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===Extrapulmonary Small Cell Carcinoma===
===Extrapulmonary Small Cell Carcinoma===
Very rarely, the primary site for small cell carcinoma is outside of the lungs and pleural space, it is referred to as extrapulmonary small cell carcinoma (EPSCC). Outside of the respiratory tract, small cell carcinoma can appear in the cervix, prostrate, liver, pancreas, gastrointestinal tract. It is estimated to account for 1,000 new cases a year in the U.S. Histologically similar to small cell lung cancer, therapies for small cell lung cancer are usually used to treat EPSCC.<ref>{{EMedicine|article|284288|Extrapulmonary Small Cell Carcinoma}}</ref> First line treatment is usually with cisplatin and etoposide.
Very rarely, the primary site for small cell carcinoma is outside of the lungs and pleural space, it is referred to as extrapulmonary small cell carcinoma (EPSCC). Outside of the respiratory tract, small cell carcinoma can appear in the cervix, prostate, liver, pancreas, gastrointestinal tract. It is estimated to account for 1,000 new cases a year in the U.S. Histologically similar to small cell lung cancer, therapies for small cell lung cancer are usually used to treat EPSCC.<ref>{{EMedicine|article|284288|Extrapulmonary Small Cell Carcinoma}}</ref> First line treatment is usually with cisplatin and etoposide.


When the primary site is in the skin, it is referred to as [[Merkel cell carcinoma]].
When the primary site is in the skin, it is referred to as [[Merkel cell carcinoma]].

Revision as of 04:40, 5 May 2012

Small-cell carcinoma
SpecialtyOncology Edit this on Wikidata

Small cell carcinoma (sometimes known as "small-cell carcinoma", "small cell lung cancer", or "Oat-cell carcinoma") is a type of highly malignant cancer that most commonly arises within the lung,[1] although it can occasionally arise in other body sites, such as the cervix,[2] prostate,[3] and gastrointesinal tract.

Pie chart showing incidence of small cell lung cancer (shown in red at right), as compared to other lung cancer types, with fractions of smokers versus smokers shown for each type.[4]

Histopathology

Small cell carcinoma is an undifferentiated neoplasm composed of primitive-appearing cells.

As the name implies, small cell carcinomas are smaller than normal cells, and barely have room for any cytoplasm. Some researchers identify this as a failure in the mechanism that controls the size of the cells.[5]

Paraneoplastic Syndromes

In a significant number of cases, small cell carcinomas can produce ectopic hormones, including adrenocorticotropic hormone (ACTH) and anti-diuretic hormone (ADH). Ectopic production of large amounts of ADH leads to syndrome of inappropriate production of anti-diuretic hormone (SIADH).

Lambert-Eaton myasthenic syndrome (LEMS) is a well-known paraneoplastic condition linked to small cell carcinoma.[6]

Lung

Histopathologic image of small cell carcinoma of the lung. CT-guided core needle biopsy. H&E stain.

When associated with the lung, it is sometimes called "oat cell carcinoma" due to the flat cell shape and scanty cytoplasm.

It is thought to originate from neuroendocrine cells (APUD cells) in the bronchus called Feyrter cells (named for Friedrich Feyrter).[7] Hence, they express a variety of neuroendocrine markers, and may lead to ectopic production of hormones like ADH and ACTH that may result in paraneoplastic syndromes and Cushing's syndrome.[8] Approximately half of all individuals diagnosed with Lambert-Eaton myasthenic syndrome (LEMS) will eventually be found to have a small cell carcinoma of the lung.[6]

Small cell carcinoma is most often more rapidly and widely metastatic than non-small cell lung carcinoma[9] (and hence staged differently). There is usually early involvement of the hilar and mediastinal lymph nodes. [8]

Combined small cell lung carcinoma (c-SCLC)

Main article: Combined small cell lung carcinoma

Small cell lung carcinoma can occur in combination with a wide variety of other histological variants of lung cancer,[10] including extremely complex malignant tissue admixtures.[11] .[12] When it is found with one or more differentiated forms of lung cancer, such as squamous cell carcinoma or adenocarcinoma, the malignant tumor is then diagnosed and classified as a combined small cell lung carcinoma (c-SCLC).[10] C-SCLC is the only currently recognized subtype of SCLC.[10]

Although combined small cell lung carcinoma is currently staged and treated similarly to "pure" small cell carcinoma of the lung, recent research suggests surgery might improve outcomes in very early stages of this tumor type.

