Colorectal Disease
|
Issue 2/2012
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Abstract
Purpose
We compared colonic methanogenesis in vivo and in vitro as well as fecal pH in healthy subjects and in patients with resected colorectal cancer thus without the possible confounding effects of the tumor.
Methods
A total of 144 subjects, 96 with resected colorectal cancer (of whom, 48 were with metastatic disease), 48 healthy subjects with intact colon, were analyzed for breath methane, fecal methanogenesis in vitro and fecal pH. In addition, the association between methanogenesis and pH with cancer site, operation technique and abdominal discomfort was investigated.
Results
In vivo and in vitro methane measurements were in agreement. The percentage of breath methane excretors and fecal pH did not significantly differ in participants resected for colorectal cancer, either with (46%, 6.76) or without (46%, 6.77) metastatic disease, from healthy participants (40%, 6.80). Breath methane excretors had higher fecal pH than nonexcretors (7.05 versus 6.57, P < 0.001) and less abdominal discomfort (30% versus 54%, P = 0.016). Among patients with resected right-sided cancer (n = 15), there were less breath methane excretors (20%) than among those with resected left-sided cancer (51%, n = 81, P = 0.029) as well as lower fecal pH than among those with resected left-sided cancer (6.27 versus 6.86, P = 0.002) and among healthy subjects (6.80, P = 0.010).
Conclusions
Patients with resected colorectal cancer were as frequently methane producers as healthy subjects with intact colon, and there was no difference in their fecal pH. Low methanogenesis was found in patients with abdominal discomfort and is a possible characteristic, along with low fecal pH, to right-sided colorectal cancer.