Similar to other adenocarcinoma, if this tumor is well differentiated (low grade) it will resemble the normal glandular structure. Poorly differentiated adenocarcinoma will not resemble the normal glands (high grade) and will be detected by seeing that they stain positive for mucin (which the glands produce). Adenocarcinoma can also be distinguished by staining for TTF-1, a cell marker for adenocarcinoma.As discussed previously, the category of adenocarcinoma includes are range of subtypes, and any one tumor tends to be heterogeneous in composition. Several major subtypes are currently recognized by the World Health Organization (WHO) and the International Association for the Study of Lung Cancer (IASLC) / American Thoracic Society (ATS) / European Respiratory Society (ERS): lepidic predominant adenocarcinoma, acinar predominant adenocarcinoma, papillary predominant adenocarcinoma, micropapillary predominant adenocarcinoma, solid predominant adenocarcinoma, and solid predominant with mucin production. In as many as 80% of these tumors, components of more than one subtype will be recognized. Surgically resected tumors should be classified by comprehensive histological subtyping, describing patterns of involvement in increments of 5%. The predominant histologic subtype is then used to classify the tumor overall. The predominant subtype is prognostic for survival after complete resection.To reveal the adenocarcinomatous lineage of the solid variant, demonstration of intracellular mucin production may be performed. Foci of squamous metaplasia and dysplasia may be present in the epithelium proximal to adenocarcinomas, but these are not the precursor lesions for this tumor. Rather, the precursor of peripheral adenocarcinomas has been termed atypical adenomatous hyperplasia (AAH).
Chronic progressive external ophthalmoplegia (CPEO) is a type of eye disorder characterized by slowly progressive inability to move the eyes and eyebrows. It is often the only feature of mitochondrial disease, in which case the term CPEO may be given as the diagnosis. In other people suffering from mitochondrial disease, CPEO occurs as part of a syndrome involving more than one part of the body, such as Kearns–Sayre syndrome. Occasionally CPEO may be caused by conditions other than mitochondrial diseases. Signs and symptoms
CPEO is a rare disease that may affect those of all ages, but typically manifests in the young adult years. CPEO is the most common manifestation of mitochondrial myopathy, occurring in an estimated two-thirds of all cases of mitochondrial myopathy. Patients typically present with ptosis (drooping eyelids). Other diseases like Graves disease, myasthenia gravis and glioma that may cause an external ophthalmoplegia must be ruled out. CPEO itself
CPEO is a slowly progressing disease. It may begin at any age and progresses over a period of 5–15 years. The first presenting symptom of ptosis is often unnoticed by the patient until the lids droop to the point of producing a visual field defect. Often, patients will tilt the head backwards to adjust for the slowly progressing ptosis of the lids. In addition, as the ptosis becomes complete, the patients will use the frontalis (forehead) muscle to help elevate the lids.