Napoli and Atalanta still have a chance to continue their good trend in this match, even though their opponents are top teams but I am sure Napoli and Atalanta will not lose. Even though for example they can't win, but at least they can still end the match with a draw at least that's better than not getting any points at all. So yes, I still believe that even though Napoli are playing away, they are still on fire which is certainly not easy for Roma to beat Napoli.
Napoli and Atalanta in recent seasons have been playing like Roma in the past. They are attacking aggressively and their power is more skewed in attacking. It is reflected on their goal difference and total goals they have scored so far.
Despite of impressive attacking, their defense systems are finishing their tasks well enough to secure winning matches for them. However, they have yet been tested seriously enough about their defense ability that they must have it good to maintain the first and second positions. If their defense performs worse, they will end this season with lot of regret even they have some amazing periods.
Regarding Lazio, I think even though they are in 5th place at the moment, they are still not consistent enough. Because Lazio also have to focus on the Europa League which is still not safe, for sure it will be a good opportunity for Atalanta because Atalanta will also play at home and Atalanta will only focus on Serie A this season.
Lazio and Roma are creating an interesting internal competition. They are standing at the fourth and fifth positions and it is long time since a last season we see two clubs from Rome have such high rankings on the table and compete directly with each other for the fourth position.
Both Roma and Lazio have to work hard because other clubs like Inter Milan, Juventus and Udinese won't let them get the fourth position easily. That one means a ticket to play in Champions League that in turn brings more income for the club.