Smoking is a significant etiological factor.

Symptoms and signs are as for other lung cancers. In addition, because of their neuroendocrine cell origin, small cell carcinomas will often secrete substances that result in paraneoplastic syndromes such as Lambert-Eaton myasthenic syndrome.

Extrapulmonary Small Cell Carcinoma

Very rarely, the primary site for small cell carcinoma is outside of the lungs and pleural space, it is referred to as extrapulmonary small cell carcinoma (EPSCC). Outside of the respiratory tract, small cell carcinoma can appear in the cervix, prostate, liver, pancreas, gastrointestinal tract. It is estimated to account for 1,000 new cases a year in the U.S. Histologically similar to small cell lung cancer, therapies for small cell lung cancer are usually used to treat EPSCC.[13] First line treatment is usually with cisplatin and etoposide.

When the primary site is in the skin, it is referred to as Merkel cell carcinoma.

Small cell carcinoma of the prostate

In the prostate, small cell carcinoma (SCCP) is a rare form of cancer (approx 1% of PC).[14] Due to the fact that there is little variation in prostate specific antigen levels, this form of cancer is normally diagnosed at an advanced stage, after metastasis.

It can metastasize to the brain.[15]

Treatment for small cell lung carcinoma

Small cell lung carcinoma has long been divided into two clinicopathological stages, including limited stage (LS) and extensive stage (ES). The stage is generally determined by the presence or absence of metastases, whether or not the tumor appears limited to the thorax, and whether or not the entire tumor burden within the chest can feasibly be encompassed within a single radiotherapy portal.[16]

In cases of LS-SCLC, combination chemotherapy (often including cyclophosphamide, cisplatinum, doxorubicin, etoposide, vincristine and/or paclitaxel) is administered together with concurrent chest radiotherapy (RT).

Chest RT has been shown to improve survival in LS-SCLC.

Exceptionally high objective initial response rates (RR) of between 60% and 90% are seen in LS-SCLC using chemotherapy alone, with between 45% and 75% of individuals showing a "complete response" (CR), which is defined as the disappearance of all radiological and clinical signs of tumor. Unfortunately, relapse is the rule, and median survival is only 18 to 24 months.

Because SCLC usually metastasizes widely very early on in the natural history of the tumor, and because nearly all cases respond dramatically to CT and/or RT, there has been little role for surgery in this disease since the 1970s.[17] However, recent work suggests that in cases of small, asymptomatic, node-negative SCLC's ("very limited stage"), surgical excision may improve survival when used prior to chemotherapy.("adjuvant chemotherapy").[18]

In ES-SCLC, combination chemotherapy is the standard of care, with radiotherapy added only to palliate symptoms such as dyspnea, pain from liver or bone metastases, or for treatment of brain metastases, which, in small cell lung carcinoma, typically have a rapid, if temporary, response to whole brain radiotherapy.

Combination chemotherapy consists of a wide variety of agents, including cisplatin, cyclophosphamide, vincristine and carboplatin. Response rates are high even in extensive disease, with between 15% and 30% of subjects having a complete response to combination chemotherapy, and the vast majority having at least some objective response. Responses in ES-SCLC are often of short duration, however.

If complete response to chemotherapy occurs in a subject with SCLC, then prophylactic cranial irradiation (PCI) is often used in an attempt to prevent the emergence of brain metastases. Although this treatment is often effective, it can cause hair loss and fatigue. Prospective randomized trials with almost two years follow-up have not shown neurocognitive ill-effects. Meta-analyses of randomized trials confirm that PCI provides significant survival benefits.

All in all, small cell carcinoma is very responsive to chemotherapy and radiotherapy, and in particular, regimens based on platinum-containing agents. However, most people with the disease relapse, and median survival remains low.

Prognosis

In limited stage disease, median survival with treatment is 14–20 months, and about 20% of patients with limited stage small cell lung carcinoma live 5 years or longer.

The prognosis is far worse in extensive stage small cell lung carcinoma, with treatment, median survival is just 8–13 months, and only 1–5% of patients with extensive stage small cell lung carcinoma treated with chemotherapy live 5 years or longer.

