Structure of finite groups with restrictions on the set of conjugacy classes sizes

Let $N(G)$ be the set of conjugacy classes sizes of $G$. We prove that if $N(G)=\mathrm{\Omega }\times \{1,n\}$ for specific set $\mathrm{\Omega }$ of integers, then $G\simeq A\times B$ where $N(A)=\mathrm{\Omega }$, $N(B)=\{1,n\}$, and $n$ is a power of prime.