SCIENTIFIC ARTICLE
Superficial Angiomyxoma of the Thumb Mimicking a Malignant Bone Tumor: Case Report Anil K. Bhat, MS, Ashwath M. Acharya, MS, Prashant Rosario, MBBS, C. K. Anuradha, MD, Lakshmi Rao, MD
Superficial angiomyxoma is a distinctive cutaneous soft tissue neoplasm commonly involving dermal and subcutaneous tissues and showing a prominent angiomyxoid matrix interspersed with numerous blood vessels. We report a case of superficial angiomyxoma in a 70-year-old man who presented with a fungating swelling on the distal phalanx of the thumb mimicking a malignant tumor. The diagnosis of superficial angiomyxoma was made based on histopathology and immunohistochemistry. We report this lesion because of its rare presentation with extensive distal phalangeal osteolysis mimicking a malignant bone tumor. (J Hand Surg Am. 2014;39(5):937e939. Copyright Ó 2014 by the American Society for Surgery of the Hand. All rights reserved.) Key words Thumb tumor, angiomyxoma, lytic lesion.
S
described in 1988 by Allen et al.1,2 It is still a poorly recognized cutaneous tumor.2 It is a dermal and subcutaneous benign tumor characterized by extensive myxoid stroma and prominent small blood vessels.2 The lesion is generally poorly circumscribed and nodular with a predilection for the trunk, lower extremities, head, neck, and genital region.3 It has a propensity for local recurrence, but metastasis has not been reported.1 Subungual and digital tumors without skeletal involvement have been reported.4 Manasori et al5 described a superficial angiomyxoma of the thumb with osteolysis of the distal phalanx well separated from the bone under the nail. This case report describes a similar condition, but with extensive destruction of the distal phalanx of the thumb, an unusual presentation of a hamartoma, which if treated early gives good results.5 UPERFICIAL ANGIOMYXOMA WAS
From the Hand and Microsurgery Unit, Department of Orthopaedics; and the Department of Pathology, Kasturba Medical College Hospital, Manipal University, Manipal, India. Received for publication July 30, 2013; accepted in revised form January 14, 2014. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Ashwath M. Acharya, MS, Division of Hand and Microsurgery, Department of Orthopaedics, Kasturba Medical College, Manipal University, Manipal 576104, India; e-mail:
[email protected]. 0363-5023/14/3905-0015$36.00/0 http://dx.doi.org/10.1016/j.jhsa.2014.01.004
CASE REPORT A 70-year-old man presented with a 1-year history of a slow-growing mass on the right thumb. The swelling was insidious in onset, painless, and progressive. Eight days before consultation, the mass had broken through the skin and bled intermittently. Examination revealed a globoid swelling with a fungating 2.5 1.5-cm mass involving the entire nailbed (Fig. 1). A provisional diagnosis of a malignant neoplasm was made. Radiographs revealed extensive destruction of the distal phalanx of the thumb (Fig. 2). The erythrocyte sedimentation rate was 36. Chest radiograph, hemogram, serum electrolytes, and liver and kidney function tests were normal. Chest computed tomographic scan and bone scan were not done. In view of the fungating nature of the lesion and extensive destruction of the terminal phalanx that was not salvageable, amputation at the interphalangeal joint was performed. The patient was not willing to have an incisional biopsy or any secondary procedures owing to cost constraints. Gross examination of the specimen revealed a glistening white, soft mass infiltrating the distal phalanx. Histopathological examination revealed a diffuse dermal and subcutaneous nodular myxoid lesion with predominant hypocellular areas and few hypercellular areas. Spindle and stellate cells were seen with benign cellular morphology in an extensively myxoid stroma with arborizing thin-walled vessels, focal microcysts, sparse lymphocytic infiltrate, and mast cells (Fig. 3). The
Ó 2014 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
937
938
SUPERFICIAL ANGIOMYXOMA OF THUMB
FIGURE 1: A Dorsal view and B lateral view showing the fungating mass involving the terminal phalanx of the right thumb.
