2 The procedure
2.1.1 A fibroadenoma is a benign solid lump of breast tissue, which is thought to result from an increased sensitivity to oestrogen. Fibroadenomas are very common and it is not unusual to have more than one. They are mostly found in young women but can occur in women of any age.
2.1.2 Most fibroadenomas do not enlarge after diagnosis. Some get smaller and some eventually disappear over time. These recommendations relate to options for breast fibroadenomas that do not resolve.
2.1.3 Once the diagnosis has been confirmed, conservative management is often agreed, with clinical review only. If the fibroadenoma persists or grows, or if the patient is anxious for it to be removed, it can be excised by a small open operation using general anaesthesia. Interstitial laser therapy is an alternative to open surgery.
2.2.1 High-energy light delivered via a laser fibre is used to destroy the fibroadenoma. The fibre is positioned through a needle inserted percutaneously under local anaesthesia. The tip of the needle is positioned at the centre of the lump under ultrasound guidance. Laser energy is delivered through a pre-sterilised bare fibre passed through the needle a short distance beyond the tip. The energy is delivered in continuous wave mode for a few minutes. For larger lumps, multiple needles are inserted 1 cm apart, with a laser fibre through each.
2.2.2 There may be lower rates of infection with interstitial laser therapy compared with open surgery, and a more acceptable aesthetic result.
2.3.1 In a case series of 24 patients, interstitial laser therapy reduced fibroadenoma size (as assessed by ultrasound measurement) from a mean length of 25 mm at baseline to 14 mm at 3 months, 10 mm at 6 months, and 0 mm at 12 months. There were no palpable fibroadenomas in the 14 women followed-up for 12 months.
2.3.2 In another case series, the mean volume of the fibroadenomas in 27 women was significantly smaller 8 weeks after the procedure (0.68 cm3 compared with 2.17 cm3 at baseline; p < 0.001). Clinical assessment also demonstrated a significant decrease in area following interstitial laser therapy (a mean of 1.25 cm2 compared with 2.60 cm2 at baseline; p < 0.001). However, at 8 weeks 37% (10/27) of women had a residual lump with a diameter of more than 1 cm. For more details, refer to the Sources of evidence.
2.3.3 The Specialist Advisors noted that the lack of material for biopsy with this procedure (in contrast to surgical excision) means that the benign diagnosis cannot be confirmed.
2.4.1 In a case series of 24 women who had undergone interstitial laser therapy, 83% (20/24) reported some discomfort during the procedure. Severe pain in 17% (4/24) of women led to the treatment being stopped prematurely. In this case series and another that involved 27 women, local tenderness that lasted from 1 to 8 weeks was reported in all of the women.
2.4.2 In one of the case series, 30% (8/27) of women had skin blanching at the needle site after 80–100 seconds of the treatment, and these women later developed epithelial breakdown and hyperpigmentation in the same area (follow-up 8 weeks). In the second case series, 17% (4/24) of women had bruising that resolved within 1 week. For more details, refer to the Sources of evidence.
2.4.3 The Specialist Advisors noted that the reported adverse events include local burns at the needle site, and that the theoretical complications include local infection, and bleeding if the needle strikes a blood vessel.