title: Comparison of Immunocytochemistry and Immunohistochemistry on Breast Carcinoma: A Boon or a Bane?
abstract: BACKGROUND
  Breast carcinoma is the most common cancer among women in the urban Indian population. Conventionally, immunohistochemistry (IHC) is done to determine the hormone receptor status of the tumor. Immunocytochemistry (ICC) on fine-needle aspiration cytology (FNAC) was carried out to determine the same hormone receptor status of the tumor.
  
  
  OBJECTIVE
  The study was undertaken to evaluate the diagnostic reliability of performing estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (Her2/neu) receptor status on FNAC by ICC and to compare the results with IHC.
  
  
  METHODS
  A 2 years 6 months prospective study conducted in the Department of Pathology, ESIC Medical College and PGIMSR and ESIC Model Hospital, Rajajinagar, Bengaluru, wherein 100 breast carcinoma patients' samples both cytology and histology were collected. IHC and ICC were done by peroxidase antiperoxidase technique. Validations of the receptor status were analyzed using sensitivity, specificity, positive and negative predictive values (PPV and NPV), and kappa statistics for agreements between ICC and IHC.
  
  
  RESULTS
  ICC was positive for ER, PR, and Her2/neu in 53, 50, and 22 cases, respectively. For ER, a cytohistologic correlation of 98%, with a sensitivity of 96.3%, specificity of 100%, and PPV and NPV being 100% and 95.7%. For PR, concordance of 97%, with a sensitivity of 94.3%, specificity of 100%, and PPV and NPV being 100% and 94%. Her2/neu had an agreement of 89%, with a sensitivity of 72%, specificity of 95.5%, and PPV and NPV being 85.7% and 90.1%.
  
  
  CONCLUSIONS
  ICC has been a boon and can be a paramount diagnostic adjunct to the routine investigations.
authors.affiliation: Department of Pathology, Belagavi Institute of Medical Sciences, Belagavi, Karnataka, India.
authors.forename: Kempula
authors.initials: K
authors.lastname: Geethamala
authors.affiliation: Department of Pathology, ESIC Medical College and PGIMSR, Rajajinagar, Bengaluru, Karnataka, India.
authors.forename: Venkataramappa Srinivasa
authors.initials: VS
authors.lastname: Murthy
authors.affiliation: Department of Pathology, ESIC Medical College and PGIMSR, Rajajinagar, Bengaluru, Karnataka, India.
authors.forename: Bangalore Ramalingiah
authors.initials: BR
authors.lastname: Vani
authors.affiliation: Department of Pathology, ESIC Medical College and PGIMSR, Rajajinagar, Bengaluru, Karnataka, India.
authors.forename: Madireddi Sudha
authors.initials: MS
authors.lastname: Rao
authors.affiliation: Department of Pathology, ESIC Medical College and PGIMSR, Rajajinagar, Bengaluru, Karnataka, India.
authors.forename: Malugnalli Uddappa
authors.initials: MU
authors.lastname: Thejaswini
authors.affiliation: Department of Pathology, ESIC Medical College and PGIMSR, Rajajinagar, Bengaluru, Karnataka, India.
authors.forename: Krishnarajapet Padmanabha
authors.initials: KP
authors.lastname: Padmaja
keywords: Breast carcinoma; immunocytochemistry; immunohistochemistry