After about four months of eating through a feeding tube to treat his head and neck cancer, Dick Dusenbery looked forward to sinking into a slice of pizza.

A cracker and water was his first meal, as doctors wanted to see he could swallow after radiation.

“It’s still a little tough eating,” said Dusenbery, 56, who was diagnosed with oropharyngeal squamous cell carcinoma in April 2011. The cancer developed as a tumor in his tonsil, a tumor in his lymph nodes and a small tumor on the back of his tongue.

The cause? Human papillomavirus, the most common sexually transmitted virus.

Smoking and drinking had been considered the main causes of oropharyngeal cancer. But over the last three decades the number of HPV-caused oropharyngeal cancer patients has dramatically increased, from 20 percent of such cancers in 1998 to a whopping 70 percent in 2004, according to a study published in 2011 in the Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology.

HPV-positive oropharyngeal cancer is transmitted through oral sex. The virus could be embedded in the tissues of the tonsils and the base of the tongue for years before it turns into cancer, said Dr. Andre Abitbol, associate medical director of the Department of Radiation Oncology at Baptist Hospital.

Problems swallowing, sore throat and pain are some of the likely symptoms, said Dr. Lisa Reale, medical oncologist at Baptist Health South Florida. There could also be ear pain, mouth bleeding, difficulty moving the tongue and a visible neck mass, added Dr. Michael Medina, an ear, throat and nose doctor with a specialty in head and neck cancer surgery at Cleveland Clinic Florida in Weston.

“This isn’t a pretty picture of cancer treatment,” Abitbol said. “This is a rough, rough treatment.”

Part of Dusenbery’s treatment involved radiation, which left him with a swollen throat and tongue for months.

“I didn’t want to talk. I didn’t want to swallow,” he said. “Just think if you had to swallow cut glass.”

Dusenbery nourished himself with a feeding tube. Every day an ivory-colored nutrient pack would trickle down the tube so he could get 2,200 calories.

“It’s very depressing knowing that you are going to have to get it put in,” he said. “But once it is in, you didn’t have to worry about what you are going to eat or when you are going to eat it.”

The good news is that this type of cancer is more treatable than tobacco or alcohol-caused oropharyngeal cancer.

In the past, doctors would cut the jaw in three places to get to the cancer. Now they remove the tumor through the mouth using robotic or laser surgery, a more precise and less-invasive method.

“You don’t have to go through too much normal tissue to reach the cancer, so that is why you have normal function post surgery,” said Medina of Cleveland Clinic.

Dusenbery’s battle with cancer started when he was undergoing a surgery to get his tonsils out. The surgeon saw the tumor in the extracted tonsil.

Dusenbery then started chemotherapy – one round every three weeks, five cycles. Radiation coupled with milder chemotherapy medications followed.

That was in November and December.

On a recent visit to Dusenbery’s South Miami-Dade home, he and his wife, Sharon, 55, were getting ready for a day of boating. He unbuttoned his tropical shirt to show the fading scar under his chest where the feeding tube had been inserted, just inches from where a gold anchor dangled from his neck. “The pain was one of the hard parts. I couldn’t do what I wanted to do,” he said. “Now I have started to enjoy the things I used to enjoy before.”