5 Diagnoses That Call for a Second Opinion

A medical diagnosis isn't always black and white. Indeed, it's often clouded by shades of gray. Some diseases begin with symptoms so subtle or common that they confound even experienced doctors. Other times, a patient knows exactly what's wrong but can't decide which treatment is best.

Enter the second opinion. It's never a bad idea to seek a second opinion, but if you receive one of these five diagnoses, it's practically a must.

1. Unusual or Hard-to-Diagnose Cancers

If you've been diagnosed with an uncommon cancer -- or if there's any question about whether it's truly cancer -- seek a second opinion from a pathologist who has expertise in diagnosing this type of malignancy. After all, the diagnosis will determine which treatment is best.  

"There are certain kinds of tumors that provide a lot more difficulties in diagnosis," says John E. Tomaszewski, MD, FASCP, vice chairman of Anatomic Pathology-Hospital Services at the University of Pennsylvania School of Medicine. For example, sarcomas -- an uncommon cancer of soft tissues, such as muscle or fat -- can be complex to classify. "A general pathologist may not see a lot of soft-tissue tumors," he says.

Major medical centers that see larger numbers of rare or unusual tumors are often a better choice for a second opinion than a smaller hospital, according to John S.J. Brooks, MD, FASCP, president of the American Society for Clinical Pathology. "These folks that have very rare tumors, [a hospital] near them may only see very few," he says. 

Getting that second opinion can help catch errors.

"Anytime there's uncertainty, it's always fine [to get a second opinion]," Tomaszewski says. "Pathology ... is like every other area of medicine. There are things that are very clear and things that are on the borderline."

2. ADHD in Children Under Age 6

With no specific lab test for attention deficit hyperactivity disorder (ADHD), the problem can be tough to diagnose accurately. A doctor's judgment comes into play; he or she may diagnose ADHD if a child shows hyperactivity, inattention, and impulsivity in at least two settings, such as home and school.

When a child under age 6 is diagnosed with ADHD, parents may want a second opinion from a specialist, such as a child psychiatrist, says Sara Rizvi, MD, assistant professor of pediatrics at the Baylor College of Medicine. That's because ADHD symptoms, such as too much talking or fidgeting, can overlap with behavior that's typical among young children.

"Many of the symptoms are common among preschool children," Rizvi says. "Part of it is because of their developmental stage and level of activity and normal short attention spans." A second opinion can help determine if symptoms are serious enough to be classified as ADHD.

It's also crucial to rule out other mental disorders that can be confused with ADHD, according to Rizvi. These include developmental problems, learning disabilities, anxiety, and depression. Sometimes, children who witness domestic violence may behave in ways that suggest ADHD, Rizvi says. "They tend to be more inattentive to their class work, more impulsive. A lot of those children are actually misdiagnosed with ADHD when in fact they may be manifesting symptoms of posttraumatic stress disorder."