REFILE-Conservative management may be best for most pancreatic serous cystic neoplasms

Last Updated: 2015-07-01

(Replaces 2nd sentence of para 6 with a corrected sentence.)

By Lorraine L. Janeczko

NEW YORK (Reuters Health) - Most patients with serous cystic neoplasm (SCN) of the pancreas should be managed conservatively, according to results of a new multinational study.

"This study suggests that SCN is almost always a benign and indolent tumor, seldom symptomatic, with slow growth and very low risk of new onset symptoms including malignant progression," the study authors said.

"Surgical treatment should be proposed in a minority of patients, only for uncertain diagnosis remaining after complete workup including CT (computed tomography) scan, MRI (magnetic resonance imaging), and EUS (endoscopic ultrasonography), significant and related symptoms or exceptionally when concern with malignancy exists," they advised.

Lead study author Dr. Benedicte Jais, of the Department of Gastroenterology and Pancreatology of Beaujon Hospital, Clichy, France, and colleagues described the poorly understood natural history of SCN in an article online June 4 in Gut.

The researchers conducted a retrospective multinational study of 2622 patients diagnosed with SCN between 1990 and 2014. They ranged in age at diagnosis from 16 to 99 with a median age of 58, and 74% of patients were female. Overall, 27% of patients reported nonspecific abdominal pain, 9% had pancreaticobiliary symptoms, 5% had diabetes mellitus and 4% had other symptoms, and 61% were asymptomatic.

The overall initial median cyst diameter was 31 mm. During the first year after diagnosis, 52% of patients had surgery. One year or more after diagnosis, another 9% had resection; the remaining 39% had no surgery.

Tumor growth correlated with initial tumor size (correlation coefficient=0.211; p<0.001). The 976 tumors smaller than 4 cm grew more slowly than the 295 that were 4 cm or larger (1.25 vs 2.7 mm per year, p=0.002). Tumor growth was not associated with age or radiology pattern.

Surgical indications included: uncertain diagnosis in 60%, symptoms in 23%, size increase in 12%, large size in 6%, and adjacent organ compression in 5%. Among the 1271 patients followed longer than 1 year, tumor size increased in 37%, with a growth rate of 4 mm per year. Growth rate was stable in 57% of patients and decreased in 6%. The researchers found three serous cystadenocarcinomas. Overall, 10 (0.6%) patients died after surgery, including one (0.1%) whose death was related to SCN.

After three years, clinically relevant symptoms occurred in a very small proportion of patients and size slowly increased in fewer than one-half of them.

Guidelines advise that SCN be resected in patients with disabling symptoms or when the cyst diagnosis is uncertain.

"Pancreatectomies are still associated with high morbidity and mortality. Avoiding this operation when it is not necessary benefits patients. This study shows by data what we had always suspected: most small asymptomatic lesions do not progress on observation and do not require resection," wrote Dr. Yuman Fong, chair of the Department of Surgery at City of Hope Comprehensive Cancer Center in Duarte, California, in an email to Reuters Health.

"Current generation cross-sectional imaging can accurately diagnose SCN of the pancreas," wrote Dr. Fong, who was not involved in the study. "We used to operate on many SCNs only because we could not tell the diagnosis by imaging."

Dr. Fong said that questions remaining about SCN treatment include, "when should we perform endoscopic diagnostic or palliative intervention? The fact that one of the patients in this study died from aspiration during ERCP puts an emphasis on potential risks of endoscopy."

"I hope this large multicenter study will encourage observation as a more common choice of action in this benign disease," he added.

The corresponding author did not respond to requests for comments.

Two authors declared financial relationships with Boston Scientific, or Abbvie and Mayoly Spindler. Dr. Fong said that he had no conflicts of interests with the study.

SOURCE: http://bit.ly/1BUJRlA

Gut 2015.