Keloids associated with mammography: A rare but possibly neglected phenomenon

Dear Editor, Mammography has been a widely used first-line screening tool for breast cancers but is criticized for pain experience and discomfort during examination, contributing to non-re-attendance.[1] In addition to pain, adverse consequences from mammography include radiation exposure, false-positive biopsies, and unnecessary anxiety.[1] We present a case of linear rashes developing on the breasts following mammography, which has been rarely reported in the published literature and may be potentially underestimated. A 47-year-old woman with a personal history of keloids presented with multiple erythematous stripes symmetrically distributed on her breasts for 2 years. Physical examination showed numerous firm, erythematous-to-purpuric papules, and symmetric linear plaques on the breasts [Figure 1]. She complained of extreme pain while going through her first mammogram in 2020 with bruising notified in the following days after examination. The asymptomatic linear maculopatches developed on her breasts gradually 1 month after the mammogram, which had been left untreated. However, these striae became progressively larger, infiltrated, and pruritic between 2020 and 2022. There was neither a history of striae gravidarum during her previous pregnancy 15 years ago nor cushingoid features in physical examination.Figure 1: Eruption of linear keloids following mammography. (a) Multiple erythematous-violaceous papules and linear infiltrative plaques symmetrically distributed on the breasts, (b) Lateral view of the stripes on the right breast.We performed a skin biopsy and histological examination showed diffuse dermal fibrosis with sclerotic collagen bundles haphazardly transecting the dermis [Figure 2a and b]. There were no epidermal changes, interface changes, lichenoid infiltrates, granulomas, or dermal mucin deposition in the histopathology [Figure 2a and b]. Immunohistochemical analysis using the Masson's trichrome stain emphasized the dense keloidal collagen bundles, while a-smooth muscle actin staining revealed the presence of myofibroblasts [Figure 2c and d]. An absence of additional chest traumas, breast implantation, body weight changes, or chronic exogenous corticosteroid use was assured by the patient. The keloids secondary to blunt squeezing trauma of mammography were diagnosed. The mammogram revealed no remarkable findings but the patient refused mammography anymore due to experience of pain and keloid formation. The keloids were being treated with intralesional corticosteroid injection every 2 weeks and gradually shrank after 2 months.Figure 2: Histopathological examination and immunohistochemistry of the skin lesion on the left breast. (a) A well-demarcated dermal nodule composed of closely packed interlacing bundles of spindle cells with a fascicular pattern and sclerotic collagen bands (H and E, ×40), (b) Coarse collagen bundles transecting the dermis in a haphazard fashion (H and E, ×200), (c) Masson's trichrome stain, (d) α-smooth muscle actin stain (monoclonal antibody 1A4).Keloid is an overgrowth of scar tissues extending beyond the previous cutaneous insult, usually following trauma, infection, burn, or inflammation.[2,3] Breast tissues are needed to be compressed between a rigid compression paddle and a support table to flatten the tissues with homogeneous thickness during mammography, resulting in tissue damage with subsequent keloid development.[4] Although keloids may develop spontaneously extremely rarely, most are in fact associated with genetic disorders, certain medical diseases (atopic dermatitis), or medications (letrozole and isotretinoin).[4] Some reports claiming no trauma may be doubtful due to frequent unawareness of minor trauma by the patients.[5] Striae distensae secondary to pregnancy (striae gravidarum) and augmentation mammoplasty, although more common, were less likely for this patient due to neither compatible clinical history nor growth with the clinical appearance and histopathology of atrophic scars as maturing.[6] Carcinoma en cuirasse, carcinoma erysipeloides, granulomatous mastitis, sarcoidosis, breast tuberculosis, and other sclerosing/granulomatous diseases of the breast are other differential diagnoses in the present case. In conclusion, this report highlights the rare presentation of linear keloids resulting from the blunt trauma of mammography. Patients with a predisposition for keloid formation and experiencing extreme pain during mammography with subsequent bruising should be informed of the potential risk of keloid formation despite being rare. Early treatment of visible scars is suggested to prevent the growing of keloids.[7] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent form. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Data availability statement All data generated or analyzed during this study are included in this published article. Financial support and sponsorship Nil. Conflicts of interest Dr. Wei-Ti Chen, an editorial board member at Dermatologica Sinica, had no role in the peer review process of or decision to publish this article. The other authors declared no conflicts of interest in writing this paper.