When 17-year-old Jacob Barnes walked into his neurosurgeon’s office in January 2012, he didn’t look like a typical boy his age. In fact, at 5 feet 2 inches tall and around 145 pounds, and with a smooth face he’d never needed to shave, Barnes looked more like he was 11.

Growing up, his relatively younger, scrawnier appearance had never bothered him much. But when Jacob was diagnosed with a rare congenital condition marked by a brain tumor on his pituitary gland mere months before, he and his family’s concern surpassed that of a superficial basis.

Today, Jacob stands at 6 feet 1 inch tall, weighs about 241 pounds and can grow facial hair. After undergoing a minimally invasive procedure and regularly taking growth hormones, Jacob is healthy and developmentally back on track.

“Now, I just kind of feel normal,” 21-year-old Jacob, a junior at the University of Findlay, in Findlay, Ohio, told FoxNews.com.

Searching for answers

Barnes was diagnosed with craniopharyngioma in November 2011 after suffering from severe migraines since he was a young boy. The condition is diagnosed most commonly in children and affects function of the pituitary gland, which controls water balance, but also all the glands in the body like thyroid hormones, the adrenal glands, and sperm and prolactin production. Pea-sized, the pituitary gland is located at the bottom of the brain and the hypothalamus.

While vision loss is the most common early symptom of craniopharymgioma among older people, physical developmental delays, extreme thirst and frequent urination usually exhibit first in younger people with the condition.

“All [Jacob’s] hormones were really below average,” Dr. Daniel Prevedello, an associate professor in the department of neurological surgery at The Ohio State University Wexner Medical Center, told FoxNews.com, “so his gland was not working at all.”

Prevedello, who heads the center’s Minimally Invasive Cranial Surgery Program and operated on Jacob, said he sees about five cases of craniopharyngioma a year. Usually, those cases are among children ages 6 to 12.

“At that point, you figure out they’re not developing,” Prevedello said. “Most boys will develop at age of 12, 13, they start having the hair and their voice changes, so when you see someone at 13, 14 and not developing yet, and at 15 or 16, that’s rare.”

Jacob’s mom, Deborah Barnes, who lives in Norwalk, Ohio, said migraines throughout youth were the only sign something may have been off with Jacob. Sometime during grade school, a neurologist gave him a prescription for them, but she couldn’t recall the name of the medication. Jacob was otherwise healthy.

“I wasn’t really concerned until his freshman year of high school,” Deborah, 59, told FoxNews.com. “He was always shorter than most of the girls, and in class pictures he was always in the front row.” Deborah added that Jacob’s physical developments never impeded on his social life, and that he always had friends. Jacob agreed.

“I was never one to be self-conscious about how I looked,” Jacob said.

But in his junior year of high school, Jacob began having unbearable neck pains. One day after school, Deborah recalled him sitting on the recliner and crying because the pain was so intense.

“I said, ‘That’s enough, I’m calling someone,’” Deborah remembered.

At the time, the Barnes family had begun seeing a new physician, who immediately suspected something was wrong based on Jacob’s appearance relative to his age, and referred them to an endocrinologist. There, he got an MRI that revealed the 3.4-centimeter-wide brain tumor.

“Cancer of course is the first thing you think, and [the endocrinologist] said it’s probably not cancer,’” Deborah recalled from the phone call one night over dinner. “I was pretty upset, and I’m sure he was scared.”

Operating by camera

They traveled to Columbus to seek treatment at the Cleveland Clinic, where they could have undergone a craniotomy to extract the tumor, which posed a greater risk of compromising his eyesight from contact with the optic nerves, as those nerves are located directly below the pituitary gland. Performing a craniotomy involves surgically opening the skull and exposing the brain.

Doctors at the Cleveland Clinic referred Jacob to the Ohio Wexner Medical Center, where Prevedello and his team specialize in a minimally invasive procedure called the endoscopic endonasal approach, whereby they make a small incision and extract brain tumor through the nose. Prevedello is one of only a few neurosurgeons worldwide who uses this approach.

He and an ear, nose and throat (ENT) doctor performed the 10-hour surgery on Jacob on Feb. 10, 2012. They used a camera, and several tools that can pass through the nostrils, including scissors, a suction kit, dissectors, a drill and an endoscope, which is akin to a small pen that acts like a microscope and a flashlight. The ENT drives the camera, and Prevedello watches the footage above the patient on a screen at the top of the room as he uses his two hands to dissect the tumor.

Prevedello said Jacob’s surgery was uneventful, and he and the ENT were able to remove the entire tumor. Jacob’s eyesight, which also had begun to suffer from his diagnosis, was also restored.

Jacob was in the hospital for four days and returned to school two weeks after he was discharged. He didn’t take painkillers after surgery.

Prevedello said the fact Jacob responded well to the growth hormones was lucky and unique because sometimes, if the diagnosis is caught too late, individuals won’t because their bones have already fully developed.

Staying positive about Jacob’s future

For now, Jacob attends follow-up appointments with Prevedello once each December, when he gets an MRI and an X-ray of his hand to see how his growth platelets are progressing.

Because his pituitary gland is dead, he must also take about six medications to perform the functions the gland otherwise would. Those include a steroid for energy and immune support, levothyroxine to assist with thyroid production, desmopressin for diabetes insipidus, and nutropin, an injectable growth hormone.

“My roommates say, ‘I could never do that!’” Jacob said of the injections, which he self-administers every other day. “I say, ‘You get used to it if you don’t have any options.’ Now, it’s just second nature.”

Deborah said Jacob is now “mouthier” and “happier” since undergoing the surgery and taking growth hormones.

“He’s not disrespectful, but he speaks up more,” she said. “He didn’t before; he was kind of just a quiet kid.”

There’s a 30 percent chance the tumor will return even with a successful surgery, Prevedello said. It commonly recurs among young people who take growth hormones.

“These tumors have receptors to growth hormones, so if you take the hormones you increase the risk of it coming back,” Prevedello explained.

But the Barnes family isn’t worried about that just yet.

Deborah said despite Jacob’s diagnosis, she considers their family lucky.

“We feel blessed,” she said. “I’ve lost two nephews who died at age 31 to diabetes and a nice who died of cancer at 19 … if this is the worst thing we go through, I feel blessed.”

Jacob said he tries not to let the potential for recurrence weigh on his mind. Plus, he’s too busy being a typical junior college student—passing his free time with his two roommates and playing video games in an on-campus club. He’s also studying hard— he’s slated to get his bachelor’s degree in computer science in spring 2017.

“I always like to be optimistic, and I hope it (tumor recurrence) never happens,” Jacob said, "but if it does, I’ll get it taken care of as easy as last time.”