Colorectal cancer

Positive results have been obtained from randomised controlled single or multicentre trials in patients with advanced colorectal cancer including those with stage II/III diseases48, 40-53. The results for both disease response and survival outcome in patients with colorectal or colon cancer receiving chemotherapy or radiation therapy with PSK are shown in (Table 3).

Table 3.   Randomised Controlled Trials for Colorectal Cancer

RefPatientsStageTreatmentOutcome
4855 cases
56 controls
Advance
(II/III)
1. Surgery + placebo
2. Surgery + PSK
(3gm/day for 2 months;
2g/day for 24 months;
1 gm/day thereafter)
8-yrs survival rate significant in the PSK group( p<0.05);
Disease-free interval
(p<0.05)
50Multicentre
221 cases
227 controls
1.Chemo
2.Chemo+ PSK
(3g/day for 3 years)
Disease-free interval and survival
significantly better for PSK in the colon group (p<0.05 in both)
51Total 207
134 cases
67 controls
6 withdrew
Primary
(II/III)
1. Chemo
2.Chemo+ PSK (3g per day for >2 yrs)
Overall survival rate higher in the PSK group but not significant (p=0.21).
3-year disease-free survival rate
significantly higher in the PSK group (p=0.02).
Stage III. Patients
3-year overall and disease-free survival rates in the PSK
significant (p=0.02; p =0.01)
52Total 205
137 cases
68 controls
Primary
(II/III)
All patients received
Mitomycin-C post-surgery.
1. Chemo
2. Chemo + PSK (3g/ day)
Both treatments for 2 yrs
5-year disease-free survival
significantly higher for PSK
(p<0.016)
5 –year overall survival rate difference (p <0.056).
Stage III patients: Overall and
5-year disease-free survival in PSK group (p <0.003; p<0.002).
53Colon cancer
with lymph
node
metastasis

Total 441
220 cases
221 controls
Dukes
A:7%
B:45.5%
C:47.3%
All patients received
chemo after surgery
for 3-4 weeks, then
10 courses of treatment.
1. PSK 4 weeks then 4 weeks chemo.
2. 4 weeks rest then 4 weeks chemo.
Seven- year survival rate
Significantly higher in the PSK group (p=0.019).
Overall survival or disease-free
rates not significant.

A recent meta-analysis of three centrally randomised controlled trials confirmed that adjuvant immunotherapy with PSK plus chemotherapy can improve both survival and disease-free survival of patients with curatively resected colorectal cancer compared with chemotherapy alone54. The overall survival risk ratio was 0.71 (95% CI:0.55-0.90; p <0.006) and the disease-free survival risk ratio was 0.72(95% CI:0.58-0.90); p <0.003).