 |
|
Orbital Metastasis and Intraocular Invasion of Malignant Mixed Tumor (Carcinosarcoma) of the Parotid Gland in a Child
Arch Ophthalmol. 2004;122:114-118.
Malignant mixed tumor of the salivary glands is a rare neoplasm, and the majority of these tumors arise from the parotid gland.1 Histopathologically, 3 distinct variants of malignant mixed tumors are recognized, the most common being carcinoma arising from a preexisting pleomorphic adenoma.1-2 The second type is the metastasizing mixed tumor, which has benign-appearing epithelial and stromal components.1-2 The true malignant mixed tumor or carcinosarcoma, an exceptionally rare tumor, is the third subtype and is composed of malignant epithelial and malignant mesenchymal elements.2-3
Less than 5% of all salivary gland neoplasms are seen in patients younger than 16 years and 13% of these tumors are solid, of which only 23% are malignant.4 The most common malignant salivary gland tumor in children is mucoepidermoid carcinoma, followed by rhabdomyosarcoma and acinic cell carcinoma.4 We herein describe a highly unusual patient with a carcinosarcoma of the parotid gland that metastasized to ipsilateral orbit and intraocular structures.
Report of a Case
A 10-year-old boy was seen at another institution because of right orbital and preauricular masses that evolved gradually during a period of 6 months (Figure 1). His medical history included trabeculectomy for right congenital glaucoma at the age of 3 years. His records indicate that there was no evidence of an intraocular mass or iris neovascularization.
|
|
|
|
Figure 1. Patient at initial examination, the day after the incisional biopsy was performed.
|
|
|
Visual acuity in the right eye had remained no light perception since then. Magnetic resonance images showed a right anterior orbital and preseptal mass, as well as a large noncystic tumor occupying the right anterior superficial part of the parotid gland (Figure 2). After an unsuccessful trial of systemic antibiotics for 10 days, an incisional biopsy specimen obtained through the superior lid crease was reported as showing alveolar rhabdomyosarcoma. A fine-needle aspiration biopsy specimen from the parotid mass showed round-cell malignant tumor, which was interpreted as metastatic rhabdomyosarcoma.
|
|
|
|
Figure 2. T1-weighted axial magnetic resonance images. A, The anterior orbital mass is homogeneously hypointense relative to the orbital fat. B, A large, homogeneous solid mass arises from the right anterior superficial part of the parotid gland.
|
|
|
The patient received 14 cycles of vincristine sulfate, 1.5 mg/m2; etoposide, 150 mg/m2; ifosfamide, 2 mg/m2; and doxorubicin hydrochloride, 20 mg/m2. The right orbit and the parotid gland region were irradiated with a total dose of 5400 rad (54 Gy) by 200-rad (2-Gy) fractions. Because there was only partial response to this treatment, the patient was referred to our center.
On our examination, the right eye had no light perception and the visual acuity in the left eye was 20/20. On the right side, there was a single large episcleral mass that was fleshy, red, immobile, painless, and hard on palpation (Figure 3). The cornea was opaque, and no fundus details could be seen. Ultrasonography failed to detect a definable intraocular solid lesion. The left eye was normal. A systemic workup failed to show any distant metastases.
|
|
|
|
Figure 3. Lack of total regression of the epibulbar and preauricular tumors 15 months later, despite radiotherapy and intensive chemotherapy.
|
|
|
A total right parotidectomy and enucleation of the right eye including the episcleral nodule were performed. Histopathologic examinations showed carcinosarcoma of the parotid gland with episcleral and in traocular metastases. The patient then received 6 cycles of cisplatin, 120 mg/m2, and fluorouracil, 1000 mg/m2. He did not have any recurrence or metastasis during 50 months of follow-up.
