It wasn’t quite “We Are the World,” but an eclectic, impromptu choir of more than 30 voices gathered in a Treme recording studio Monday to sing the praises of the Tulane Cancer Center. The talent spectrum ranged from Grammy winner Irma Thomas, Vince Vance, Al “Carnival Time” Johnson, Charmaine Neville and Benny Grunch to three “popes” in the “Bless You Boys” costumes they wear to Saints games.

At Esplanade Studios, a former church near the intersection of Esplanade Avenue and North Broad Street, they joined forces on “You’re Not Alone!,” a new song written for the occasion by Michael O’Hara.

In the early 1980s, O’Hara, clad in his trademark headscarf, was the decadent lead singer of local rock and soul band The Sheiks. They staged many a sweaty, raucous show at Jimmy’s Music Club.

O’Hara left the band in 1985 and moved to Los Angeles. He got clean and sober, wrote songs for Anita Baker, Jody Watley and Patti Labelle, and earned four Grammy nominations. He eventually became a preacher based in Texas.

In 2014, Jimmy Anselmo, the owner of Jimmy’s, convinced O’Hara to return to New Orleans for the first time in 30 years and perform Sheiks songs. Now O’Hara has moved back to New Orleans full-time, and has founded a new band called Resurrection.

Anselmo recruited O’Hara for the Tulane project after a chance meeting at a Metairie sushi restaurant with Gay Sperling, whose Brandateria marketing firm works with the cancer center. For both O’Hara and Anselmo, the cause is personal. Anselmo was diagnosed with prostate cancer eight years ago; it is now in remission. O’Hara lost his father to cancer.

The chorus of “You’re Not Alone” states, “So when you need a helping hand, and people who understand/At Tulane Cancer Center, you’re not alone.” The plan is to use the audio recording, as well as video from Monday’s recording session, for radio and TV ads. A fundraising CD and DVD are also possibilities.

“It’s about raising awareness, and raising hope,” said Melanie Cross, the Tulane Cancer Center’s communications manager.

Anselmo, O’Hara and local talent agent Judy Aucoin used their considerable powers of persuasion to convince an array of singers to volunteer their services. Three dozen turned up at Esplanade Studios on Monday.

Each took his or her place on a tiered riser erected in front of the former church’s towering pipe organ. In the top right corner, Johnson stood next to Vance, the Topcats’ Rob Schulte and the three “popes.”

O’Hara wore a flowing black and gold robe and matching headscarf a la his Sheik persona. Members of Resurrection pantomimed with their instruments for the cameras; their parts were recorded separately.

The singers swayed in time until someone noticed that the microphones were picking up squeaks. “Okay, we’ll just stand still,” O’Hara said.

He pointed out singer and harmonica player J.D. Hill. “We are so blessed to have J.D. with us. J.D. has been battling cancer but he’s here and he’s doing well.”

O’Hara conducted the impromptu choir with a firm hand. “Gentleman, I’m going to have to ask you to stop talking, or I’m going to have to separate you,” he scolded at one point.

As the afternoon wore on, he strove to maintain the group’s focus through multiple takes. “We’re going to keep doing it over and over until you understand it and it’s right.”

He listened closely. “We need to do that again, because some people weren’t singing that first note.”

Irma Thomas, for one, took O’Hara’s strict direction in stride. “He’s just another choir director,” said Thomas, who sings in church on weekends. “I’m used to it.”

The choir finally nailed the “big gospel finish” O’Hara sought. The session ended with a round of applause.

“It was fun,” said Lena Prima, daughter of the late Louis Prima. “I’ve never been part of something like this. It makes me feel like I’m part of the community.”