Adenocarcinoma 237242 225735520 2008-07-15T03:53:16Z 96.33.66.64 {{Cleanup|date=May 2008}} {{DiseaseDisorder infobox | Name = Adenocarcinoma, NOS | ICD10 = | ICD9 = {{ICD9|151.0}}, {{ICD9|182.0}} | ICDO = {{ICDO|8140|3}} | Image = | Caption = | OMIM = | OMIM_mult = | MedlinePlus = | eMedicineSubj = | eMedicineTopic = | DiseasesDB = | MeshID = D000230 | }} '''Adenocarcinoma''' is a cancer that originates in [[glandular]] tissue. This tissue is also part of a larger tissue category known as [[epithelial]] tissue. Epithelial tissue includes skin, glands and a variety of other tissue that lines the cavities and organs of the body. [[Epithelial tissue|Epithelium]] is derived embryologically from [[ectoderm]], [[endoderm]] and [[mesoderm]]. To be classified as adenocarcinoma, the cells do not necessarily need to be part of a [[gland]], as long as they have secretory properties. This form of carcinoma can occur in some higher mammals, including humans.<ref>Fauquier, D.A., Gulland, F.M.D.,([[Marine Mammal Center]]), Haulena, M., Spraker, T., ‘’Biliary adenocarcinoma in a stranded [[Northern elephant seal]] (‘’Mirounga angustirortsis’‘)’‘, Journal of Wildlife Diseases 39(3):723-726 (2003)</ref> Well differentiated adenocarcinomas tend to resemble the glandular tissue that they are derived from, while poorly differentiated may not. By [[staining]] the cells from a biopsy, a pathologist will determine whether the tumor is an adenocarcinoma or some other type of cancer. Adenocarcinomas can arise in many tissues of the body due to the ubiquitous nature of glands within the body. While each gland may not be secreting the same substance, as long as there is an [[exocrine]] function to the cell, it is considered glandular and its malignant form is therefore named adenocarcinoma. [[Endocrine]] gland tumors, such as a [[VIPoma]], an [[insulinoma]], a [[pheochromocytoma]], etc, are typically not referred to as adenocarcinomas, but rather, are often called [[neuroendocrine tumors]]. If the glandular tissue is abnormal, but benign, it is said to be an [[adenoma]]. Benign adenomas typically do not invade other tissue and rarely [[metastasize]]. Malignant adenocarcinomas invade other tissues and often metastasize given enough time to do so. ==Diagnostic significance== A diagnosis of ''adenocarcinoma'' which is not further described, known as '''adenocarcinoma not otherwise specified''' and '''adenocarcinoma NOS''', is significant because it indicates a [[malignancy|cancerous process]] is present. However, it is not very useful for treatment decisions and prognosis, as these are determined by the tissue from which the tumour cells arose, i.e. the tissue of origin; an [[colon cancer|adenocarcinoma of the colon]] has a different prognosis and treatment than an [[ovarian cancer|adenocarcinoma of the ovary]]. Adenocarcinoma not otherwise specified is often a preliminary diagnosis and can frequently be clarified by a [[pathologist]] with the use of [[immunohistochemistry]].<ref>Dabbs DJ, Silverman JF. Immunohistochemical Workup of Metastatic Carcinoma of Unknown Primary. Pathology Case Reviews. 6(4):146-153, July/August 2001. [http://www.pathologycasereviews.com/pt/re/pathcr/abstract.00132583-200107000-00003.htm Abstract].</ref> Cancer for which a primary site cannot be found is called '''[[cancer of unknown primary]]'''. ==Histopathology== Examples of tissues where adenocarcinomas may arise: * [[breast]] * '''[[colon]]'''<br /> [[Image:Colon cancer.jpg|thumb|200px|right|[[Gross examination|Gross]] appearance of a [[colectomy]] specimen containing two [[Colorectal polyp|adenomatous polyps]] (the brownish oval tumors above the labels, attached to the normal beige lining by a stalk) and one '''invasive colorectal carcinoma''' (the crater-like, reddish, irregularly-shaped tumor located above the label).]][[Image:Colonic carcinoid (1) Endoscopic resection.jpg|thumb|Histopathologic image of colonic carcinoid stained by hematoxylin and eosin.]]The vast majority of [[colorectal cancer]] is an adenocarcinoma. This is because the colon had numerous glands within the tissue. Normal colonic glands tend to be simple and tubular in appearance with a mixture of [[mucus]] secreting [[goblet cells]] and water absorbing cells. These glands are called glands because they secrete a substance into the [[lumen]] of the colon, this substance being mucus. The purpose of these glands are twofold. The first is to absorb water from the feces back into the blood. The second purpose is to secrete mucus into the colon lumen to lubricate the now dehydrated feces. This is crucial as a failure to lubricate the feces can result in colonic damage by the feces as it passes towards the rectum. <ref>Young, Barbara, et al. "Wheater's Functional Histology, a Text and Color Atlas". 