From The Horse's Mouth: Nissan Says Not To Overlook Inspecting The Radiator Cap On Overheating Nissans.
Some of the caps have been found to suffer from a case of swollen gasket. The rubber gasket that seals the cap is backed by a metal disc that is supposed to be slightly larger in diameter than the gasket when viewing the under-side of the removed cap. A rubber gasket that has swollen, extends beyond the metal disc so that the metal can no longer be seen. This can cause the cap to not vent properly and result in coolant loss and overheating, according to Nissan. Also, they recommend replacing any cap that has foreign material on the gasket or its retainer.
This is just one of many items that should be checked.
CSA