Re: Maternal inheritance pattern of hereditary pancreatitis in patients with pancreatic carcinoma.

Since our original report (1), we now have 412 patients in the International Hereditary Pancreatitis Registry. Sixteen patients have developed biopsyproven pancreatic cancer, with a parent of origin known for 11 patients—all paternal. Adding the two patients in the recent correspondence by Lerch et al. (2) makes 13 patients with a known parent of origin, of which 11 parents are paternal and two parents are maternal. Against an expected male-to-female parental distribution of 50 : 50, this is still statistically significant (P 4 .02). However, in our expanded database, we note that before 1960, when most of the pancreatic cancer patients were born, the male-to-female parent of origin ratio is 60 : 40, rather than 50 : 50. This slight difference may possibly be related to reduced fertility in females with hereditary pancreatitis married to normal males, compared with normal females married to males with hereditary pancreatitis. Similar fertility differences have been noted in females with much milder disorders (3). The probability of 11 paternal parents of origin against two maternal, if a 60 : 40 split is assumed, is about 0.06. We agree with Lerch et al. that hereditary pancreatitis patients with either a male or a female inheritance pattern are at risk for pancreatic cancer, but the risk appears to be higher in patients with a paternal inheritance pattern.