Master Adenocarcinoma of the Lung with Picmonic for Medicine

Adenocarcinoma cases account for half of lung cancer cases, making it the most common lung cancer overall (except for metastases).

Adenocarcinoma is the most common lung cancer in nonsmokers. It has a lower association with smoking among other major lung cancers like small cell and squamous cell carcinoma. Rather, adenocarcinoma may be related to pulmonary scars or fibrosis.

Adenocarcinoma is most commonly located in the lung periphery. This is in contrast to small cell carcinoma and squamous cell carcinoma, which tend to be located in the central portions of the lung.

Adenocarcinoma is associated with activating mutations including Kirsten Rat Sarcoma Viral Oncogene Homologue (KRAS), Epidermal Growth Factor Receptor (EGFR) and Anaplastic Lymphoma Kinase (ALK). It is important to analyze tumor tissue for the presence of these mutations since there are drugs that target and inhibit the specific molecular pathways in the malignant cells.

The characteristic histology for adenocarcinoma is gland formation. Histological diagnosis requires evidence of either neoplastic gland formation or intracytoplasmic mucin.

Adenocarcinoma tends to stain mucin positive since it is derived from the mucus producing glands of the lung.

Hemoptysis is the coughing up of blood or blood-tinged sputum from the lungs, bronchi, trachea or larynx. Hemoptysis can be a symptom of cancer, bronchiectasis, and pulmonary embolism or infections such as pneumonia, tuberculosis or bronchitis.

Digital clubbing is a deformity characterized by increased distal finger tip mass and increased nail plate curvature. The Lovibond angle, the angle between the nail plate and the proximal nail fold when viewed for the side is greater than 180 degrees in clubbed nails, compared to 160 degrees in normal nails. There are many causes of clubbing, including pulmonary diseases.

Non-small cell lung cancers that present early in the disease process are generally treated upfront with surgical resection. Patients with metastatic disease outside of the chest are not candidates for surgical resection. Even with a complete resection, recurrence is still possible.

For patients who present early in the disease process, radiation therapy is an important adjunct to surgery. For patients who present in later stages, radiation and chemotherapy are the mainstays of treatment.