The excised parotid gland was firm and had nodular contours, and the cut surfaces were partly tan or creamy white (Figure 4). The globe was small and soft with a firmly adherent superior episcleral nodule (Figure 5). There were scleral thickening and posterior staphyloma formation. The site of trabeculectomy through which neoplastic tissues extended into the globe was easily identified. On light microscopy, the tumor was composed of columns of epithelial cells forming adenoid structures and islands of hypercellular cartilage (Figure 6). There were atypical chondroid cells showing pleomorphism, and the lacunae contained more than 1 nucleus, suggesting malignancy (Figure 7). Residual islands of normal parotid gland tissues were also observed. The intraocular tumor was also composed of mixed malignant chondroid and epithelial elements (Figure 8). There was no evidence of uveal tract involvement. The results of immunohistochemical and histochemical studies are shown in Table 1 and Table 2, respectively. The chondroid and epithelial cells contained abundant glycogen, and the luminal surface of epithelial cells had neutral mucin. Almost identical features were observed on reevaluation of the slides of the initial incisional biopsy, erroneously reported as rhabdomyosarcoma.
|
|
|
|
Figure 4. Gross view of the parotid gland showing the cut surface. The tumor measured 7 x 5.5 x 3.5 cm. There was no intratumoral hemorrhage or necrosis despite previous treatment.
|
|
|
|
|
|
|
Figure 5. Gross view of the enucleated eye showing the large episcleral metastatic tumor and the trabeculectomy site (arrow) through which the tumor presumably invaded the intraocular compartment.
|
|
|
|
|
|
|
Figure 6. Photomicrograph showing the epithelial-dominant part of the episcleral tumor. The epithelial cells have hyperchromic and vesicular nuclei with prominent nucleoli and eosinophilic cytoplasms. A single island of cartilage is present at the lower right of the figure (hematoxylin-eosin, original magnification x100).
|
|
|
|
|
|
|
Figure 7. Photomicrograph showing the mesenchymal-dominant part of the episcleral tumor. Many hypercellular islands of cartilage can be identified with interspersed malignant epithelial elements (hematoxylin-eosin, original magnification x40).
|
|
|
|
|
|
|
Figure 8. Photomicrograph demonstrating the intraocular tumor with both malignant chondroid and epithelial components. At the left side of the figure, disorganized retinal pigment epithelia are recognized (hematoxylin-eosin, original magnification x40).
|
|
|
|
|
|
|
Table 1. Results of Immunohistochemical Staining
|
|
|
|
|
|
|
Table 2. Results of Histochemical Staining
|
|
|
Comment
This patient underwent a series of extremely unusual events, including parotid gland malignancy with the exceptionally rare form of de novo carcinosarcoma at the age of 10 years and metastases to the orbit and epibulbar tissues, with intraocular invasion through a trabeculectomy site. Patients with malignant mixed tumor of the parotid gland usually have onset in the fifth decade of life (range, 7-86 years), with a history of a mass of 10 to 50 years' duration.5 Carcinosarcoma composes only 0.4% of all salivary gland tumors, and, by definition, both epithelial and mesenchymal components should fulfill the criteria for malignancy and typically metastasize together.3, 6 Criteria for malignancy include destruction of normal tissues, invasiveness, cellular anaplasia, pleomorphism, and atypical mitoses.2 A high-grade ductal carcinoma is the usual epithelial component, whereas chondrosarcoma is the most common mesenchymal component.2 However, fibrosarcoma, leiomyosarcoma, osteosarcoma, and rhabdomyosarcoma may also be encountered.3, 7 Our patient clearly showed definable carcinomatous and sarcomatous areas in the primary and metastatic tumors. Carcinosarcoma may also develop years after irradiation of a pleomorphic adenoma.2-3 Our case probably represents carcinosarcoma arising de novo, which is another rarity in itself.
Controversy surrounds the cell of origin of malignant mixed tumor in general and carcinosarcoma in particular. There is recent evidence that myoepithelial cells may serve as a common stem cell for both carcinomatous and sarcomatous components.8 Myoepithelial cells express keratins, vimentin, and S100.9 Tests for smooth-muscle actin and muscle-specific actin may be positive in 50% of cases, whereas tests for carcinoembryonic antigen, which indicates luminal differentiation and epithelial membrane antigen, are typically negative.9 Neoplastic chondrocytes express vimentin and are thought to develop by metaplastic myoepithelial cells.10 Our immunohistochemical staining results support these findings.
