LUNG CANCER:

Divided in two main categories: Small cell lung carcinoma and non-small cell carcinoma (NSCLC), the latter is divided further into adenocarcinoma, squamous cell carcinoma, and large cell carcionama according to its histological characteristics.

Small cel carcinoma (oat cell): central location, undifferenciated, exhibits aggressive behavior, with rapid growth, early spread to distant sites, exquisite sensitivity to chemotherapy and radiation, and frequent associated with distint paraneoplastic syndromes (Tan, 2011). May lead to Lambert-Eaton syndrome. It is considered inoperable (Le, Bhushan, Tolles, & Hofmann, 2011) surgery usually plays no role in its management except in rare situactions (Schreiber, Rinner, & Vongtama, 2008).

Histology: neoplasm of neuroendocrine Kulchitsy cells (small dark blue cells).

Squamous cell carcinoma: located central, hiliar mass arising from brochus, cavitation; tendency to spread to regional lymph nodes and has clearly linked to smoking (Navarro & Arroyo, 2007) (Le at el, 2011)Parathyroid-like activities(PTHrP).

Histology:Keratin pearls and intracellular bridges.

Adenocarcinoma: arise from the mucus glands or from any epithelial cell within  or distal to the terminal bronchioles, usually present as peripheral nodules or masses (Tierney, McPhee, & Papadakis, 2005), 2 types:

1)    Bronchial: develop in site prior pulmonary inflammation or injuty; most common lung cancer in Nonsmoker and female.

2)    Broncho-alveolar: Not linked to smoking, grows along airway, can present like pneumonia, can results in hypertrophic osteoarthropathy.

Histology: (both) Clara cell---type II pneumocytes.

Large cell carcinoma: peripheral location, highly anaplastic undifferenciated tumor with rapid doubling time and aggressive clinical course (Tierney at el, 2005), poor prognosis, less responsive to chemotherapy but it is removed surgically (Le al el, 2011).

Histology: pleomorphic giant cell with leukocytes fragments in cytoplasm.

Carcinoid tumor: secrets serotonin can cause carcinoid syndrome, fibrous deposit in right heart valve may lead to tricuspid insufficiency, pulmonary stenosis, and right heart failure.

Mesothelioma: pleural location, malignancy of the pleura associated with asbestosis, but not all cases are associated with asbesto exposure (Hodgson & Darnton, 2000) according Winston W Tan, MD.  Results in hemorrhage pleural effusion, and pleural thinckening (Le at el, 2011). Mesothelioma is most common in males, and occurs most commonly in the fifth-seventh decades of life (Tan, 2011).

Histology: Psammoma bodies.

Lung cancer complications:

1)    Superior Vena Cava syndrome

2)    Pancoast’s tumor

3)    Horner’s syndrome

4)    Paraneoplastic endocrine manifestation

5)    Recurrent Laryngeal simptoms (hoarseness)

6)    Pleural and pericardial effusions.

Metastases to lung is most common, often from breast, colon, prostate,

and bladder cancer.

         Sites of metastases: adrenal, brain, bone, and liver.

Bibliography

Hodgson, J., & Darnton, A. (2000). The quantitative risk of mesothelioma and lung cancer in relation to asbestos exposure. Ann Occup Hyg. Dec , 44 (8):565-601.

Le, T., Bhushan, V., Tolles, J., & Hofmann, J. (2011). First AID for the USMLE step 1. usa: McGraw Hill.

Navarro, F., & Arroyo, M. (2007). Cancer de Pulmon. In Cliniguia actualizacion de diagnostico y tratamiento (pp. 861-867). Spain: EviScience publicaciones.

Schreiber, D., Rinner, J., & Vongtama, D. (2008). Surgery for limited-stage small cell lung cancer, should the paradigm shift? A SEER-based analysis. J Clin Oncol (Sppl) , 26:403s.

Tan, W. W. (2011, Nov 16). Medscape.com. Retrieved Feb 3, 2012, from small cell lung cancer: http://emedicine.medscape.com/article/280104-overview

Tierney, L. M., McPhee, S. J., & Papadakis, M. A. (2005). CURRENT medical diagnosis & treatment. usa: McGraw Hill.