Chemo-Radiation After Surgery for Pancreatic Cancer May Prolong Survival

By Karla Gale

NEW YORK JUL 25, 2006 (Reuters Health) - Combining the use of gemcitabine with radiation therapy after surgical resection of pancreatic adenocarcinoma provides good local regional tumor control and may significantly improve survival, according to results of a phase II trial.

Surgery alone usually does not cure pancreatic cancer, Dr. A. William Blackstock and his colleagues note.  Previous research has demonstrated improved outcomes when radiation of the upper abdomen was combined with 5-fluorouracil-based chemotherapy. 

In the August issue of the British Journal of Cancer, Dr. Blackstock, from Wake Forest University School of Medicine in Winston-Salem, North Carolina, and his group propose that gemcitabine may be preferable because it possesses radiation-sensitizing properties. 

"Other studies showed that gemcitabine has more activity in patients with metastatic cancer," Dr. Blackstock told Reuters Health.  "Our notion was that if it is good for patients with metastatic cancer, let"s see if it is good for patients with curable disease."

The study included 46 patients who had undergone total pancreatectomy.  Ages ranged from 35 to 79 years, 73% were classified as having stage T3/T4 tumors, and 70% were lymph node positive. 

Patients with positive margins or whose surgery had been performed more than 8 weeks previously were excluded.  Dr. Blackstock explained, "You don"t want to treat patients who you don"t think will benefit.  If a patient has not recovered to baseline by 8 weeks, he or she will probably not be able to complete adjuvant therapy."

"Data suggest that patients with positive margins also have worse outcomes," he added.

Post-surgical treatment comprised IV gemcitabine 40 mg/m²/day, twice a week for 5 weeks, followed half an hour later with upper abdominal radiation (50.4 Gy in 5.5 weeks).  Patients whose disease was stable continued treatment with two cycles of gemcitabine, administered weekly for 3 weeks followed by a week without treatment.

Grade III or IV gastrointestinal or hematologic toxicities were infrequent, the authors note. 

Median survival was 18.3 months. Survival rates were 69% at 1 year and 24% at 3 years.  For patients whose tumors were classified as T1 or T2, median survival was 30.7 months, versus 14.6 months for higher stage cancer.

"A lot of studies looked at very early stage patients," Dr. Blackstock pointed out.  "In this series, many of the patients had very advanced disease, but despite their poor prognostic factors, survival was good."

He added:  "There is debate between European and US physicians regarding the role of radiation in the adjuvant setting.  We think these data support the safety of radiation in this setting, and that it has potential advantages for some patients."

SOURCE:

• Br J Cancer 2006.