Expression of α-smooth muscle actin in benign and malignant salivary gland tumors: An immunohistochemical study

Mahalakshmi Ravi, Karen Boaz, Srikant Natarajan, Amitha Lewis, Mukul Prasad, Swetha Yellapurkar

Research output: Contribution to journalArticle

Abstract

Background and Objectives: Myoepithelial cells (ME) are known to contribute in the patterning of salivary gland neoplasms (SGN) and possess cytoplasmic smooth muscle actin (SMA) revealed by alpha SMA (α-SMA). The present study aimed to assess the expression of α-SMA in selected benign and malignant SGN (pleomorphic adenoma [PA], mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and polymorphous low-grade adenocarcinoma (PLGA). Materials and Methods: The intensity and pattern of expression of α-SMA were studied in 25 cases of SGN's ACC (n = 7), MEC (n = 8), PA (n = 8), and PLGA (n = 2), and correlated with the histological patterns. Results: Maximum expression of α-SMA in the epithelial compartment was seen in ACC, followed by PA, whereas MEC and PLGA showed completely negative staining. The connective tissue expression was mild in ACC and MEC. The myxoid stroma of PA with 'melting' pattern was weakly positive for α-SMA. The stroma in PLGA showed complete negativity. In ACC, α-SMA-positive cells were lining the cribriform spaces, small islands, and dispersed within large islands. Small nests showed complete positivity for α-SMA. Interpretation and Conclusion: In ACC, α-SMA expression supports the involvement of ME in epithelial organization explaining the histological patterns seen. In PA, the expression correlates with the predominantly secretory nature of ME. The absence of epithelial positivity in MEC and PLGA suggest that ME has less role to play in their histogenesis. The weak stromal positivity observed in MEC and ACC may be attributed to the positive immunoreactivity of myofibroblasts playing a role in modulating the course of SGN's.

Original languageEnglish
Pages (from-to)479-484
Number of pages6
JournalIndian Journal of Pathology and Microbiology
Volume61
Issue number4
DOIs
Publication statusPublished - 01-10-2018

Fingerprint

Glandular and Epithelial Neoplasms
Adenoid Cystic Carcinoma
Mucoepidermoid Carcinoma
Smooth Muscle
Actins
Pleomorphic Adenoma
Adenocarcinoma
Salivary Gland Neoplasms
Islands
Negative Staining
Myofibroblasts
Connective Tissue
Freezing
Epithelial Cells

All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine
  • Microbiology (medical)

Cite this

@article{3ca62bde834b4561945474c95608e8d5,
title = "Expression of α-smooth muscle actin in benign and malignant salivary gland tumors: An immunohistochemical study",
abstract = "Background and Objectives: Myoepithelial cells (ME) are known to contribute in the patterning of salivary gland neoplasms (SGN) and possess cytoplasmic smooth muscle actin (SMA) revealed by alpha SMA (α-SMA). The present study aimed to assess the expression of α-SMA in selected benign and malignant SGN (pleomorphic adenoma [PA], mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and polymorphous low-grade adenocarcinoma (PLGA). Materials and Methods: The intensity and pattern of expression of α-SMA were studied in 25 cases of SGN's ACC (n = 7), MEC (n = 8), PA (n = 8), and PLGA (n = 2), and correlated with the histological patterns. Results: Maximum expression of α-SMA in the epithelial compartment was seen in ACC, followed by PA, whereas MEC and PLGA showed completely negative staining. The connective tissue expression was mild in ACC and MEC. The myxoid stroma of PA with 'melting' pattern was weakly positive for α-SMA. The stroma in PLGA showed complete negativity. In ACC, α-SMA-positive cells were lining the cribriform spaces, small islands, and dispersed within large islands. Small nests showed complete positivity for α-SMA. Interpretation and Conclusion: In ACC, α-SMA expression supports the involvement of ME in epithelial organization explaining the histological patterns seen. In PA, the expression correlates with the predominantly secretory nature of ME. The absence of epithelial positivity in MEC and PLGA suggest that ME has less role to play in their histogenesis. The weak stromal positivity observed in MEC and ACC may be attributed to the positive immunoreactivity of myofibroblasts playing a role in modulating the course of SGN's.",
author = "Mahalakshmi Ravi and Karen Boaz and Srikant Natarajan and Amitha Lewis and Mukul Prasad and Swetha Yellapurkar",
year = "2018",
month = "10",
day = "1",
doi = "10.4103/IJPM.IJPM_482_17",
language = "English",
volume = "61",
pages = "479--484",
journal = "Indian Journal of Pathology and Microbiology",
issn = "0377-4929",
publisher = "Medknow Publications and Media Pvt. Ltd",
number = "4",

}

Expression of α-smooth muscle actin in benign and malignant salivary gland tumors : An immunohistochemical study. / Ravi, Mahalakshmi; Boaz, Karen; Natarajan, Srikant; Lewis, Amitha; Prasad, Mukul; Yellapurkar, Swetha.

