The mayor of Rome, which once hosted 5 million pilgrims, predicts a successful weekend

Hey Philadelphia, the mayor of Rome - a former Philadelphian himself - has a message for you: Don't sweat the security this weekend around Pope Francis' historic visit.

Ignazio R. Marino, an accomplished liver transplant surgeon, told a large audience at Temple University on Thursday night that his city last year hosted an event that drew five million - the canonization of two previous popes, John XXIII and John Paul II - and came through it just fine.

That's more than twice the size of the crowd expected here this weekend for Francis' visit.

"Everything went very well, and I'm pretty sure that everything will go as well here in Philadelphia in a couple days," said Marino, who worked at Thomas Jefferson University in Philadelphia from 2002 to 2006 before returning to Rome to start his political career. The audience laughed, prompting the mayor to quip: "Why do you laugh?"

"It will be a terrific day for this city," Marino assured those attending his lecture on his careers as a surgeon and as a politician at the university's Performing Arts Center. "And I'm pretty sure Mayor Nutter will perform very well."

Marino, who has been mayor since 2013, met with and advised Nutter on papal security in June when the mayor traveled to Rome. He said he gave Nutter a manual of procedures and protocols that his city had developed to handle security at the canonization.

Marino oversees the city that is home to the Vatican, and has become quite familiar with keeping safe a pope who likes to mingle with and touch the crowds.

"I can't tell you how tough it was to organize everything," Marino said after his talk.

More than 120 official delegations from countries around the world, including kings and queens, attended the canonization on April 27, in St. Peter's Square. Thousands slept in the streets, hoping to get as close as possible to Francis.

"We had to close a number of streets," he said. "You need to have at least one important route completely free of everything. If you have any kind of accident or somebody who has a heart attack or a terrorist attack, you need to have an escape route for security and health care."

The city also had to be prepared to distribute thousands of small bottles of water, he said.

One of the toughest challenges of the event, he added, came afterward: the cleanup.

"After the pope finished, we collected 100 tons of garbage," he said.

There also were some funny moments, like when security stopped a man carrying a backpack with bishop's clothing about 2 a.m. Turns out the man wasn't a threat.

"He wanted to put the clothes on so he could be allowed to enter in the more restricted area," Marino explained, to get closer to the dignitaries.

Marino, who is participating in the World Meeting of Families this week, had a lot of preparation for a challenging political career.

Born in Genoa, Marino attended Catholic University of the Sacred Heart School of Medicine and worked at a hospital in Rome for nine years, studying liver transplantation with such pioneers as Thomas E. Starzl, who performed the world's first human liver transplant. Over his 26 years as a surgeon, he has performed nearly 600 organ transplants.

He worked in Pittsburgh for 11 years before coming to Philadelphia to serve as a professor of surgery at Jefferson. He eventually became director of the university's division of transplantation.

"What I really love the most is the relationship with a patient," Marino said. "I really do believe that's the most important thing when you're a physician."

And when you're a politician, he said, it's the relationship with citizens.

ssnyder@phillynews.com

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