Effect of acupuncture therapy for postoperative gastrointestinal dysfunction in gastric and colorectal cancers: an umbrella review

Acupuncture is a centuries-old form of treatment that has been gaining increasing recognition in modern medicine, especially as a complementary therapy in the postoperative period. For patients undergoing gastric or colorectal cancer surgery, one of the most common challenges is the recovery of bowel function, which can take days or weeks to fully normalize. This problem, scientifically known as postoperative gastrointestinal dysfunction, affects between 10% and 56% of patients undergoing these surgeries, causing symptoms such as nausea, vomiting, abdominal distention, delayed passage of flatus, and difficulty with bowel movements. Beyond physical discomfort, this condition prolongs hospitalization, increases medical costs, and can significantly compromise patients' quality of life during the recovery period.

The study presented here represents a comprehensive and novel analysis of the efficacy of acupuncture in treating gastrointestinal dysfunction after gastric and colorectal cancer surgery. It is an umbrella review, a special type of research that examines multiple systematic reviews and meta-analyses already published on the same topic. The Chinese researchers searched eight international and Chinese scientific databases for all relevant studies published through July 2023, applying rigorous selection criteria. Only systematic reviews and meta-analyses that specifically evaluated the efficacy of different types of acupuncture in adult patients with confirmed gastric or colorectal cancer diagnoses who developed gastrointestinal dysfunction after surgery were included.

The intervention group had to receive some form of acupuncture, including manual acupuncture, electroacupuncture, moxibustion, auricular acupressure, transcutaneous electrical acupoint stimulation, and acupoint application, always in combination with standard care. The control group received only standard care or sham procedures.

The analysis revealed promising results for several acupuncture modalities. For patients with gastric cancer, auricular acupressure was effective in reducing time to first flatus passage by nearly 12 hours compared with standard care, while moxibustion was even more effective, shortening this time by approximately 19 hours. The warm needling technique reduced the time by about 13 hours, and manual acupuncture by 18 hours. Similar results were observed for time to first defecation, with moxibustion again demonstrating the best results, followed by warm needling and auricular acupressure.

For patients with colorectal cancer, combinations of different techniques proved particularly effective, with the combination of moxibustion and auricular acupressure standing out, significantly reducing both time to flatus passage and time to defecation. Electroacupuncture and acupoint application also demonstrated substantial benefits for these patients.

From a clinical standpoint, these results suggest that acupuncture may offer a safe and effective alternative to accelerate recovery of bowel function after cancer surgery. For patients, this potentially means fewer days of abdominal discomfort, faster return to normal feeding, and reduced hospitalization. Healthcare professionals may consider incorporating these techniques as part of a postoperative recovery protocol, especially given that acupuncture carries minimal risk when performed by qualified practitioners. The study identified that acupuncture works through multiple mechanisms, including vagal nerve stimulation, regulation of gastrointestinal hormones, and reduction of the inflammatory response caused by surgery.

These mechanisms help restore normal intestinal motility and accelerate the healing process.

It is important to recognize the limitations of this study, which impact interpretation of the results. The analysis included only six systematic reviews, all conducted in China, which may limit generalizability of the findings to other populations. The methodological quality of the included studies was rated low to very low in five of the six cases, mainly due to deficiencies in protocol registration, inadequate risk-of-bias assessment, and lack of evidence-quality analysis. Many of the original studies had problems with blinding implementation, which may have introduced bias into the results.

In addition, most of the outcomes assessed, such as time to flatus passage and defecation, depend in part on the subjective perception of patients and assessors, which can affect measurement accuracy. The study also did not evaluate the long-term effects of acupuncture nor directly compare the efficacy of the different techniques with each other.

Despite these limitations, this research represents an important step in the scientific recognition of acupuncture as a valid complementary treatment in the postoperative period. The results suggest that different acupuncture modalities can effectively accelerate recovery of gastrointestinal function after gastric and colorectal cancer surgery. However, the authors emphasize that these findings should be interpreted with caution, given the limited quality of available evidence. To strengthen these conclusions, more high-quality randomized clinical trials are needed, with larger samples, better blinding, and standardized outcome assessments.

It would also be valuable to develop specific protocols defining which type of acupuncture, frequency, and treatment duration are most beneficial for different patient profiles. This area of research continues to evolve and promises to offer new therapeutic options that may significantly improve the recovery experience of oncology patients.