fibrokeratoma, focal cutaneous mucinosis, digital mucous cyst, pyogenic granuloma, osteomyelitis, or the Carney complex.2,5 Considering the size and type of the lesion, these conditions could be ruled out in our patient. Pyogenic granuloma usually does not affect the bone. Osteomyelitis is unlikely to result in such a fungating mass. Malignancy of bone was our original diagnosis. Radiography and magnetic resonance imaging revealed spoon-like osteolysis, homogeneously high signal intensity on T2, and low signal intensity on T1-weighted images, indicative of a cartilaginous matrix.5 In our patient, extensive destruction on radiographs suggested either an aggressive soft tissue or bone malignancy such as eosinophilic granuloma, epithelioid cyst, giant cell tumor, chondrosarcoma, or metastasis.5,8,9 Histopathologically, this tumor resembles a few malignant myxoid soft tissue tumors.3 The differential diagnosis for malignant tumors includes myxofibrosarcoma and myxoid liposarcoma. Taking into consideration the histopathological features in the background of strong CD34 and sparse S100 positivity, we made a preliminary diagnosis of superficial angiomyxoma. In early presentations, marginal excision can be done, but the patients are counseled about local recurrence, which is as high as 30% to 40%.1,2,5 Distant metastasis has not been described with this tumor.1,2,5 There are at least 3 previous reports on digital superficial
tumor cells were CD34 positive, which indicated the fibroblastic nature of the tumor. The cells were sparsely positive for S100, which is rarely seen in superficial angiomyxoma. The S100 is strongly positive in neuroid tumors such as neurothekeoma, which is an important differential diagnosis for this condition.6 The CD34 positivity and S100 negativity are usually diagnostic of superficial angiomyxoma.3,6 Features suggestive of primary malignancy of bone or metastasis were absent. We made a diagnosis of superficial angiomyxoma. The patient subsequently went back to his previous level of activity as a farmer, with no evidence of recurrence at 1-year follow-up. Hand and chest x-rays and blood tests were normal at that time. DISCUSSION Superficial angiomyxoma, also known as cutaneous myxoma, was described by Allen et al1 and was more specifically defined by Calonje et al.2 Superficial angiomyxoma affects adults and is more common in males.1,2,7 These lesions can arise from anywhere in the superficial tissues, but mostly have a predilection for head and neck, trunk, lower limbs, and genitalia.1e7 Most cases present as cutaneous papules, nodules, or polypoid lesions.2 They are rarely in the extremities.2 Clinically, the tumor can mimic other digital cutaneous lesions such as cutaneous myxoid cyst or J Hand Surg Am.
r
Vol. 39, May 2014
SUPERFICIAL ANGIOMYXOMA OF THUMB
939
FIGURE 2: Radiographs showing involvement of the terminal phalanx. A Oblique view. B Posteroanterior view.
Editor note: Please see the letter to the editor in this issue describing a similar case.
REFERENCES 1. Allen PW, Dymock RB, MacCormac LB. Superficial angiomyxoma with and without epithelial components: report of 30 tumors in 28 patients. Am J Surg Pathol. 1988;12(7):519e530. 2. Calonje E, Guerin D, McCormick D, Fletcher CD. Superficial angiomyxoma: clinicopathologic analysis of a series of distinctive but poorly recognized cutaneous tumors with tendency for recurrence. Am J Surg Pathol. 1999;23(8):910e917. 3. Weiss SW, Goldblum JR. Benign soft tissue tumors and pseudotumors of uncertain type. In: Weiss SW, Goldblum JR (eds). Enzinger & Weiss’s Soft Tissue Tumors. 5th ed. Philadelphia: Mosby Elsevier Inc.; 2008:1076e1080. 4. Misago N, Mori T, Yoshioka M, Narisawa Y. Digital superficial angiomyxoma. Clin Exp Dermatol. 2007;32(5):536e538. 5. Manasori I, Kojima K, Yamahira K, et al. Superficial angiomyxoma of the thumb: report of a rare case and review of literature. Eur J Radiol Extra. 2010;73(1):e29e32. 6. Beer TW, Lam MH, Heenan PJ, et al. Tumors of fibrous tissue involving the skin. In: Elder DE, Elenitsas R, Johnson BL Jr, Murphy GF, Xu X (eds). Lever’s Histopathology of the Skin. 10th ed. Philadelphia: Lippincott Williams & Wilkins; 2008:997. 7. Yamamoto K, Kondo A, Iwashita K, et al. A case of superficial angiomyxoma. Tokai J Clin Med. 2006;31(2):43e45. 8. Ahlmann ER, Greene NW, Menendez LR, Stevanovic MV. Unusual locations for metastatic malignancy of the hand: a report of three cases. J Surg Orthop Adv. 2008;17(4):267e270. 9. Kiatisevi P, Thanakit V, Boonthathip M, Sukanthanak B, Witoonchart K. Giant cell tumor of the distal phalanx of the biphalangeal fifth toe: a case report and review of the literature. J Foot Ankle Surg. 2011;50(5):598e602. 10. Perret AG, Perrot JL, Dutiot M, et al. Superficial angiomyxoma: report of four cases including two subungual tumors. Am Pathol. 2005;25(1):54e57.
FIGURE 3: Hypercellular myxoid areas with spindle (thin arrow) and stellate (thick arrow) cells (hematoxylin-eosin stain; magnification 40).
angiomyxoma. One involved the thumb extending to the distal phalanx, which was treated by excision.5 Another case report described a flesh-colored nodule affecting the index finger proximal interphalangeal joint. The third report mentioned 2 subungual lesions involving the thumb and the fifth toe.10 None of these reports noted fungating masses or recurrences. Our histological and radiological findings consolidate the observation that superficial angiomyxomas need not be cutaneous alone. Wide excision should be considered in the presence of extensive soft tissue involvement. J Hand Surg Am.
r
Vol. 39, May 2014