Adenosquamous lung carcinoma

Adenosquamous lung carcinoma
SpecialtyOncology/pulmonology

Adenosquamous lung carcinoma (AdSqLC) is a biphasic malignant tumor arising from lung tissue that is composed of at least 10% by volume each of squamous cell carcinoma (SqCC) and adenocarcinoma (AdC) cells.[1]

Classification

Lung cancers have been historically classified using two major paradigms. Histological classification systems group lung cancers according to the appearance of the cells and surrounding tissues when they are viewed under a microscope. Clinical classification systems divide lung cancers into groups based on medical criteria, particularly their response to different treatment regimens.

Before the mid-1900s, lung cancer was considered to be a single disease entity, with all forms treated similarly. In the 1960s, small cell lung carcinoma (SCLC) was recognized as a unique form of lung cancer, based both on its appearance (histology) and its clinical properties, including much greater susceptibility to chemotherapy and radiation, more rapid growth rate, and its propensity to metastasize widely early on in its course. Since then, most oncologists have based patient treatment decisions on a dichotomous division of lung cancers into SCLC and non-small cell lung carcinomas (NSCLC), with the former being treated primarily with chemoradiation, and the latter with surgery.

An explosion of new knowledge, accumulated mainly over the last 20 years, has proved that lung cancers should be considered an extremely heterogeneous family of neoplasms[2] with widely varying genetic, biological, and clinical characteristics, particularly their responsiveness to the large number of newer treatment protocols. Well over 50 different histological variants are now recognized under the 2004 revision of the World Health Organization ("WHO-2004") typing system, currently the most widely used lung cancer classification scheme.[1] Recent studies have shown beyond doubt that the old clinical classification paradigm of "SCLC vs. NSCLC" is now obsolete, and that correct "subclassification" of lung cancer cases is necessary to assure that lung cancer patients receive optimum management.[3][4]

Approximately 98% of lung cancers are carcinoma, which are tumors composed of cells with epithelial characteristics.[5] LCLC's are one of 8 major groups of lung carcinomas recognized in WHO-2004:[1]

References

  1. ^ a b c Travis, William D; Brambilla, Elisabeth; Muller-Hermelink, H Konrad; Harris, Curtis C, eds. (2004). Pathology and Genetics of Tumours of the Lung, Pleura, Thymus and Heart (PDF). World Health Organization Classification of Tumours. Lyon: IARC Press. ISBN 978-92-832-2418-1. Archived from the original (PDF) on 23 August 2009. Retrieved 27 March 2010.
  2. ^ Roggli VL, Vollmer RT, Greenberg SD, McGavran MH, Spjut HJ, Yesner R (June 1985). "Lung cancer heterogeneity: a blinded and randomized study of 100 consecutive cases". Hum. Pathol. 16 (6): 569–79. doi:10.1016/S0046-8177(85)80106-4. PMID 2987102.
  3. ^ Rossi G, Marchioni A, Sartori G, Longo L, Piccinini S, Cavazza A (2007). "Histotype in non-small cell lung cancer therapy and staging: The emerging role of an old and underrated factor". Curr Respir Med Rev. 3: 69–77. doi:10.2174/157339807779941820.
  4. ^ Vincent MD (August 2009). "Optimizing the management of advanced non-small-cell lung cancer: a personal view". Curr Oncol. 16 (4): 9–21. doi:10.3747/co.v16i4.465. PMC 2722061. PMID 19672420.
  5. ^ Travis WD, Travis LB, Devesa SS (January 1995). "Lung cancer". Cancer. 75 (1 Suppl): 191–202. doi:10.1002/1097-0142(19950101)75:1+<191::AID-CNCR2820751307>3.0.CO;2-Y. PMID 8000996. S2CID 34718856.