The Azzurri had the chance to narrow Juventus' lead to just two points with victory but Samp stood resolutely firm at the San Paolo, with visiting goalkeeper Sergio Romero proving difficult to break down behind an organised defence.
Cavani was not among those who came particularly close to breaking Samp's resolve and the Uruguayan faced a wall of whistles and catcalls from the stands after failing to find the back of the net for the fourth game in a row.
He told Gazzetta.it: "I still believe this could be the year of the Scudetto. The Italian championship is finely balanced and we can beat anybody.
"We will fight to realise our dream of winning the Scudetto.
"I promise you, I am giving my all in training and I'm always striving to be on top of my game. I've just had a bit of bad luck recently.
"It's just a difficult period for me and I'm working hard to get back among the goals."
Cavani has already scored 25 goals to boost Napoli's cause but the fans could not hide their frustration about his current barren streak.
"How much did that hurt? It didn't," he added. "They're just whistling because they're unhappy and we really wanted to win the game too.
"Now we will try to move forwards. It's normal to hear whistles when you don't win a game."
Napoli director of sport Riccardo Bigon remains similarly optimistic.
He said: "Everybody knows that we have been doing some extraordinary things.
"We find ourselves four points away from the leaders, who we are yet to play, and there are 13 games left this season.
"This team is in control of its own destiny and there's a lot of optimism around the place."
To add insult to injury, midfielder Marek Hamsik was then mugged at gunpoint on his way to Napoli airport, according to Radio Marte.
Sampdoria boss Delio Rossi was banned from the touchline so it fell to his assistant Fedele Limone to analyse the latest instalment of a four-game unbeaten run.
"We wanted to bring continuity to our results and it was key that we moved further clear of the relegation places," he said.
"We played a great game from a defensive point of view. We gave precious little away to Napoli, who are inferior only to Juventus and that shows in the league table."
Young striker Mauro Icardi was the subject of a failed 12million euro bid from Napoli in January, with Inter Milan also reported to be interested in signing the dynamic Argentinian.
Limone added: "For now he's our player but we'll see where we are in June. He's training well and there are three long months to go before June."