“…Although a range of spontaneous tumors have been described in Xenopus over the years, from hepatomoa, teratoma, renal carcinoma, fibroma, fibrosarcoma, ovarian dysgerminoma, melanophoroma, lymphoma (reviewed in [1, 32]) to pancreatic carcinoma [33], deriving tumor cell lines, crucial for tumor immunity studies, has been met with limited success. A notable exception, however, is isolation and characterization of several transplantable lymphoid tumor lines that were derived from spontaneous thymic tumors [34].…”