The former New York City police detective who was a leader in the fight for the Sept. 11 Victim Compensation Fund was posthumously honored with a key to his city.
"To the entire family, you shared Lou with this city," de Blasio said, according to BC 4 New York. "You shared him in a way we will never forget. He made this a better place. It's just a true statement that one person can do so much."
De Blasio added: “We can honor him in a way that few people have been honored in the history of this city because he belongs in that pantheon."
He appeared with former “Daily Show” host Jon Stewart this summer to plead with Congress to extend the compensation fund.
Alvarez spent three months laboring in the World Trade Center rubble after the 2001 attacks.
Alvarez had discovered he was going into liver failure after finishing his 69th round of chemotherapy, and gave his last-ever interview on "Shepard Smith Reporting."
Alvarez told Smith he had no regrets, and was simply doing his job on the day of the attacks.
"I have no regrets -- no regrets whatsoever," he said. "9/11 happened. We got called down. It's my job as an NYPD detective to respond to emergencies. So, no hesitation. We went down, spent about three months down there doing the bucket brigade, doing rooftop detail, trying to find remains. I did what every other FDNY, NYPD, EMS worker -- everybody. I'm nobody special. I did what all the other guys did. And now we're paying the price for it."