Cockles, and Mussels

Looking further at that  article about a transmissible cancer in clams, it appears that cell line infections are common in bivalves – oysters, cockles, mussels – without being recognized as such until now.  Could be true in other filter-feeders – sponges, brachiopods, etc. Gills might also be a transmission mechanism- so cell line infections may be a general problem for oceanic organisms.