De Cassan was a financier and fought during World War II in the German military.[1]
He participated in the demonstration event, military patrol (precursor to biathlon), in the 1948 Winter Olympics, when he had the military rank Caporalmaggiore.[2] In 1948 he placed first, 1950 second and in 1951 he finished first again at the Italian masterships of cross-country skiing in the 50 km (and long distances) category.[3]
Further notable results were:
1948: 1st, Italian men's championships of cross-country skiing, 50 km
1950: 2nd, Italian men's championships of cross-country skiing, 50 km
1951: 1st, Italian men's championships of cross-country skiing, 50 km