Pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP) are uncommon inflammatory skin disorders that occasionally share clinicopathological features. Differentiating between the two entities remains problematic, and a definitive diagnosis usually requires multi-step investigations, which is an enormous challenge to physicians. We hereby report a rare case of a 22-year-old female patient diagnosed with PLEVA who later developed LyP type F, a new histological variant of LyP. Our report highlights that long-term follow-up is essential to determine associated hematologic malignancies, particularly in cases with recalcitrant or progressive cutaneous lesions of PLEVA and/or LyP.