Giant juvenile fibroadenoma in a 9-year-old: A case presentation and review of the current literature

Giant Juvenile Fibroadenoma: Case Report and Review of the Literature

Fibroadenomas are common benign breast tumors. Fibroadenomas that exceed 5 cm in diameter, weigh more than 500 g, or replace more than four-fifths of the breast are characterized as giant. A fibroadenoma diagnosed in patients during childhood or adolescence is characterized as juvenile. An extensive PubMed search of the literature in English up until August 2022 was performed. In addition, a rare case of a gigantic fibroadenoma in an 11-year-old premenarchal girl who was referred to our adolescent gynecology center is presented here. Eighty-seven cases of giant juvenile fibroadenomas have been reported in the literature along with our case. Patients with giant juvenile fibroadenoma presented at a mean age of 13.92 years and usually after menarche. Juvenile fibroadenomas are usually unilateral, occurring either in the right or the left breast; the majority of them are diagnosed when they are already more than 10 cm in size, and they are most frequently treated with total lump excision. Differential diagnosis includes phyllodes tumors and pseudo-angiomatous stromal hyperplasia. Conservative management is feasible, but surgical excision is recommended to patients with suspicious imaging features or when the mass grows rapidly.

Gene expression profiling of giant fibroadenomas of the breast

INTRODUCTION

Fibroadenomas of the breast present as two phenotypic variants. The usual variety is 5 cm or less in diameter and there is another large variant called giant fibroadenoma which is greater than 5 cm in diameter. Despite of its large size, it is not malignant. The aim of our study is to determine whether this large variant is different from the usual fibroadenoma in terms of its biological pathways and biomarkers.

METHODS

mRNA was extracted from 44 fibroadenomas and 36 giant fibroadenomas, and transcriptomic profiling was performed to identify up- and down-regulated genes in the giant fibroadenomas as compared to the fibroadenomas.

RESULTS

A total of 40 genes were significantly up-regulated and 18 genes were significantly down-regulated in the giant fibroadenomas as compared to the fibroadenomas of the breast. The top 5 up-regulated genes were FN1, IL3, CDC6, FGF8 and BMP8A. The top 5 down-regulated genes were TNR, CDKN2A, COL5A1, THBS4 and BMPR1B. The differentially expressed genes (DEGs) were found to be associated with 5 major canonical pathways involved in cell growth (PI3K-AKT, cell cycle regulation, WNT, and RAS signalling) and immune response (JAK-STAT signalling). Further analyses using 3 supervised learning algorithms identified an 8-gene signature (FN1, CDC6, IL23A, CCNA1, MCM4, FLT1, FGF22 and COL5A1) that could distinguish giant fibroadenomas from fibroadenomas with high predictive accuracy.

CONCLUSION

Our findings demonstrated that the giant fibroadenomas are biologically distinct to fibroadenomas of the breast with overexpression of genes involved in the regulation of cell growth and immune response.

Use of Lateral Oncoplasty for Multiquadrant Giant Fibroadenoma: A Novel Approach

Giant fibroadenomas are uncommon benign lesions, defined as fibroadenomas of >5 cm in size and/or weighing more than 500 g. They can distort the shape of the breast and cause asymmetry, so they should be excised. Here, we report two cases of giant fibroadenoma, where wide local excision and reconstruction with lateral oncoplasty were done. Compared to all previous reports of patients with giant fibroadenoma, where the lump was excised either through a submammary incision or by round block technique depending on the location of the tumour, we used the lateral oncoplasty technique in both patients. Lateral oncoplasty is a new reconstructive option to maintain cosmesis and symmetry after the excision of giant fibroadenomas in the outer and central quadrants of the breast. It is a good option for reconstruction in cases where the defect is very large and facilities for conventional flap surgeries are not available.