AdenocarcinomaUp one level
Compared to adenomas, adenocarcinomas show greater cytological atypia, increased frequency of mitoses, regional variation in growth pattern, more papillary structures, have size over 5 mm in diameter, show invasion of vessels, large airways or pleura, as well as lymphatic and hematogenous metastases.
- Papillary adenocarcinoma
- Papillae have fibrovascular core lined by cuboidal to columnar cells with varying degree of pleomorphism.
- Acinar adenocarcinoma
- Composed of predominately glandular structures, lined by cuboidal to tall cells, sometimes with mucous production. Cases with the presence of at least 10% of squamous or neuroendocrine component should be allocated to adenosquamous or neuroendocrine carcinoma, respectively.
- Solid adenocarcinoma
- Uniformly solid character of the lesions is usually indicative of a well differentiated tumor. No solid adenocarcinomas have observed in our series. However, rare cases have been described by others. In human pathology this diagnosis is usually based on detection of mucin after periodic acid-Schiff reaction with diastase (α-amylase) digestion.
- Adenocarcinoma with mixed subtypes
- Consists of various combinations of papillary, acinar and solid structures.
- Adenocarcinoma, NOS
- Tumors with glandular components but distinct from any other specific subtype of adenocarcinoma. This subgroup can be used for temporary allocation of novel lesions.