Among primitive adenocarcinoma of nasal cavity and paranasal sinus, the 2005 WHO classification distinguishes two main categories: intestinal type adenocarcinoma (ITAC) and low-grade non-intestinal adenocarcinoma, entities with different clinical and epidemiological characteristics. Low-grade adenocarcinoma shows a respiratory type phenotype (CK20-/CK7+/CDX2-/villin-) and ITACs, an intestinal type profile (CK20+/CK7-/CDX2+/villin+). Because of histological, ultrastructural and phenotypical similarities between ITAC and colorectal adenocarcinomas, several studies have discussed a possible common pathway in carcinogenesis. But the review of literature shows conflicting results, suggesting different pathways of pathogenesis. Differential diagnoses of sinonasal intestinal-type adenocarcinoma are mainly respiratory epithelial adenomatoid hamartomas, inverted schneiderian papillomas, salivary glands-type carcinoma and more rarely metastasis of adenocarcinoma.