Dear Doctor: I've recently been diagnosed with meningioma, but my doctor tells me not to worry about it. That can't be right. What should I know?

Dear Reader: Meningiomas are the most common brain tumors within the central nervous system, and most are considered benign. As the name implies, meningiomas arise from the meninges, the layer of membranes that surrounds the brain and the spinal cord. Approximately 26,000 new cases are diagnosed each year, often found incidentally -- meaning they're detected via brain imaging for symptoms not related to the tumor. The likelihood of an incidental meningioma increases as a person gets older. In fact, a 2016 study of MRIs performed in 5,800 healthy adults with an average age of 65 found that 2.5 percent had meningiomas.

Ionizing radiation, a history of breast cancer, obesity and a family history of meningiomas are all risk factors for this type of tumor.

Of meningiomas, 80 to 90 percent are classified as grade 1, meaning they're slow-growing because the cells within them don't replicate rapidly. This is most likely the type of meningioma that you have. An additional 10 to 15 percent of meningiomas are classified as grade 2, meaning the cells within them replicate more rapidly and are more likely to invade local structures, making them more dangerous. A final 1 to 3 percent of meningiomas are considered grade 3, because the cells within them replicate very rapidly. These types of cancerous meningiomas are more difficult to treat and can spread to distant sites.

A CT scan or an MRI of the brain should be able to detect signs that indicate whether a meningioma is atypical or malignant, such as by assessing whether the tumor has swelling around it or whether it's invading the bone.

If your doctor says you have no reason to be concerned, that's probably because the meningioma is in an area where it isn't compressing any portion of the brain. Some meningiomas, even though they are grade 1, are located in an area of the brain where they compress nerves. This can lead to alterations in vision, loss of hearing or smell, even weakness of the arms and legs and, rarely, if the tumor blocks the movement of fluid within the brain, confusion. Lastly, meningiomas increase the risk of having seizures; this risk appears to be more common in men.

That said, meningiomas occur more often in women than in men. One interesting aspect of meningiomas is that they have receptors for progesterone and estrogen. Theoretically, taking hormone replacement after menopause could incite tumor growth. Although research has not supported this specific connection, some studies have shown a slightly increased rate of meningiomas among women who did hormone replacement. So, if you are undergoing such therapy, I would recommend stopping it.

If indeed your tumor is grade 1 and not compressing any vital structures of the brain, I -- like your physician -- would caution against any surgical or radiation treatment for the tumor. Obviously, such treatments have side effects, and the benefit wouldn't be worth the risk. That said, you should follow up with regular MRIs -- first on a yearly basis. If there's no change in the size of the tumor after three to five years, then you can lengthen the interval in between MRIs.

In the meantime, stay calm and know that, as your doctor said, there's likely no cause for alarm.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: My husband and two sons all have athlete's foot, and my daughter and I don't want to catch it. Now that it's in the house, can we get rid of it?

Dear Reader: Athlete's foot, also known as tinea pedis, is a common fungal infection. Anyone who has suffered through the maddening itch of athlete's foot, often in the delicate skin between the toes, is primed to be vigilant about preventing future infections.

Symptoms include that relentless itch, which can occur anywhere on the foot that the fungus is active, redness, and cracked, flaking or scaly skin. In some cases, tiny blisters may be present. Treatment with over-the-counter antifungal medications is usually successful. But be sure to follow the entire prescribed course of treatment. Even when it looks as though the infection has cleared up, the fungus can still be present, and therefore reinfection is possible.

A variety of different fungi can cause athlete's foot, but they all have one thing in common -- they thrive on moisture. That's the key to understanding how and where one contracts athlete's foot. It's also the answer to how to combat it.

Athlete's foot spreads either through contact with fungi or by contact with infected skin. Perpetually damp areas like locker rooms, bathroom floors, showers and swimming pools are prime breeding grounds for the fungi. They can also live in socks, shoes and towels, all of which tend to remain moist. Someone with athlete's foot should never share shoes or socks, as the infection can spread easily.

