Anastasios Douvikas led the way with a hat-trick, scoring twice in the first half before completing his treble after the break. Nico Paz, Lucas Da Cunha, Marc-Oliver Kempf, Mattia Liberali, Martin Baturina and Matteo Papaccioli also found the net, while Ruben Aguilar scored Lens' only goal.
Douvikas opened the scoring after seven minutes and doubled Como's advantage in the 32nd, with Paz making it 3-0 before half-time. Da Cunha, Kempf, Douvikas and Liberali then extended the lead to seven, before Aguilar briefly reduced the deficit. Baturina added an eighth and 18-year-old Papaccioli completed the extraordinary result in stoppage time.
Lens coach Yannick Cahuzac made no attempt to disguise his disappointment.
"It's a heavy scoreline, we were completely dominated. We've got to have a long, hard look at ourselves and attempt to regain some pride against Marseille on Sunday."
Cahuzac had little explanation for the scale of the defeat, preferring to focus on how his players would respond.
"I can't offer you an in-depth analysis of what went wrong. We're hurting, but I'm going to concentrate on my side, and how we can pick them up from this."
He added: "We have to be able to look each other in the eyes, tell each other the truth. We have to pick ourselves up and turn our attention to Sunday. Unfortunately, these things happen across the course of a career."
Como coach Cesc Fàbregas, meanwhile, urged his players not to get carried away by a result that will be remembered by the club.
"It's been a happy evening. This is football; today everything went our way. Now we have to think about the next match, which is the ninth after the break. We have to finish as well as we can. It's a great evening for Como and our supporters."
The former Arsenal and Barcelona midfielder also stressed the importance of keeping their feet on the ground.
"Now, feet on the ground and humility. We have to keep working. We have to learn, not act like we're superstars. Today everything went our way and I have to thank everyone."
Fàbregas highlighted the importance of having his squad available, particularly with difficult fixtures against Paris Saint-Germain and Barcelona still to come.
"For us it is vital to have everyone available. There is a lot of football still to play, but this was a beautiful night for the club."
Como's nine goals rewrote the competition's record books and delivered a remarkable response to their earlier defeat by Feyenoord. For Lens, the scale of the loss leaves Cahuzac with an immediate task: restoring confidence before Sunday's meeting with Marseille.