In: Indian Journal of Pathology and Microbiology, Vol. 61, No. 4, 01.10.2018, p. 479-484.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Expression of α-smooth muscle actin in benign and malignant salivary gland tumors

T2 - An immunohistochemical study

AU - Ravi, Mahalakshmi

AU - Boaz, Karen

AU - Natarajan, Srikant

AU - Lewis, Amitha

AU - Prasad, Mukul

AU - Yellapurkar, Swetha

PY - 2018/10/1

Y1 - 2018/10/1

N2 - Background and Objectives: Myoepithelial cells (ME) are known to contribute in the patterning of salivary gland neoplasms (SGN) and possess cytoplasmic smooth muscle actin (SMA) revealed by alpha SMA (α-SMA). The present study aimed to assess the expression of α-SMA in selected benign and malignant SGN (pleomorphic adenoma [PA], mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and polymorphous low-grade adenocarcinoma (PLGA). Materials and Methods: The intensity and pattern of expression of α-SMA were studied in 25 cases of SGN's ACC (n = 7), MEC (n = 8), PA (n = 8), and PLGA (n = 2), and correlated with the histological patterns. Results: Maximum expression of α-SMA in the epithelial compartment was seen in ACC, followed by PA, whereas MEC and PLGA showed completely negative staining. The connective tissue expression was mild in ACC and MEC. The myxoid stroma of PA with 'melting' pattern was weakly positive for α-SMA. The stroma in PLGA showed complete negativity. In ACC, α-SMA-positive cells were lining the cribriform spaces, small islands, and dispersed within large islands. Small nests showed complete positivity for α-SMA. Interpretation and Conclusion: In ACC, α-SMA expression supports the involvement of ME in epithelial organization explaining the histological patterns seen. In PA, the expression correlates with the predominantly secretory nature of ME. The absence of epithelial positivity in MEC and PLGA suggest that ME has less role to play in their histogenesis. The weak stromal positivity observed in MEC and ACC may be attributed to the positive immunoreactivity of myofibroblasts playing a role in modulating the course of SGN's.

AB - Background and Objectives: Myoepithelial cells (ME) are known to contribute in the patterning of salivary gland neoplasms (SGN) and possess cytoplasmic smooth muscle actin (SMA) revealed by alpha SMA (α-SMA). The present study aimed to assess the expression of α-SMA in selected benign and malignant SGN (pleomorphic adenoma [PA], mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and polymorphous low-grade adenocarcinoma (PLGA). Materials and Methods: The intensity and pattern of expression of α-SMA were studied in 25 cases of SGN's ACC (n = 7), MEC (n = 8), PA (n = 8), and PLGA (n = 2), and correlated with the histological patterns. Results: Maximum expression of α-SMA in the epithelial compartment was seen in ACC, followed by PA, whereas MEC and PLGA showed completely negative staining. The connective tissue expression was mild in ACC and MEC. The myxoid stroma of PA with 'melting' pattern was weakly positive for α-SMA. The stroma in PLGA showed complete negativity. In ACC, α-SMA-positive cells were lining the cribriform spaces, small islands, and dispersed within large islands. Small nests showed complete positivity for α-SMA. Interpretation and Conclusion: In ACC, α-SMA expression supports the involvement of ME in epithelial organization explaining the histological patterns seen. In PA, the expression correlates with the predominantly secretory nature of ME. The absence of epithelial positivity in MEC and PLGA suggest that ME has less role to play in their histogenesis. The weak stromal positivity observed in MEC and ACC may be attributed to the positive immunoreactivity of myofibroblasts playing a role in modulating the course of SGN's.

UR - http://www.scopus.com/inward/record.url?scp=85054778382&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85054778382&partnerID=8YFLogxK

U2 - 10.4103/IJPM.IJPM_482_17

DO - 10.4103/IJPM.IJPM_482_17

M3 - Article

C2 - 30303133

AN - SCOPUS:85054778382

VL - 61

SP - 479

EP - 484

JO - Indian Journal of Pathology and Microbiology

JF - Indian Journal of Pathology and Microbiology

SN - 0377-4929

IS - 4

ER -