I ,,m i Myxoma of the skin of a finger Tamara L. Hill,* Billy E. Jones, MD, a and Kim H. Park, MD b Greenville, North Carolina A case of a true myxoma of the fingertip is presented. The lesion was removed by simple shave excision. Reports of myxoma of the skin are r~viewed, and the differential diagnosis of this rare tumor is discussed. (J AM ACAD DERMATOL 1990;22:343-5.) True myxomas are uncommon lesions character- ized histologically by stellate and spindle ceils em- bedded in a feathery matrix rich in mucopolysac- charides and delicate reticulin, l They may occur at many body sites and may be confused with a num- ber of benign and malignant neoplasms as well as with other conditions in which mucinous degenera- tion has occurred. 2 We report a case of an isolated myxoma on a fingertip that most likely originated in the dermis. It showed no evidence of recurrence 6 weeks after shave excision. CASE REPORT A 51-year-old white woman was referred to the East Carolina University School of Medicine Dermatology Clinic for a slowIy enlarging lesion on the tip of the left index finger. Approximately 2 years previously she had first noticed a tiny, flesh-colored papule that she thought was a wart. The lesion grew slowly and did not respond to wart removal treatment. She denied any significant trauma to the finger and had no similar lesions elsewhere. The finger would throb intermittently, especially after minor trauma. On physical examination a flesh-colored, smooth- surfaced, somewhat translucent, 2 • 0.5 cm nodule was present on the radial side of the left index finger (Fig. 1). It was well circumscribed and slightly firm. A shave ex- cision revealed an avascular, glistening, mucinous surface with intricate septae. Histologic examination showed normal epidermis with mild hyperkeratosis. The dermis was expanded by abundant connective tissue mucin that contained benign-appearing, spindle-shaped cells (Fig. From the Section of Dermatology a and Department of Pathology, b East Carolina School of Medicine. Reprint requests: Billy E. Jones, MD, Department of Medicine, East Carolina University School of Medicine, Oreenville, NC 27858- 4354. *Senior medical student, East Carolina University School of Medicine. 16/4/12516 Fig. 1. Flesh-colored lesion on tip of left index finger. 2). There was no increased mitotic activity or evidence of chondroblastic, lipoblastic, or rhabdomyoblastie differ- entiation. A reticulin stain showed a delicate network of fibers throughout the lesion. The derma/ ground sub- stance stained positive with alcian blue at pH 2.5. There was scant vascularity, and the vessels showed mild perivascular chronic inflammation. Radiologic studies of the finger showed only degener- ative arthritic changes at the distal joint. No periosteaI changes were present. Follow-up at 6 weeks showed a well-healed normal distal digit with no evidence of tumor or scarring. DISCUSSION Virehow was the first to use the term myxoma to describe certain tumors that were grossly and mi- croscopically analogous to umbilical tissue. 2 Stout 3 343
Transcript
I , , m i
Myxoma of the skin of a finger Tamara L. Hill,* Billy E. Jones, MD, a and Kim H. Park, MD b Greenville, North Carolina
A case of a true myxoma of the fingertip is presented. The lesion was removed by simple shave excision. Reports of myxoma of the skin are r~viewed, and the differential diagnosis of this rare tumor is discussed. (J AM ACAD DERMATOL 1990;22:343-5.)
True myxomas are uncommon lesions character- ized histologically by stellate and spindle ceils em- bedded in a feathery matrix rich in mucopolysac- charides and delicate reticulin, l They may occur at many body sites and may be confused with a num- ber of benign and malignant neoplasms as well as with other conditions in which mucinous degenera- tion has occurred. 2 We report a case of an isolated myxoma on a fingertip that most likely originated in the dermis. It showed no evidence of recurrence 6 weeks after shave excision.
CASE REPORT
A 51-year-old white woman was referred to the East Carolina University School of Medicine Dermatology Clinic for a slowIy enlarging lesion on the tip of the left index finger. Approximately 2 years previously she had first noticed a tiny, flesh-colored papule that she thought was a wart. The lesion grew slowly and did not respond to wart removal treatment. She denied any significant trauma to the finger and had no similar lesions elsewhere. The finger would throb intermittently, especially after minor trauma.
