The persistent controversy over which treatment is the one with the best patient outcome for postoperative pancreatic cancer patients may finally have been settled by a research team at the Institute of Epidemiology and Preventive Medicine of National Taiwan University’s College of Public Health.
Pancreatic cancer has been called a silent killer because symptoms rarely occur at the early stage of the disease and, as one of the fastest-spreading cancers, its five-year survival rate is less than 5 percent — the worst survival rate of all cancers.
As 80 percent of pancreatic cancer patients suffer from recurrence, several postoperative adjuvant treatments have been attempted to lower the risk of recurrence. They include taking a single chemotherapy drug — fluorouracil or gemcitabine — undergoing radiation therapy, or having radiation plus fluorouracil or gemcitabine.
Liao Wei-chih (廖偉智), attending physician of internal medicine at NTU Hospital and one of the coauthors of the research article recently published in the medical journal the Lancet Oncology, said that for the past 10 years there has been little consensus on the optimum postoperative adjuvant treatment for resected pancreatic adenocarcinoma, and the contribution of this research is to offer common ground for resolving the debate.
The debate harkens back to the difference in opinion between US and European medical experts on the effectiveness of radiation therapy, Liao said.
“While in the US radiation treatment is the standard of care [to be given along with chemotherapy], in Europe radiation therapy is considered ineffective and potentially harmful,” Liao added.
With the two major fields holding conflicting views, relevant studies undertaken according to respective directives had been inconclusive in terms of providing a guideline for the optimum treatment, as direct comparisons between certain treatments were not possible.
“The analysis method used by the team has made comparisons that were previously unattainable possible,” NTUH internal medicine attending physician and article coauthor Lin Jaw-town (林肇堂) said.
The analysis method used is called Bayesian network meta-analysis, also known as mixed treatment comparison.
“To put it simply, it allows the comparison among treatments A, B and C when [the data at hand are from those] past studies comparing only A with B or B with C,” associate professor of biostatistics Tu Yu-kang (杜裕康) said.
Using the analysis method, the research team found that “chemotherapy with fluorouracil or gemcitabine is the optimum postoperative adjuvant treatment for pancreatic cancer and reduces mortality after surgery by about a third” relative to observation, or no adjuvant treatment, after surgery.
“Radiation treatment plus chemotherapy is less effective in prolonging survival than chemotherapy,” Liao said.
“And it causes more serious side effects as well,” Tu added.