TSC2 and kidney neoplasm: The potential utility of rapamycin treatment for a prolonged duration was suggested by the results of a previous preclinical study using C57BL/6 Tsc2+/- mice in which we noted that a rapamycin dosing schedule that included daily treatment for 2 months and weekly treatment for 6 months, resulted in a dramatic 94.5% reduction in kidney tumor severity [61].