Giant pilomatricoma and psoriasis vulgaris with myotonic dystrophy

ARTICLE

Auteur(s) : Kozo Nakai, Kozo Yoneda, Reiko Maeda, Ikumi Yokoi, Natsuko Fujita, Asuka Munehiro, Tetsuya Moriue, Yasuo Kubota

Department of Dermatology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, Japan 761-0793

The prevalence of multiple pilomatricomas (MPs) in patients with myotonic dystrophy (MyD) is greater when compared to that of the general population [1]. We report a giant perforating pilomatricoma and psoriasis vulgaris developing in a patient with MPs associated with MyD.

A 45-year-old Japanese male who was diagnosed 30 years earlier with MyD and MPs, sought treatment for a large mass on his head. Three MPs had previously been excised and diagnosed as pilomatricoma. He reported first noticing the presence of the large mass a few years before. He noted that he had erythema with scales on his face and head approximately 4 years earlier, and the area of erythema had been spreading. Since then, the mass had progressively increased in size with a recent acceleration and ulceration during the last 2 months. Physical examination revealed myotonic facies with facial weakness, ptosis and alopecia (figure 1A). The mass on his left posterior head was a 5- × 4- × 2-cm, non-tender, firm, fixed ulcerated tumor (figure 1B). More than ten small nodules (about 1 cm) were observed on his head and arms. Clinical differential diagnoses of the large mass included squamous cell carcinoma. MRI examination of the head showed a large, well-defined nodule with abundant calcifications but no bone involvement. Histopathological examination of a biopsy specimen revealed circumscribed neoplasms within the dermis, composed of islands of basophilic cells and ghost cells, consistent with the diagnosis of pilomatricoma (figure 1C). No malignant features, including mitoses and necroses, were observed. Subsequently, complete surgical excision of the skin nodule was performed. We observed erythema with scale around the mass (figure 1B), and on his elbows and knees. No nail lesions and no arthritis were observed. The erythema lesion and scale were clinically diagnosed as psoriasis vulgaris and responded well to topical corticosteroid ointment. He had no family history of psoriasis vulgaris.

MyD type 1, also known as Steinert disease, is the most common form of adult onset muscular dystrophy. It is characterized by alteration in the skeletal muscle, lens, heart, skin, bone, and central and peripheral nervous systems. The clinical manifestations are highly variable. Steinert disease is caused by a mutation in the dystrophia myotonica protein kinase (DMPK) gene on chromosome 19q13.3. The functional role of DMPK has not yet been fully understood, although it is suggested to play an important role in calcium homeostasis and signal transduction [2]. The derangement of calcium homeostasis and signal transduction influences the differentiation of epidermal cells. Therefore, the higher frequency of PMs in Steinert disease may result from the role of DMPK. In our patient, psoriasis vulgaris developed just before a pilomatricoma progressively increased in size and ulcerated. Interestingly, the derangement of calcium homeostasis and signal transduction in psoriasis vulgaris has also been suggested. In addition, the mutation in a gene localized at 19q13.3 affects the expression of neuropsin which is highly expressed in psoriatic epidermis [3]. Another possible mechanism involves the increased levels of β-catenin which has been reported in both pilomatricoma [4] and psoriasis vulgaris [5]. However, the reason why the rapid development of both skin lesions occurred in our patient may require further research and reports.

Acknowledgements

References

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3 Kuwae K, Matsumoto-Miyai K, Yoshida S, et al. Epidermal expression of serine protease, neuropsin (KLK8) in normal and pathological skin samples. Mol Pathol 2002; 55: 235-41.

4 Moreno-Bueno G, Gamallo C, Perez-Gallego L, et al. beta-catenin expression in pilomatrixomas. Relationship with beta-catenin gene mutations and comparison with beta-catenin expression in normal hair follicles. Br J Dermatol 2001; 145: 576-81.

5 Hampton PJ, Ross OK, Reynolds NJ. Increased nuclear beta-catenin in suprabasal involved psoriatic epidermis. Br J Dermatol 2007; 157: 1168-77.