She thought she had insurance coverage. Then a tumor was flagged as a pre-existing condition.

This is part of The Cost of Denial, NBC News’ reporting on insurance in America. If you are dealing with seemingly inappropriate bills or a denial of coverage, care or repairs for health, home or auto, email us at Costofdenial@nbcuni.com. Lisa Brundridge was recovering well from her surgery to remove a tumor from her spine when she got a notice from her health insurance provider that made her feel sick to her stomach: Her plan had refused to cover the nearly half-million-dollar combined cost of the operation and medical tests leading up to it.