- Occurrence of human pancreatic polypeptide in pancreatic endocrine tumors. Possible implication in the watery diarrhea syndrome. Larsson, L.I., Schwartz, T., Lundqvist, G., Chance, R.E., Sundler, F., Rehfeld, J.F., Grimelius, L., Fahrenkrug, J., Schaffalitzky de Muckadell, O., Moon, N. Am. J. Pathol. (1976)