Pediatric Dermatology Vol. 28 No. 3 299–301, 2011
Neonatal Rhabdomyosarcoma Misdiagnosed as a Congenital Hemangioma Hala Megarbane, M.D.,* Francois Doz, M.D., Yves Manach, M.D.,à Christopher Fletcher, M.D.,– Francis Jaubert, M.D.,# Yves de Prost, M.D., Ph.D.,* and Dominique Hamel-Teillac, M.D.* *Department of Dermatology, Necker Enfants-Malades Hospital, Paris, France, Department of Pediatric Oncology, Institut Curie, Paris, France, àDepartment of Otorhinolaryngology, Necker Enfants-Malades Hospital, Paris, France, –Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, #Department of Pathology, Necker Enfants-Malades Hospital, Paris, France
Abstract: Highly vascularized malignant soft-tissue tumors can clinically and radiologically mimic deep hemangiomas. We present a case of congenital rhabdomyosarcoma of the neck, which was initially identified as congenital hemangioma.
CASE REPORT A 2½-month-old baby boy was referred for evaluation of a large congenital tumor of the retroauricular region. At birth, the tumor measured 5.6 · 6.3 · 2.8 cm and was considered as a congenital hemangioma after MRI exam (Fig. 1A). When seen by us, the lesion had doubled in size. Clinical examination revealed a firm, nonpulsatile, fleshcolored, subcutaneous mass with a lumpy surface and overlying vessels (Fig. 1B). There was no audible bruit on auscultation. The lesion was painless. Laboratory tests showed normal fibrinogen, normal D-dimers, and normal platelet count. The C-reactive protein was 17 mg ⁄ L. A Doppler-ultrasound of the neck was performed suggesting again the diagnosis of hemangioma. As a result of the large size of the tumor, its rapidly growing rate and diagnostic uncertainty, surgical resection was performed.
Histopathology, immunophenotype, in addition to the normal molecular analyses were in favor of a welldifferentiated embryonal rhabdomyosarcoma classified as stage I of more than 5 cm (T1b,No,Mo; IRS1) (Fig. 2A–C). DISCUSSION Congenital and neonatal rhabdomyosarcomas (RMS) represent less than 5% of all RMS. Clinical appearance may vary widely. Those presenting as a solitary fully formed tumor at birth or as a rapidly growing tumor, particularly on the face and neck, are more likely to be misdiagnosed as vascular tumors (1). Unfortunately, radiologic imaging techniques have shown poor discrimination between highly vascularized malignant soft-tissue lesions and vascular lesions. In our case, the presence of a fully formed tumor at birth virtually eliminates infantile hemangioma from diagnostic
Address correspondence to Hala Me´garbane´, M.D., Division of Dermatology, Saint George Hospital, University Medical Center and Balamand University, Beirut, Lebanon, or e-mail: hala_
[email protected]. DOI: 10.1111/j.1525-1470.2010.01210.x
2010 Wiley Periodicals, Inc.
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Figure 1. (A) Brain MRI showing a well-delineated homogenous soft-tissue mass localized behind the right ear lobe, composed of two compartments separated by a septum. Note the absence of liquid component. (B) Patient’s photographs showing the tumor.
consideration. Congenital hemangiomas are fully formed at birth but do not experience rapid growth thereafter. They are classified as either rapidly involuting or noninvoluting. Other vascular tumors such as tufted angioma and kaposiform hemangioendothelioma may have sudden enlargement but are usually associated with profound coagulopathy and consumptive process (Kasaback–Merritt syndrome). These lesions have a distinctive violaceous color, with an infiltrative nodular growth pattern that closely mimics a malignant tumor (2–4). Other diagnoses to consider for such a large, solitary, congenital, increasing tumor of head or neck include lymphangioma, benign growths (solitary myofibroma and lipoblastoma), and malignant tumors (teratoma and fibrosarcoma). Macrocystic lymphangioma generally involves a swelling or mass that is soft to palpation, well
Figure 2. Histopathology of the tumor showing (A) (HES · 200) spindle cells, with some of them elongated pink cytoplasm suggestive of striated muscle differentiation but no cambial layer at the junction with epidermis, (B) (Des · 200) desmine immunostaining of the same elongated cells confirming striated muscle differentiation; the other interstitial spindle cells remains negative and myogenin is negative, and (C) (Act · 200) strongly positive smooth muscle actin on the remaining small interstitial cells showing a smooth muscle type of differentiation. There is no other type of differentiation demonstrated by immunohistochemistry: S100 is negative.
Megarbane et al: Neonatal Rhabdomyosarcoma
circumscribed or diffuse with defined or ill-defined borders. Most tend to progress with time. Imaging studies are essential to establish the diagnosis by showing the liquid consistency of the lesion (4). Large solitary myofibroma and fast growing lipoblastoma can also mimic vascular tumors. Skin biopsy in the former and imaging studies demonstrating adipose tissue in the latter should be helpful to establish the correct diagnosis (1). Teratomas are most commonly located in the sacrococcygeal region but cases of head and neck teratomas have been reported. This tumor can enlarge rapidly and is characterized by its firmness. Elevation of alpha-feto-proteins and bHCG are helpful in establishing the diagnosis as well as computerized tomography (5). Infantile fibrosarcoma is an indolent, slow-growing, malignant spindle cell tumor that may clinically masquerade as an ulcerated hemangioma. This malignant vascular-appearing tumor does, however, express characteristic cytogenetic and molecular abnormalities (2). CONCLUSION Although soft-tissue tumors of the neonatal period are very rare, pediatric dermatologists must be aware of soft-
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tissue malignancies masquerading as vascular tumors. Imaging studies may not be helpful in distinguishing the two conditions. Ultimately an incisional or excisional biopsy may be required. REFERENCES 1. Frieden IJ, Rogers M, Garzon MC. Conditions masquerading as infantile haemangioma: part 2. Australas J Dermatol 2009;50:153–170. 2. Yan AC, Chamlin SL, Liang MG et al. Congenital infantile fibrosarcoma: a masquerader of ulcerated hemangioma. Pediatr Dermatol 2006;23:330–334. 3. Walker Metry D, Hebert AA. Benign cutaneous vascular tumors of infancy: when to worry, what to do. Arch Dermatol 2000;136:905–914. 4. Wassef M, Vanwijck R, Clapuyt P. et al. Vascular tumours and malformations, classification, pathology and imaging. Ann Chir Plast Esthet 2006;51:263–281. 5. Halperin EC. Neonatal Neoplasms. Int J Radiat Oncol Biol Phys 2000;47:171–178.