On physical examination a flesh-colored, smooth- surfaced, somewhat translucent, 2 • 0.5 cm nodule was present on the radial side of the left index finger (Fig. 1). It was well circumscribed and slightly firm. A shave ex- cision revealed an avascular, glistening, mucinous surface with intricate septae. Histologic examination showed normal epidermis with mild hyperkeratosis. The dermis was expanded by abundant connective tissue mucin that contained benign-appearing, spindle-shaped cells (Fig.
From the Section of Dermatology a and Department of Pathology, b East Carolina School of Medicine.
Reprint requests: Billy E. Jones, MD, Department of Medicine, East Carolina University School of Medicine, Oreenville, NC 27858- 4354.
*Senior medical student, East Carolina University School of Medicine.
16/4/12516
Fig. 1. Flesh-colored lesion on tip of left index finger.
2). There was no increased mitotic activity or evidence of chondroblastic, lipoblastic, or rhabdomyoblastie differ- entiation. A reticulin stain showed a delicate network of fibers throughout the lesion. The derma/ ground sub- stance stained positive with alcian blue at pH 2.5. There was scant vascularity, and the vessels showed mild perivascular chronic inflammation.
Radiologic studies of the finger showed only degener- ative arthritic changes at the distal joint. No periosteaI changes were present. Follow-up at 6 weeks showed a well-healed normal distal digit with no evidence of tumor or scarring.
DISCUSSION
Virehow was the first to use the term myxoma to describe certain tumors that were grossly and mi- croscopically analogous to umbilical tissue. 2 Stout 3
proposed three criteria for the diagnosis: (1) the tu- mor is composed of stellate or spindle-shaped cells set in a loose matrix of reticulin and collagen fibers; (2) it is poorly vascularized; and (3) there must be no chondroblasts, lipoblasts, rhabdomyoblasts, or recognizable differentiated cellular elements.
The cause of myxomas is still in dispute. Some investigators believe the neoplasm is derived from primitive mesenchymal cells with capabilities for multipotential differentiation. 3-6 Other authors hy- pothesize that the tumor arises from fibroblasts that produce excessive amounts of mucopolysaccharides, which may inhibit the polymerization of normal collagen.7-9 The questionable cause of myxomas has caused some pathologists such as Silverberg l~ to categorize them as "tumors of uncertain histogene- sis."
A review by Ireland et al. 7 of 58 patients with myxomas of soft tissues substantiated an earlier study by Enzinger 8 that reported a low rate of local recurrence with surgical excision. Of the 58 patients reviewed, only two had local recurrences, and follow- up time varied from 1 to 48 years] This was in di- rect contradiction to Stout's 1948 review, 3 which contended that these tumors are prone to frequent recurrences. Myxomas of infancy and childhood have as good a prognosis as those of adulthood, and, aIthough they can occur at any age, they are most often found in older persons, with an average age of approximately 55 years, l, it
Although most myxomas are found in the heart,
muscles of the extremities, and the jaw, they may also appear in soft tissuesJ Myxomas with osseous involvement usually involve the jaw, and few cases of true myxomas of bone other than the jaw have been reported. However, four cases that involved the periosteum of distal phalanges of the toe have been reported, lz Myxomas may occur in the fingertips or in a subungual location. 2
The differential diagnosis of myxomas includes tumors with notable myxoid degeneration such as chondromyxoid fibroma, chondrosarcoma, fibrosar- coma, and chondroma. These can usually be ex- cluded histologically. Other benign entities to be considered are cutaneous focal mucinosis, cutaneous myxoid or mucous cyst, papular mucinosis, localized myxedema, ganglion, and multiple myxoid fibromas of the fingers.
Cutaneous focal mucinosis is a solitary lesion, usually less than 1 cm in diameter, that forms by deposition of mucinous material in the dermis. It can be differentiated histologically from a myxoma by the presence of areas of fibroblast proliferation in which collagen has been partially replaced by myx- omatous matrix.13 The term cutaneous focal rnuci- nosis has also been used to describe asymptomatic elevated cutaneous lesions that are composed of a mucinous material and that occur on the face, trunk, and extremities but not in proximity to the joints of the hands, wrists, or feet. 13
A cutaneous myxoid cyst, although related to a myxoma, is considered to be a separate entity.14 It
Volume 22 Number 2, Part 2 February 1990 Myxoma of fingertip 345
presents as a soft, dome-shaped nodule located in the dermis of the distal dorsal portions of the fingers and toes that usually involves the proximal portion of the nail fold. There is a tendency toward early liquefac- tion and cavity formation in the cyst. 15 Our patient's lesion did not resemble a myxoid cyst clinically, and the lack of cystic changes histologically further re- inforced our clinical impression.
