Increased Survival in Metastatic Pancreatic Cancer

Treatment and survival rates for stage IV pancreatic cancer (ie, metastatic pancreatic cancer or MPC) have gone up during in the past 10 years, according to the results of a VA study published in the Journal of Gastrointestinal Oncology. The advent of new anti-neoplastic agents has boosted survival.

“Despite the benefits of treatment, undertreatment of MPC remains an ongoing area of concern within the GI oncology community,” wrote authors, led by Ibrahim Azar, MD, Department of Internal Medicine, Albany Medical Center, Albany.

In the current retrospective study, nationwide data were mined from the National Veterans Affairs Cancer Cube Registry for 6,775 patients (97.44% men; 39.39% aged over 70 years; 38.02% aged 60-70 years) who were diagnosed with metastatic pancreatic cancer between 2000 and 2014. American College of Surgeons’ (ACS) Committee on Cancer (CoC) accreditation was taken from the ACS website.

According to results of the study, MPC makes up 52.31% of all pancreatic cancers diagnosed. The share of early-onset pancreatic cancer (EOPC) was 2.84%. Per the authors, EOPC may be underrepresented because the study population skewed older.

Versus all stages of pancreatic cancer, stage IV pancreatic cancer had a lower proportion of cancer originating from the head of the pancreas (39.33% vs 50.63%) and a greater proportion originating from the tail (17.99% vs 13.39%). Of importance, tumors originating from the head of the pancreas are at greater risk of leading to biliary symptoms and thus are more likely to be detected at an earlier stage.

Overall, treatment rate in the VA at the national level with first-line chemotherapy was 37.61%, with the rate of treatment over the study period rising from 33.01% in 2000 to 41.95% in 2014. This linear increase in treatment rate translated into an increase of 1–5 years survival from 9.29% in 2000 to 22.99% in 2014. Furthermore, 5–10 years survival rates went up from 0.96% in 2000 to 6.00% in 2012.

Treatment rates in CoC-accredited vs non-CoC accredited VA hospitals were comparable (38.94% and 38.12%, respectively). Moreover, survival rates in CoC-accredited and non-COC accredited VAs were also comparable, with a 1–5 years survival rate of 8.89% and 8.57%, respectively.

In the United States, the incidence of pancreatic cancer grew from 1999 to 2008-possibly secondary to increasing rates of obesity and an aging population. However, disease mortality went mostly unchanged, with overall 1-year survival equal to 18% and 5-year survival equal to fewer than 5%.

Clinical staging of pancreatic cancer focuses on resectability, with surgical resection being a key consideration in the treatment of early pancreatic cancer. Staging runs the gamut from resectable, to borderline resectable, locally advanced unresectable, and metastatic. Chemotherapy is recommended in all stages of pancreatic cancer and the cornerstone of treatment for metastatic disease.

Historically, the only available treatment for late-stage disease was gemcitabine. Recent trials, however, have demonstrated multiple gemcitabine combinations as well as FOLFIRINOX have been effective in increasing median survival by several months, while decreasing impairment of quality of life.

A 1996 review of the National Cancer Database uncovered that only 35% of patients with MPC received chemotherapy; whereas, by 2016, estimates rose to a mere 50%. Moreover such undertreatment is not only a U.S. problem, with one Canadian study showing that only about one-third of patients with MPC completing referrals to a medical oncologist.
Current NCCN guidelines recommend that clinical decision-making concerning diagnostic management and resectability include multidisciplinary teams at high-volume healthcare centers.

“The ACoS CoC accreditation of VA hospitals is not associated with a change in treatment or survival rates of MPC. This likely reflects the high degree of uniformity and conformity of standards of care amongst VA hospitals,” concluded the authors.