HOTAIR and neoplasm: Since little is known about the role of lncRNAs in low incidence cancers, and there is a need to identify new molecular markers and therapeutic targets for these neoplasms, in this review we will discuss the role of lncRNAs, with the focus on HOTAIR, in head and neck rare cancers, soft tissue tumors, neuroendocrine tumors, rare digestive system tumors and central nervous system tumors.