Jarrett Allen scored 27 points and grabbed 14 rebounds, Donovan Mitchell added 26 points and Evan Mobley chipped in 20 for the Cavaliers, who notched their eighth straight win to push their league-best record to 29-4.
James, whose four NBA titles include a 2016 championship with his hometown team Cleveland, scored 23 points with four rebounds, seven assists and a blocked shot.
It was his first game since his 40th birthday on Monday, and made James the first player in league history to play a game in his teens and in his 40s.
Austin Reaves led the Lakers with an impressive near-triple-double of 35 points, nine rebounds and 10 assists.
Anthony Davis scored 28 points and grabbed 13 rebounds, but after twice edging ahead in the second quarter the Lakers trailed by five at halftime and never led in the second half.
There was less drama in Boston, where the Celtics won by the second-largest margin of victory in franchise history -- trailing only their 56-point triumph at Chicago in December 2018.
Jayson Tatum scored 18 of his 23 points in the third quarter, when the Celtics out-scored the Raptors 45-18 to effectively put the game out of reach.
Payton Pritchard scored 19 points off the bench as seven Celtics players scored in double figures.
The Celtics connected on 22 of their 43 three-point attempts as they handed the Raptors an 11th straight defeat.
Celtics coach Joe Mazzulla said the big win -- after the Celtics dropped four of their last six games -- was just part of the process as the Celtics try to repeat as champions.
"There's still stuff that we've got to work on... we've just got to continue to be better," Mazzulla said.
Bucks rally
The Milwaukee Bucks erased a 19-point deficit on the way to a 120-112 victory over the Indiana Pacers.
Bucks star Giannis Antetokounmpo, back after missing three games because of illness, found his rhythm after scoring just four points in the first half, finishing with 30 points and 12 rebounds.
Brook Lopez added 16 points and reserves Bobby Portis Jr. and Gary Trent Jr. scored 14 points each for Milwaukee, who trailed 83-64 midway through the third quarter.
"These are the type of games you need throughout a season to keep you going," Portis said. "It was a great game for us, especially going forward, that we can look back on like: OK, cool, we do it one time we can do it again and just keep building, keep building."
Another big night from Victor Wembanyama saw the San Antonio Spurs finish the year with a lopsided 122-86 victory over the Los Angeles Clippers.
Wembanyama closed out a December to remember with 27 points, nine rebounds, five assists, one steal and three blocked shots in less than 26 minutes on the court.
His 17 points in the first quarter matched the Clippers' total in the period.
In Oklahoma City, Shai Gilgeous-Alexander scored 40 points and the Thunder notched their 12th straight regular-season victory, 113-105 over the Minnesota Timberwolves.
The Thunder trailed by as many as 12 in the second quarter and were down 52-46 at half time.
But they out-scored the Timberwolves 43-23 in the third quarter and never trailed in the fourth on the way to a seventh consecutive win since they fell to Milwaukee in the NBA Cup final, which doesn't count as part of the regular season.
