title: Histochemical analysis and immunohistochemical profile of mucoepidermoid carcinoma of the conjunctiva.
abstract: OBJECTIVE
  To elucidate the distinct histochemical and immunohistochemical profile of mucoepidermoid carcinoma of the conjunctiva (MECC) and to determine which combination of stains is most useful in diagnosing MECC and differentiating it from squamous cell carcinoma of the conjunctiva (SCC) in cases where the clinical or cytological findings are not definitive.
  
  
  METHODS
  Eight specimen of MECC from 4 patients and 4 specimens of SCC from 4 patients were examined using a variety of special stains and immunohistochemical markers. The results were then analyzed for usefulness in diagnosing MECC.
  
  
  RESULTS
  The most useful markers in diagnosing MECC and differentiating it from SCC are mucicarmine, colloidal iron, and alcian blue all with sensitivities of 88%, and a specificity of 100%; CEA with a sensitivity of 83% and a specificity of 75%; and, mucin-1 with a sensitivity of 100% and a specificity of 25%, but which showed a distinct pattern of staining of MECC when compared to SCC. In our series, the sensitivity of the CK7+/CK20- combination for MECC was only 38%.
  
  
  CONCLUSIONS
  The most useful stains in ruling out SCC in a suspected case of MECC were shown to be mucicarmine and the glycosaminoglycan (GAG) stains. However, in cases where mucicarmine and the GAG stains are negative or difficult to interpret and there is suspicion of a diagnosis of MECC, CEA and mucin-1 may be helpful for this diagnosis. The findings of CK7+/CK20- also may be of assistance, but are not as sensitive when compared to analogous salivary gland lesions, when differentiating MECC from SCC.
authors: Department of Ophthalmology, The Ottawa Hospital and the University of Ottawa, Ottawa, Ontario, Canada ; Department of Pathology, The Ottawa Hospital and the University of Ottawa, Ottawa, Ontario, Canada.
authors: André
authors: A
authors: Jastrzebski
authors: Seymour
authors: S
authors: Brownstein
authors: David R
authors: DR
authors: Jordan
authors: Steven M
authors: SM
authors: Gilberg
keywords: Conjunctiva; Histochemical stains; Immunohistochemistry; Mucoepidermoid carcinoma
references: Kyobu Geka. 2005 Jul;58(7):592-5
references: 16004345
references: Int J Pediatr Otorhinolaryngol. 2004 Jul;68(7):895-902
references: 15183580
references: Am J Ophthalmol. 1999 Nov;128(5):640-3
references: 10577538
references: Yan Ke Xue Bao. 2005 Sep;21(3):152-7
references: 17162853
references: Surv Ophthalmol. 2006 Sep-Oct;51(5):513-9
references: 16950250
references: Ophthalmology. 1981 Dec;88(12):1226-30
references: 7322472
references: Cancer. 1976 Oct;38(4):1699-709
references: 991088
references: Ophthalmic Plast Reconstr Surg. 1994 Sep;10(3):163-8
references: 7947443
references: Int Ophthalmol. 2009 Oct;29(5):401-9
references: 18784902
references: Arch Ophthalmol. 1984 May;102(5):730-1
references: 6721766
references: Int J Gynecol Pathol. 1985;4(4):314-27
references: 3002994
references: Ophthalmology. 2000 Apr;107(4):801-5
references: 10768346
references: Histopathology. 2007 Jul;51(1):26-32
references: 17593078