See also

References

  1. ^ "small-cell carcinoma" at Dorland's Medical Dictionary
  2. ^ Nasu K, Hirakawa T, Okamoto M; et al. (2011). "Advanced small cell carcinoma of the uterine cervix treated by neoadjuvant chemotherapy with irinotecan and cisplatin followed by radical surgery". Rare Tumors. 3 (1): e6. doi:10.4081/rt.2011.e6. PMC 3070456. PMID 21464879. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  3. ^ Capizzello A, Peponi E, Simou N; et al. (2011). "Pure small cell carcinoma of the prostate: a case report and literature review". Case Rep Oncol. 4 (1): 88–95. doi:10.1159/000324717. PMC 3072185. PMID 21475596. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  4. ^ Smokers defined as current or former smoker of more than 1 year of duration. See image page in Commons for percentages in numbers. Reference:
  5. ^ Leslie M (2011). "Mysteries of the cell. How does a cell know its size?". Science. 334 (6059): 1047–8. doi:10.1126/science.334.6059.1047. PMID 22116854. {{cite journal}}: Unknown parameter |month= ignored (help)
  6. ^ a b Titulaer MJ, Verschuuren JJ (2008). "Lambert-Eaton myasthenic syndrome: tumor versus nontumor forms". Ann. N. Y. Acad. Sci. 1132: 129–34. doi:10.1196/annals.1405.030. PMID 18567862.
  7. ^ Champaneria MC, Modlin IM, Kidd M, Eick GN (2006). "Friedrich Feyrter: a precise intellect in a diffuse system". Neuroendocrinology. 83 (5–6): 394–404. doi:10.1159/000096050. PMID 17028417.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. ^ a b Mitchell, Richard Sheppard; Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson. "Ch. 13, box on morphology of small cell lung carcinoma". Robbins Basic Pathology (8th ed.). Philadelphia: Saunders. ISBN 1-4160-2973-7.{{cite book}}: CS1 maint: multiple names: authors list (link)
  9. ^ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease. St. Louis, Mo: Elsevier Saunders. p. 759. ISBN 0-7216-0187-1.{{cite book}}: CS1 maint: multiple names: authors list (link)
  10. ^ 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 92 832 2418 3. Retrieved 27 March 2010.
  11. ^ Pelosi G, Sonzogni A, Galetta D; et al. (2011). "Combined small-cell carcinoma of the lung with quadripartite differentiation of epithelial, neuroendocrine, skeletal muscle, and myofibroblastic type". Virchows Arch. 458 (4): 497–503. doi:10.1007/s00428-010-1011-8. PMID 21210145. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  12. ^ Gotoh M, Yamamoto Y, Huang CL, Yokomise H (2004). "A combined small cell carcinoma of the lung containing three components: small cell, spindle cell and squamous cell carcinoma". Eur J Cardiothorac Surg. 26 (5): 1047–9. doi:10.1016/j.ejcts.2004.08.002. PMID 15519208. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  13. ^ Extrapulmonary Small Cell Carcinoma at eMedicine
  14. ^ Nutting C, Horwich A, Fisher C, Parsons C, Dearnaley DP (1997). "Small cell carcinoma of the prostate". Journal of the Royal Society of Medicine. 90 (6): 340–1. PMC 1296316. PMID 9227387. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  15. ^ Erasmus CE, Verhagen WI, Wauters CA, van Lindert EJ (2002). "Brain metastasis from prostate small cell carcinoma: not to be neglected". Can J Neurol Sci. 29 (4): 375–7. PMID 12463494. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  16. ^ Argiris A, Murren JR (2001). "Staging and clinical prognostic factors for small-cell lung cancer". Cancer J. 7 (5): 437–47. PMID 11693903.
  17. ^ Mountain CF (1978). "Clinical biology of small cell carcinoma: relationship to surgical therapy". Semin. Oncol. 5 (3): 272–9. PMID 211638. {{cite journal}}: Unknown parameter |month= ignored (help)
  18. ^ Shepherd FA (2010). "Surgery for limited stage small cell lung cancer: time to fish or cut bait". J Thorac Oncol. 5 (2): 147–9. doi:10.1097/JTO.0b013e3181c8cbf5. PMID 20101141. {{cite journal}}: Unknown parameter |month= ignored (help)

Additional images

  • Anaplastic (microcellular, oat cell) carcinoma from the lung (histopathology)
    Anaplastic (microcellular, oat cell) carcinoma from the lung (histopathology)
  • Histopathologic image of small cell carcinoma of the lung. CT-guided core needle biopsy.
    Histopathologic image of small cell carcinoma of the lung. CT-guided core needle biopsy.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Small-cell_carcinoma&oldid=490741656"