Papular mucinosis should also be considered be- cause this may appear identical to focal cutaneous mucinosis histologically. However, its gross appear- ance as a discrete to confluent, papular eruption dif- ferentiates it from both focal mucinosis and, as in our patient, a true myxoma.13 The clinical appearance of localized myxedema-- that of a thickened plaque-- usually allows easy differentiation from a superficial myxom a. ~ 3
A ganglion is by far the most common and best known of the superficially located myxoid lesions. It occurs as a unilocular or multilocular cystic mass, usually on the dorsal surface of the wrist in young women. 15 A similarity between myxomas and gan- glion cysts in their early stages is often observed; however, a ganglion develops into a true cyst filled with acid mucopolysaceharides, whereas true myx- omas, such as that in our loagtime patient, do not become cystic]
Finally, a single case report describes a father and his son with multiple wartlike lesions on their fingers and palms. On histologic examination these lesions showed changes compatible with vascular fibromas, myxoid fibromas, and, in a few instances, verruca vulgaris. 16
2. Sanusi L Sublingual myxoma. Arch Dermatol 1982; [ 18:612-4.
3. Stout A. Myxoma: the tumor of primitive mesenchyme. Ann Surg 1948;127:706-19.
4. Ferrans V J, Roberts WC. Structural features of cardiac myxomas: histology, histochemistry, and electron micros- copy. Hum Pathol 1973;4:111-44.
5. McAllister HA, Fenogiio JJ.Tumorsofthecardiovascular system. In: Atlas of tumor pathology. 2nd ed. Washington, DC: Armed Forces Institute of Pathology, 1977.
6. Bell DA, Greco MA. Cardiac myxoma with chondroid features: a light and electron microscopic study. Hum Pathol 1981;12:370-4.
7. Ireland DCR, Soule EH, Ivins JC. Myxoma ofs~matic soft tissues: a report of 58 patients, 3 with multiple tumors and fibrous dysplasia of bone. Mayo Clin Proc 1973;48:401-410.
8. Enzinger FM. Intramuscular myxoma: a review and fol- low-up study of 34 cases. Am J Clin Pathol t965;43:104- 13.
9. Westwood RM, Alexander RW, Bennett DE. Giant odon- togenic myxofibroma: report of a case with histochemical and ultrastructural studies and a review of the literature. Oral Surg Oral Med Oral Pathol 1974;37:83-92.
10. Silvcrberg SG, ed. Principles and practice of surgical pathology;vol l. New York: John Wiley & Sons, 1983:232.
11. Dutz W, Stout AP. The myxoma in childhood. Cancer 1961;14:629-35.
12. Hill JA, Victor TA, Dawson W J, et al. Myxoma of the toe. J Bone Joint Surg [Am] 1978;60:128-9.
14. Johnson JE, Graham JH, Helwig EB. Cutaneous myxoid cyst: a clin icopathological and histochemical study. JAMA 1965;191:109-14.
15. Enzinger FM, Weiss SW, eds. Soft tissue tumors. St Lou- is: CV Mosby, 1988:762-78.
16. Coskey R J, Mehregan AH, Lupulescu AP. Multiple vas- cular fibromas and myxoid fibromas of the fingers. J AM ACAD DERMATOL 1980;2:425-31.
CORRECTION
In the article by Sachlko Miyagawa, MD, Toshie Okuchi, MD, Yuko Shiomi, MD, and Kuniki Sakamoto, MD, "Subacute Cutaneous Lupus Erythematosus Le- sions Precipitated by Griseofulvin" (J AM ACAD DERMATOL 1989;21:343-6), page 343, paragraph l, lines 4 to 7 should read, "We report a case in which griseofulvin was associated with eruptions whose clinical and laboratory features were similar to subacute cutaneous lupus erythematosus." The sentence was erroneously published as, "We report a case of systemic lupus erythematosus in which griseofulvin was as- sociated with eruptions with clinical and laboratory features similar to those of sub- acute cutaneous lupus erythematosus."
