Abstract
Juvenile fibroadenoma is the most common breast mass in adolescents accounting for 0.5–4% of all cases of fibroadenomas. Giant fibroadenomas are well-circumscribed, firm breast masses characterized by proliferation of epithelial and connective tissue. They are defined as being larger than 5 cm or weighing more than 500 g. The peak age has been reported between the ages of 17 and 20, with less than 5% of these in patients less than 18-years-old.
We present a 9-year-old, pre-menstrual, Nigerian female with no known family history of breast masses or cancers who developed spontaneous giant fibroadenoma measuring approximately 13
Introduction
Juvenile fibroadenoma is a rare disorder accounting for 0.5–4% of all cases of fibroadenomas [1]. It is described by a well-circumscribed, firm and rubber-like breast mass characterized by proliferation of epithelial and connective tissue to varying proportions. They are characterized as a giant fibroadenoma when they are larger than 5 cm or weigh more than 500 g [2,3]. The peak age has been reported between the ages of 17 and 20, with less than 5% of these in patients less than 18-years-old [4]. They have been more frequently reported in black patients [1]. These masses can grow exceedingly large, causing skin ulceration and vascular congestion [2,5,6].
The differential diagnosis for a rapidly enlarging breast mass in an adolescent includes giant fibroadenoma, cystosarcoma phyllodes, and virginal hypertrophy [3]. These etiologies are thought to be a part of a continuum of the same disease process [7]. Fibroadenoma may be followed without further investigation if it is not symptomatic. Alternatively it can be treated successfully with enucleation. In contrast, phyllodes tumor requires treatment with wide local excision or mastectomy, as there are risks of recurrence and metastasis. There have even been reports of benign and borderline phyllodes metastasizing [11]. Breast cancer in children is rare, however it has been reported and is also part of the differential diagnosis [2,8]. This risk of malignant degeneration of a fibroadenoma is less than 0.3% [6]. Breast cancer concomitant with juvenile fibroadenoma has also been observed [9,10]. A study by Vidal et al. investigated the genetic signature of different fibroepithelial lesions, and found that fibroadenomas and benign phyllodes tumors are undistinguishable from normal breast tissue. In contrast, malignant phyllodes tumors had similar genetic profiles to breast carcinomas [11]. A family history of breast cancer has been linked in 26–58% of patients with juvenile fibroadenoma [10,12]. Some patients have developed breast cancer in eight to nine years after the diagnosis and treatment of juvenile fibroadenoma [12].
Case report
A 9-year-old, pre-menstrual, Nigerian girl presented with a one month history of rapidly growing right breast. Breast development began when she was eight-and-a-half years old with the right breast always being larger than the left. Over the course of one month, the right breast had continued growing, becoming hard and warm. She was taken to the emergency department where she was treated for an infection. After completing a course of antibiotics, her right breast continued to increase in size. The patient did not have a family history of breast cancer, breast masses, or other cancers. On physical exam, the right breast was considerably larger than the left with a palpable, firm round mass that was tender to touch, measuring approximately 13 cm × 13 cm (Fig. 1). Ultrasound revealed a large, echogenic, solid mass with subtle vascularity and no calcifications. The mass was measured to be 11.2
Discussion
While breast masses in young patients are uncommon, giant fibroadenomas are the most frequent cause of unilateral breast enlargement in adolescent females [1]. The precise cause of these large masses is still unknown. Reproductive hormones may play a role since such lesions occur more frequently in puberty, pregnancy, and while taking oral contraceptives [13]. A case of giant fibroadenoma in a 12 year old female resulting from trauma has been previously reported [14]. Although they are benign neoplasms, giant fibroadenomas can compress surrounding tissue and alter lobule structure due to their increased size and vascularity [15]. Additionally, complex fibroadenomas containing histological changes such as macrocysts, calcifications, aprocrine changes, and sclerosing adenosis may increase the risk for developing breast cancer [16]. Superficial manifestations of giant fibroadenomas can be similar to that of malignant processes, such as ulceration, skin dimpling, and nipple inversion [15]. Because of these complications and potential risks, emphasis should be placed on early detection, diagnosis, and treatment of juvenile fibroadenomas.
Diagnosis of juvenile fibroadenomas originates with detection by either the patient or provider along with a detailed history and physical examination with chief complaints of new, painful, or increasing size breast masses. The most definitive primary diagnostic studies for fibroadenoma are breast ultrasound, and either core biopsy or fine needle aspiration [17]. Ultrasound is preferred over other imaging modalities such as mammography, computed tomography, and magnetic resonance imaging due to concerns of excessive radiation exposure to young patients. Furthermore, ultrasound studies identify masses in fibroglandular breasts, such as those of adolescent females, better than in fatty breasts [18,19].
Core biopsy was not performed in the present case as surgical resection was determined to be the optimal course of treatment upon diagnosis, thus removing the need for an additional invasive procedure. Tissue diagnosis by excision is preferred over percutaneous biopsy in giant fibroadenomas since the latter does not address mass effects and does not diagnose many of these cases [15,20]. Intraoperative pathology findings of the mass and capsule confirmed the initial diagnosis of fibroadenoma.
Although such cases typically occur in late adolescence, we describe a 9 year-old patient with no known family history of breast masses or cancers who developed spontaneous giant fibroadenoma. Because of the patient’s young age and potential for further breast development, special surgical consideration is placed on cosmesis, maintaining lactation ability, and preservation of breast parenchyma [16,21]. The patient and her mother were counseled on possible plastic surgery in the future to obtain breast symmetry. However, such intervention may not be needed since further development of the operated breast is likely given the patient’s age. The patient will need to be vigilant and closely followed for future breast masses or abnormalities that may form as she progresses through adolescence and adulthood.
Conclusion
Presentations of enlarging breast masses in pediatric patients should have fibroadenoma considered as a differential diagnosis, with confirmation by ultrasound and histological analysis. The case reported suggests that rapid growth of a breast mass can be of great concern to young patients whose breasts are in the early formative stages. Therefore, the importance to promptly rule out malignant processes or phyllodes tumor, and educate young patients and their families on treatment options that fit their unique concerns and circumstances is highlighted.