5 Ed. 2006. Pg 283. </ref> When these glands undergo a number of changes as the genetic level, they proceed in a normal and predictable manner as they move from benign to an invasive, malignant colon cancer. In the research paper, Vogelstein, et al, suggested that colon cells lose the [[APC]] tumor suppressor gene and become a small polyp. Next, they suggested that k-[[Ras]] becomes activated and the polyp becomes a small, benign, adenoma. The adenoma, lacking the "carcinoma" attached to the end of it, suggests that it is a benign version of the malignant adenocarcinoma. The gastroenterologist uses a colonoscopy to find and remove these adenomas and polyps to prevent them from continuing to acquire genetic changes that will lead to an invasive adenocarcinoma. Volgelstein et al went on to suggest that loss of the [[DCC]] gene and of [[p53]] result in a malignant adenocarcinoma. <ref>Vogelstein, et al. "Lessons from hereditary colo-recal cancer." Cell. 87: 159-170.</ref> Grossly, one will see a mass that looks of a different color than the surrounding tissue. Bleeding from the tumor is often apparent as the tumor tends to grow blood vessels into it in a haphazard manner via secretion of a number of [[angiogenesis]] promoting factors such as [[VEGF]]. Histologically, a glandular structure, similar to the healthy normal surrounding glands may be seen. If they look very similar, this is a low [[grade]], well differentiated tumor. Often these glands will be disorganized and they will be seen growing back to back. However, if the tumor does not look like a gland anymore, it is a high grade tumor with poor differentiation. Regardless of the grade, malignant tumors tend to have a large nucleus with prominent nucleoli. There will also be a noticeable increase in the incidence of [[mitoses]], or cell divisions. <br /> * '''[[lung]]'''non-small cell''' Currently, the most common type of lung cancer is the adenocarcinoma.<ref>Subramanian, J; Govindan R (February 2007). "Lung cancer in never smokers: a review". Journal of Clinical Oncology 25 (5): 561–570. American Society of Clinical Oncology. PMID 17290066</ref> This cancer usually is seen peripherally in the lungs, as opposed to [[small cell lung cancer]] and [[squamous cell]] lung cancer, which both tend to be more centrally located.<ref>Travis, WD; Travis LB, Devesa SS (January 1995). "Lung cancer". Cancer 75 (Suppl. 1): 191–202. PMID 8000996.</ref> The adenocarcinoma has an increased incidence in smokers, but is also the most common type of lung cancer seen in non-smokers. Adenocarcinoma of the lung tends to stain mucin positive as it is derived from the mucus producing glands of the lungs. 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).<ref>[http://radiology.uchc.edu/eAtlas/nav/msLung.htm Diseases of Lung<!-- Bot generated title -->]</ref>[http://radiology.uchc.edu/eAtlas/RESP/1624b.htm * [[prostate]] * [[stomach]] * '''[[pancreas]]''' (99% of pancreatic cancers are ductal adenocarcinomas<ref>Ananad MKN, Boylan C. Pancreas, Adenocarcinoma. eMedicine.com. URL: [http://www.emedicine.com/radio/topic516.htm http://www.emedicine.com/radio/topic516.htm]. Accessed on: January 27, 2008.</ref>) * [[cervix]] * [[vagina]] * [[urachus]] ==Etymology== The term adenocarcinoma is derived from 'adeno' meaning 'pertaining to a gland' and '[[carcinoma]]', which describes a cancer that has developed in the epithelial cells. ==References== {{Reflist}} {{ICDOMorphology}} [[Category:Types of cancer]] [[de:Adenokarzinom]] [[es:Adenocarcinoma]] [[fr:Adénocarcinome]] [[gl:Adenocarcinoma]] [[it:Adenocarcinoma]] [[la:Adenocarcinoma]] [[nl:Adenocarcinoom]] [[ja:腺癌]] [[pl:Gruczolakorak]] [[pt:Adenocarcinoma]] [[tr:Adenokarsinom]]