Rheumatology, Derbyshire Royal Infirmary, Derby and 1 Breast Institute, Nottingham City Hospital, Nottingham, UK
Correspondence to: N. Raj. E-mail: nicholas.raj{at}btinternet.com
SIR, Granulomatous mastitis is a rare chronic inflammatory condition of the breast that can mimic carcinoma [1]. The histological diagnosis is dependent upon exclusion of other granulomatous or infectious diseases. The aetiology is unknown, but an association with parturition and lactation has led to the proposal of a foreign body reaction to extravasated secretions from the lobules. Blunt trauma and hyperprolactinaemia (with intermittent galactorrhoea) have also been implicated [2, 3]. The optimal management is uncertain, with the initial priority being non-operative diagnosis with multiple core biopsies and imaging. Surgery is contraindicated due to poor wound healing, fistula formation and disease recurrence. In cases reported to date the mainstay of treatment is steroids with good long-term response rates observed. However, recurrences have occurred on cessation of steroids and side-effects are well documented. The response to steroids, combined with similarities microscopically with granulomatous thyroiditis and orchitis [4], have led to an autoimmune process being implicated. We describe our experience with three cases, and the use of immunosuppressive therapy.
The three women ranged in age from 31 to 39 yr (mean 35.3), all were parous (13 children) and had breastfed (cessation varying from 42 to 90 months from presentation). Two presented with single painful breast lumps and one with multiple lumps in both breasts, confirmed on ultrasound and mammography. There was no evidence on examination or investigation of generalized granulomatous or vasculitic disease. All underwent an ultrasound guided core biopsy, and in two cases this was repeated for clarification of the diagnosis. The histology was compatible with granulomatous mastitis in all three cases, showing non-caseating granulomatous inflammatory changes centred on the lobules. All cases were negative for microbiological cultures, stains for tuberculosis and serological investigations for other granulomatous and vasculitic diseases. All three patients responded well to 60 mg daily of oral prednisolone, but relapsed on dose reduction. Case A was started on methotrexate, and after 7 months of treatment with 15 mg weekly was able to stop steroids without relapse. Twelve months later she is still controlled on 12.5 mg, but has not been able to reduce this dose. Case B was treated with 8 months of methotrexate at 10 mg weekly, during which time she stopped steroids successfully. She has been off all treatment for 6 months and has had no relapse of granulomatous disease, but suffers with chronic breast pain that was never eased by treatment. During treatment she underwent surgery for a benign pituitary tumour. She is now treated with thyroxine. Case C felt short of breath on methotrexate at 7.5 mg and was changed to azathioprine, although clinically she had no evidence of methotrexate-induced pneumonitis. She has had long-term steroids and her management has been complicated by the development of cushingoid features and mood disturbances attributed to the steroids, and hyperprolactinaemia secondary to paroxetine. Having started immunosuppressive therapy 4 months ago she has clinically improved, and decreased her steroids from 15 mg to 7.5 mg daily.
In conclusion, granulomatous mastitis is a troublesome condition that presents management problems due to side-effects of steroids. Rheumatologists may well be asked to help in the management of these patients. Our experience with the use of methotrexate and azathioprine as steroid-sparing agents in these cases indicates that remission may well be attainable without long-term steroid use. These findings are consistent with a recent series of five patients treated in Australia [5] with methotrexate. Immunosuppressive therapy can be effective in reducing steroid use, controlling the inflammatory process and thus preventing further complications.
The authors have declared no conflicts of interest.
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