With the men in your family now assiduously applying anti-fungal products and keeping their footwear to themselves, let's talk about strategies to stop the spread of the infection.

-- Wash all socks, towels, bath mats, sheets and any other items that may have come into contact with the infection in the hottest water possible. If the fabrics can tolerate it, a cap of Lysol disinfectant in the wash is helpful. Dry thoroughly, and at the highest heat setting possible. Keep separate from regular laundry.

-- Always wear sandals when walking in moist areas, such as the bathroom, public showers, pools and locker rooms. (And since the fungus can remain alive for a time even in dry areas, it's best to never walk barefoot in hotel rooms.)

-- Keep feet clean and dry. Wash carefully and dry thoroughly, especially between toes. Use talcum powder or an antifungal powder as extra insurance. Make sure that toenails, which can house the fungus, are clipped short and kept clean. Change socks daily.

-- While the athlete's foot infection is active, put socks on first, and then underwear. The same fungi that cause athlete's foot are responsible for jock itch.

-- Air out shoes between wearings. Sunlight is good. Fumigating with a blast of Lysol is better. (Be sure to let the shoes dry completely before their next use.)

Finally, if nonprescription antifungals don't work, if the infection keeps coming back and for anyone who has diabetes, it is important to see your doctor.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I have a Zenker's diverticulum that, after 10 years, seems to be very large, judging by the volume it holds. At virtually every meal, I choke on food clogged in my esophagus, then I aspirate, then I cough for 10 minutes. Are my aspiration-related pneumonia risks high enough to warrant surgery?

Dear Reader: Think of the esophagus as a long tube connecting your mouth to your stomach. A Zenker's diverticulum occurs when a pouch forms in the back of the esophagus because of a weakness of the constricting muscles. Zenker's diverticula occur five times more often in males than females, with most patients developing the condition after the age of 60. The pouch that forms can be small, but can also be very large. Your symptoms fit the latter description.

With a minor Zenker's diverticulum, a person may develop bad breath or a gurgling in the throat. When the pouch is large, more severe symptoms can occur, such as a mass in the neck, regurgitation of food into the mouth and, lastly, potential aspiration of food into the lungs, which can lead to pneumonia. Your symptoms fit the description of a large diverticulum, so you're right to be concerned.

Because your symptoms are so severe, and because pneumonia is dangerous, you should consider surgery. Traditionally, the removal of a diverticulum was done via an incision in the neck and then removal of the muscle layers that separate the diverticulum from the esophagus. This type of surgery resolves symptoms in 90 to 95 percent of patients. But note that complications include vocal cord paralysis, infection and perforation of the esophagus; such complications occur 11 percent of the time, with 3 percent of patients having nerve damage that leads to vocal difficulties.

Another option is to do the procedure by endoscopy, which doesn't require cutting into the neck. Instead, the surgeon goes through the mouth with a tube called an endoscope, either a rigid one or a flexible one. This device allows the surgeon to look into the esophagus directly and then cut away the muscle -- using a scalpel or a laser -- separating the esophagus from the diverticulum.

The success rate of a procedure using a rigid endoscope, which has been in use since the 1960s, is 90 percent, with a complication rate of 8 percent. The biggest potential risk is of infection of the middle portion of the chest, which occurs in 2 percent of patients. Like traditional surgery, this procedure requires general anesthesia. Also, note that the diverticulum reforms in 10 percent of patients.

Use of a flexible endoscope, which has been available for about 20 years, does not require general anesthesia, but often requires more than one treatment. The success rate is also about 90 percent, but the average rate of complications is lower, about 6 percent.

Endoscopic removal is more difficult in people with shorter necks. Also, younger patients -- those between the ages of 50 and 60 -- who have large diverticulum would benefit from an open surgical approach.

In summary, if the Zenker's diverticulum is causing aspiration, I would recommend surgical treatment. Because the condition is very rare, you should find a doctor who is experienced in either the open or endoscopic approaches.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)