After colorectal cancer surgery, the unexpected factor that shaped recurrence — the power of “one year of herbal medicine,” confirmed in a joint study with Memorial Sloan Kettering Cancer Center

Even after being diagnosed with stage II or III colorectal cancer (CRC), having the tumor removed by surgery, and completing chemotherapy, patients still carry a constant fear.

“What if it comes back?”

Even patients diagnosed at stage II or III who received the same surgery and the same chemotherapy can end up with different results five years later. What makes that difference?

In a study conducted jointly by Memorial Sloan Kettering Cancer Center in the USA and a major cancer hospital in Beijing, herbal medicine treatment was the factor that set those outcomes apart.

The powerful effect of herbal medicine, confirmed together with a world-leading cancer center

The paper introduced today carries great significance in that Memorial Sloan Kettering Cancer Center in the USA — one of the world’s top three cancer centers — took part as a joint research team to prospectively verify “what benefit there is when herbal medicine is added to standard treatment.”

What happened to those who took it for more than a year

The researchers defined patients who took herbal medicine (decoctions) tailored to their own physical condition for 12 months or more after surgery as the “high-exposure” group. Of the 312 patients, 166 (53.2%) fell into this category.

After adjusting for various factors, the high-exposure group had a 38% lower risk of recurrence or death for disease-free survival (DFS) (hazard ratio 0.62, 95% confidence interval 0.39–0.98), and for overall survival (OS) the risk of death was a remarkable 69% lower (hazard ratio 0.31, 95% confidence interval 0.14–0.68). This difference was especially pronounced in patients who received chemotherapy.

Put simply, among patients who started from the same conditions, those who continued herbal medicine for more than a year had markedly fewer recurrences and deaths.

The key lay in the “duration of use”

What is interesting is that this study used “duration of use” — that is, “duration of exposure” — as its criterion. It was not a brief course taken right after surgery and then stopped; continuing steadily for at least a year is what set the outcomes apart. In cancer treatment, surgery and chemotherapy end within a set period, but the risk of recurrence lingers long afterward. The point is that herbal medicine mattered only when kept close throughout that long recovery period.

Another condition — being “personalized”

That herbal medicine was not the same prescription for everyone. What was used in the study was based on syndrome differentiation (辨證, syndrome differentiation) — that is, an individual prescription matched to each person’s body by examining their symptoms and the state of the tongue and pulse. The broad direction of the prescriptions was to strengthen the energy of the spleen (脾) and kidney (腎), soothe the liver’s energy (soothing the liver, 疏肝), and promote blood circulation to disperse stagnation (activating blood and resolving stasis, 活血祛瘀). The key is that these were results from prescriptions attuned to the individual — not a single standardized pill — continued for more than a year.

In summary

What this study says is clear. In stage II and III colorectal cancer, patients who diligently received standard treatment and then steadily continued herbal medicine matched to themselves for more than a year showed markedly better outcomes in both recurrence and mortality risk.

Of course, herbal medicine does not replace standard treatments such as surgery, chemotherapy, or radiation. All of the benefits in this study, too, were added on top of standard treatment. If you are facing colorectal cancer surgery, or have already completed surgery and chemotherapy and entered the recovery period, we recommend deciding on herbal medicine suited to you after thorough consultation with a specialist Korean medicine doctor. The core message this study offers ultimately comes down to two things: a “personalized herbal prescription” and “consistent use.”