Metaplastic Breast Carcinoma: Clinicopathological Parameters and Prognostic Profile

Saroona Haroon; Shamail Zia; Umme Aiman Shirazi; Omer Ahmed; Ishaq Azeem Asghar; Muhammad Asad Diwan; Anoshia Afzal; Muhammad Irfan; Syed Jawwad Ali; Atif A Hashmi

doi:10.7759/cureus.14347

Metaplastic Breast Carcinoma: Clinicopathological Parameters and Prognostic Profile

Cureus. 2021 Apr 7;13(4):e14347. doi: 10.7759/cureus.14347.

Authors

Saroona Haroon^{1

2}, Shamail Zia³, Umme Aiman Shirazi⁴, Omer Ahmed⁵, Ishaq Azeem Asghar⁶, Muhammad Asad Diwan⁷, Anoshia Afzal⁸, Muhammad Irfan⁹, Syed Jawwad Ali¹⁰, Atif A Hashmi⁴

Affiliations

¹ Pathology, King's Mill Hospital - Sherwood Forest Hospitals, National Health Service (NHS) Foundation Trust, Ashfield, GBR.
² Pathology, Prince Faisal Oncology Centre, King Fahad Specialist Hospital, Buraidah, SAU.
³ Pathology, Ziauddin University, Karachi, PAK.
⁴ Pathology, Liaquat National Hospital and Medical College, Karachi, PAK.
⁵ Internal Medicine, Liaquat National Hospital and Medical College, Karachi, PAK.
⁶ Pathology, Ascension St. John Hospital, Detroit, USA.
⁷ Pathology, Aga Khan University, Karachi, PAK.
⁸ Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
⁹ Statistics, Liaquat National Hospital and Medical College, Karachi, PAK.
¹⁰ Pathology, Dow University of Health Sciences, Karachi, PAK.

Abstract

Introduction Metaplastic breast carcinoma (MBC) is defined as breast cancer with a heterologous non-glandular component. MBC is considered a special type of breast cancer with a prognosis that is worse than invasive ductal carcinoma (IDC) of the breast. MBC is the most common breast cancer with a triple-negative profile. Therefore, in this study, we evaluated the clinicopathological parameters, recurrence and survival of MBC in our population. Methods We conducted a retrospective observational study in the Department of Histopathology at Prince Faisal Oncology Centre, Buraidah, Saudi Arabia, over a period of five years. All cases diagnosed as MBC were included in the study. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2/neu) immunohistochemistry (IHC) was performed on representative tissue blocks. Results Total 183 cases of MBCs were included in the study, out of which 120 cases were excision specimens. The mean age of the patients was 48.84±12.99 years, and the most common age group was between 36 and 50 years of age. Most of the cases were tumor (T) stage T3 (50%), and nodal metastasis was present in 40% of cases. Most cases were grade III (78.7%). ER, PR and HER2/neu positivity was noted in 15.8%, 13.1%, and 9.8% cases, respectively. Follow-up data were available for 70 cases, with a median follow-up period of 4 (1-7) years. Tumor recurrence was noted in 31.4% cases, with a survival rate of 71.4%. Squamous, chondroid, spindle cell differentiation, and matrix production were noted in 70.5%, 7.1%, 13.7%, and 2.2% cases, respectively. A significant association of squamous differentiation was noted with HER2/neu positivity. An inverse association of spindle cell differentiation was seen with axillary metastasis. Survival analysis by Kaplan-Meier revealed a significant association of survival with tumor recurrence. Conclusion MBC is an important subtype of breast cancer, histopathological identification of which is challenging, owing to varied histological differentiation. We found squamous differentiation to be the most common in MBC, which was associated with HER2/neu positivity. A high recurrence rate of MBC was also observed in our study that was significantly associated with survival.

Keywords: breast cancer; estrogen receptor; human epidermal growth factor receptor 2; immunohistochemistry; metaplastic breast carcinoma; progesterone receptor.