Crescentini, F.; Deutsch, F.; Sobrado, C. W.; Araújo, S. de. Umbilical Mass As the Sole Presenting Symptom of Pancreatic Cancer: A Case Report . Rev. Hosp. Clín. 2004, 59 (4), 198-202. https://doi.org/10.1590/S0041-87812004000400008.