After 4,186 visual or "gross" exams, pathologists found no cases of disease.
And after 1,066 microscopic exams, pathologists found only 18 cases of malignant disease, all of which were previously suspected either because the patients had previously received organ transplants, and were thus at higher risk, or because a surgeon had noticed the tissue appeared suspicious.
Nevertheless, wrote Marc C. Thorne, MD, assistant professor of otolaryngology at the U-M Medical School, hospital pathologists still routinely perform these two types of exams on removed tonsils even though neither produces significant cases of disease unless performed in high-risk patients.
For gross or visual pathology exams, he wrote, "Exploration of the cost implications suggests that such a practice is not a cost-effective use of limited healthcare resources." The second test, which looks for diseased tissue with a microscope, "is appropriate for post-transplantation patients and in cases of surgeon suspicion," a minority of those undergoing tonsillectomy.
McHugh's study, authored with U-M colleagues, is published in this month's issue of the American Academy of Otolaryngology-Head and Neck Surgery.
In a sample of 4,186 tonsillectomies at the hospital between 1996 and 2008, he wrote, the cost of both tests was $250,000. The paper also looked at other research papers examining the same topic, and concluded that the cost of finding an unsuspected lymphoma in a child through microscopic evaluation is $766,500 per found case.
Tonsillectomies have long been one of the most commonly performed surgical procedures with about 250,000 operations performed in children a year in the U.S. Children are recommended for the procedure to curb sleep-disordered breathing or chronic infections of the tonsils.
But how frequently the operation is performed, and how often removed tonsil tissue is forwarded for more intense pathology exams is highly variable around the country, reflecting regional surgeon and otolaryngology practitioner preferences, according to the American Academy of Otolaryngology (AAO).
The microscopic tests were reimbursed by Medicare at $61.32 per patient in 2008, or double that if both tonsils underwent microscopic examination. The cost of a visual exam was $22.85.
In a statement, Thorne notes that he is not suggesting that it's not important to discover cancer and other diseases. "The question is what we might be giving up elsewhere in order to find those rare cases?"
He added, "If we're going to make a rational decision – say, 'I don't care how much it costs, missing a lymphoma in a child is unacceptable' – then we should be doing microscopy all the time. If we're just doing gross (visual) analysis, we're still spending a lot of money, yet we know we're unlikely to find anything that way."
In the paper's conclusion, the authors wrote, "This current economic analysis would tend to support a decision to either forego pathologic analysis of routine tonsillectomy specimens in children or to perform microscopic analysis routinely."