Malignant teratoid medulloepithelioma must be considered in the differential diagnosis of our case. This tumor may cause neovascular or angle-closure glaucoma, and histopathologically it may contain undifferentiated neuroblastic cells resembling retinoblastoma and heteroplastic tissues including brain, skeletal muscles, and cartilage.11 Furthermore, criteria for malignancy include uveal invasion and the presence of sarcomatous elements like chondrosarcoma, rhabdomyosarcoma, or embryonal sarcoma, among others.12 However, a carcinomatous component and the presence of both mesenchymal and carcinomatous elements at metastatic sites are not features of malignant teratoid medulloepithelioma, which shows intracranial extension rather than distant metastases in most cases.
More than 50% of patients with carcinosarcoma develop metastases, and the most common sites include lungs, liver, bones, local and hilar lymph nodes, and central nervous system.2, 7 To the best of our knowledge, orbit and intraocular structures have not been previously reported as metastatic sites. This unique case, therefore, represents a collection of exceptionally rare events and demonstrates that carcinosarcoma may occur in children and metastasize regionally as well.
The authors have no relevant financial interest in this article.
AUTHOR INFORMATION
|
Hayyam Kiratli, MD;
Hülya Gökmen Soysal, MD;
Süleyman Demir, MD
Ankara, Turkey
Corresponding author: Hayyam Kiratli, MD, Ophthalmology, Hacettepe Hastanesi Goz ABD, S hhiye 06100, Ankara, Turkey (e-mail: hkiratli{at}hacettepe.edu.tr).
REFERENCES
|
1. Batsakis JG. Malignant mixed tumor. Ann Otol Rhinol Laryngol. 1982;91:342-343.
ISI
| PUBMED
2. Gnepp DR. Malignant mixed tumors of the salivary glands: a review. Pathol Annu. 1993;28:279-328.
3. Kwon MY, Gu M. True malignant mixed tumor (carcinosarcoma) of the parotid gland with unusual mesenchymal component. Arch Pathol Lab Med. 2001;125:812-815.
PUBMED
4. Bentz BG, Hughes CA, Ludemann JP, Maddalozzo J. Masses of the salivary gland region in children. Arch Otolaryngol Head Neck Surg. 2000;126:1435-1439.
FREE FULL TEXT
5. Spiro RH, Huvos AG, Strong EW. Malignant mixed tumor of salivary origin: a clinicopathologic study of 146 cases. Cancer. 1977;39:388-396.
PUBMED
6. Spraggs PDR, Rose DSC, Grant HR, Gallimore AP. Post-irradiation carcinosarcoma of the parotid gland. J Laryngol Otol. 1994;108:443-445.
PUBMED
7. Stephen J, Batsakis JG, Luna MA, von der Heyden U, Byers RM. True malignant mixed tumors (carcinosarcoma) of salivary glands. Oral Surg Oral Med Oral Pathol. 1986;61:597-602.
PUBMED
8. Gotte K, Riedel F, Coy JF, Spahn V, Hormann K. Salivary gland carcinosarcoma: immunohistochemical, molecular genetic and electron microscopic findings. Oral Oncol. 2000;36:360-364.
PUBMED
9. Savera AT, Sloman A, Huvos AG, Klimstra DS. Myoepithelial carcinoma of the salivary glands: a clinicopathologic study of 25 patients. Am J Surg Pathol. 2000;24:761-774.
FULL TEXT
|
ISI
| PUBMED
10. Huntington HW, Dardick I. Intracranial metastasis from a malignant mixed tumor of parotid salivary gland. Ultrastruct Pathol. 1985;9:169-173.
PUBMED
11. Shields JA, Eagle RC, Shields CL, De Potter P. Congenital neoplasms of the nonpigmented ciliary epithelium (medulloblastoma). Ophthalmology. 1996;103:1998-2006.
ISI
| PUBMED
12. Broughton WI, Zimmerman LE. A clinicopathologic study of 56 cases of intraocular medulloblastoma. Am J Ophthalmol. 1978;85:407-418.
PUBMED
SECTION EDITOR: W. RICHARD GREEN, MD
|
