INTRODUCCIÓN

Pseudoangiomatous stromal hyperplasia, commonly known as PASH, is a rare benign disease and its etiology is currently unknown¹. It was first described in 1986 by Vuitch et al², and appears frequently between the ages of 12 to 75 years³. It presents as a large, solitary, firm, painless, circumscribed, delimited and mobile nodular mass of variable size between 2 and 13 cm. Frequently unilateral, there are reports of bilaterality⁴. In some cases, it is diagnosed in the biopsy. PASH can also arise in the axillary tail of the breast and very rarely involves the nipple-areola complex and the axillary accessory breast tissue¹. The most important differential diagnosis is with angiosarcoma⁵.

Excisional biopsy is the treatment and the final diagnosis is histologic⁶. Diagnosis, management and esthetic outcome are very important in this age group. These large tumors are deforming and require early surveillance, diagnosis and management in order to avoid radical surgeries that cause large scars, deformity and asymmetry, and may have repercussions on the behavior and emotional state of the adolescent.

Among the most common benign breast tumors in adolescence are juvenile fibroadenoma, juvenile hypertrophy (virginal) and pseudoangiomatous stromal hyperplasia. Phyllodes tumors, lymphomas, angiosarcomas are extremely rare^7-10).

We present the case of a patient who underwent a submammary approach that preserved breast symmetry and esthetics.

PRESENTATION OF THE CLINICAL CASE

An adolescent girl aged 14 years and 3 months reported that she noticed a progressive increase in the size of her right breast over 6 months, with asymmetry of the breasts and no pain. Her 42-year-old mother was a housewife and her 43-year-old father was a businessman, both apparently healthy. The teenager was born with a normal delivery, weighing 3,200 g, had complete vaccinations, menarche at 11 years of age, catamenial regimen 4/30, without dysmenorrhea.

At the admission examination she weighed 53 kg, height 1.54 m, body mass index 22.3, cooperative during the evaluation. General, nutritional and hydration status was regular. The right breast, Tanner stage 4, was occupied by a single mass with defined borders of 9 x 6 cm in radius 6 to radius 12, mobile, non-painful, of hard consistency and deforming the nipple and areola. The left breast, Tanner stage 4, showed no alterations. Biochemistry, hematological and urine tests were normal. Right breast ultrasound showed a circumscribed oval mass with acoustic shadow, measuring 9 x 6 cm in radius 11 and 12 (Figure 1).

Figure 1 (a, b). in the breast ultrasound before surgery, the findings are variable, but in most cases a solid, circumscribed, oval or rounded mass is observed, as in the case presented. 

Surgical treatment consisted of excision of the tumor (Figure 2) through a submammary approach (Figure 3). No complications were evidenced during the postoperative period, and she was discharged after 1 day of hospitalization, with analgesics, antibiotics and breast bandage. She went to the control 72 hours after de postoperative period for removal of the bandage. After one week the sutures were removed. On physical examination, the operative wound was closed and without phlogosis.

Figure 2 Operative specimen: a solid mass with defined borders, grayish brown, 11 x 7.7 x 5.5 cm, is observed. 

Figure 3 a. right submammary incision. b. control at one week. 

The histological report was: Grayish-brown tumor of 11 x 7.7 x 5.5 cm in size. Final diagnosis:

Pseudoangiomatous stromal hyperplasia (PASH) (Figure 4). Currently, the patient continues to be monitored and with favorable follow-up. In the last control in 2021, there was no evidence of another tumor growth.

Figure 4 histological description: (a) histological study confirms pseudoangiomatous stromal hyperplasia: histological sections show mammary parenchyma with numerous stromal clefts. these clefts are lined by myofibroblasts. the spaces produced by the clefts are empty, simulating complex anastomosed blood vessels. (b) clefts surround lobules of normal appearance and involve both the interlobular and the intralobular stroma. 

DISCUSSION

We report the first case of PASH in our institution, being important to make known this pathology, frequent between the ages of 12 to 75 years and more prevalent in women of reproductive age. In adolescence, they are usually benign. The etiology of PASH is unknown.

A complete medical history, general physical examination and breast examination should be performed in any gynecologic check-up of an adolescent girl. In these cases, the patient will come for consultation with a well-demarcated, hard, non-painful, deforming and rapidly growing lump.

The differential diagnosis of breast tumors is fundamental for management of fibroadenomas, gigantojuvenile fibroadenomas, phyllodes tumor, lymphoma. Among the diagnostic tests, breast ultrasound^11-13,16 in this type of tumor is non-specific, generally finding a solid, circumscribed, oval or round mass. The diagnosis is anatomopathological; a breast parenchyma with numerous stromal clefts is described. These clefts are lined by myofibroblasts¹⁵. The spaces produced by the clefts are empty, simulating complex anastomosed blood vessels. The clefts are present in both the interlobular and intralobular stroma.

In this age group, the surgical approach should be conservative and adequate. Patients should be followed up, because recurrence occurs in around 15 and 22% of cases^8,14,16.

In conclusion, pseudoangiomatous stromal hyperplasia is a lesion that is generally seen in women of reproductive age or as an incidental finding as a result of a biopsy. However, it has also been described in girls and adolescents as a palpable, unilateral, firm, non-painful, mobile mass. Diagnosis is by imaging and histology. Differential diagnosis with gigantojuvenile fibroadenomas and lymphomas is essential. Surgical treatment should be conservative in this age group.