Ординатура / Офтальмология / Английские материалы / Tumors of the Eye and Ocular Adnexa_Char_2001

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Figure 16–14. Operative photograph (A) and axial CT (B) showing bilateral ocular colobomas with a left retro-orbital cyst. Both optic nerves have a funnel-shaped abnormality (arrows). (From Char et al.,226 with permission)

these lesions are asymptomatic and the lesions are noted by their parents. Rarely, dermoid cysts can occur in unusual locations; Howard and colleagues reported two cases where the tumor involved the lateral rectus muscle.94 These can be removed with a simple excision.95 In older children, especially from the developing countries, Echinococcus cysts of the orbit can rarely occur; in about 25 percent of these cases, there is systemic eosinophilia.96 Bone cysts are discussed later in the chapter.

RARE PIGMENTED ORBITAL TUMORS

Very rare benign infantile orbital tumors, including congenital melanocytic hamartomas, have been previously reported (Figure 16–20).97 Another uncommon pigmented tumor is the melanocytic neuroectodermal tumor of infancy (retinal anlage tumor).98,99 These tumors usually arise in the anterior maxilla, and while they can be locally invasive, they do not

Figure 16–15. Axial CT scan of enlarged cystic eye in a neonate; the opposite eye is microphthalmic.

Figure 16–16. Orbital teratoma. (From Walsh FB, Hoyt WF. Clinical neuro-ophthalmology, 3rd ed. Baltimore, MD: Williams and Wilkins; 1969.)

Figure 16–17. Meningoencephalocele produced inferior placement of the right globe. Typically, these lesions involve the superior nasal portion of the orbit.

metastasize. They occur almost exclusively in infants and can be cured with total resection. Rarely, congenital malignant melanomas can occur, and there have been 23 such reports at various body sites. A recent report documented a congenital melanoma that involved the orbit with multiple metastases.100

A number of other rare orbital tumors occur but are almost always diagnosed only on histologic examination. These include primitive neuroectodermal tumors, lipomas, hamartomas, giant cell tumors, efferent fibroglial choristomas, Zimmerman’s tumor, malignant nerve sheath tumors, and primary endodermal sinus tumors.101–107

CHILDHOOD ORBITAL MALIGNANCIES

Rhabdomyosarcoma

Rhabdomyosarcoma is the most common primary orbital malignancy, and it accounts for 5 percent of all childhood malignancies.108 It is the sixth most common cancer of childhood with an incidence of approximately four per million per year.109 It is more common in Caucasian males. This tumor was first recognized to occur in the orbit in 1882.110 The incidence of orbital involvement is variable.111 Approximately 15 to 20 percent of rhabdomyosarcomas develop in the orbit, but some reports shows that as few as 7 percent or as many as 25 percent of primaries occur at this site.

A number of molecular biologic investigations have been performed on rhabdomyosarcoma. Often,

there is a gene rearrangement between chromosomes 2 and 13, which involves the PAX3 gene located on 2q35.112 Other genomic changes have always been noted on chromosome 11.113

The mean age of presentation in orbital rhabdomyosarcoma is approximately 7.5 years, the range being birth to age 78 years.114 In our experience, orbital rhabdomyosarcoma has a bimodal pattern, it presents at either < 3 years or > 6 years.

The most common presentations of orbital rhabdomyosarcoma are ptosis or lid mass in 48 percent, proptosis in 27 percent, suspected trauma in 13 percent, or conjunctival mass in 5 percent (Figure 16–21).115,116 Most often, a mass develops in the superior nasal quadrant of the orbit, and the tumor on CT or MRI usually appears to be in or contiguous to an orbital muscle.117 Palpation of the mass is not revealing; some are fibrous or compressible from

Figure 16–20. Congenital melanocytic hamartoma that enlarged the orbit and destroyed the eye. (With permission from Char DH, Crawford JB, Ablin AR, et al. Orbital melanocytic hamartoma. Am J Ophthalmol 1981;91:357–61).

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intratumor hemorrhage. Rarely, these tumors can present with nasolacrimal duct obstructions.118

Most rhabdomyosarcomas have both rapid onset and progression of orbital proptosis. Figure 16–22 demonstrates how rapidly these tumors can grow. The CT scans in Figures 16–22A and B, taken when the patient first presented to the local ophthalmologist, demonstrate an orbital mass. Three days later, when we first saw the child (Figure 16–22C and D), an MRI showed the eye almost compressed to half its normal volume. Figure 16–23 demonstrates the typical surgical appearance of a rhabdomyosarcoma. Its texture and color are quite different from those of either lymphangioma (see Figure 16–35) or capillary hemangioma (Figure 16–11C).

The evaluation of patients with suspected orbital rhabdomyosarcoma includes either CT with computer reconstruction or MRI. At present, high-qual- ity MRI or CT scans are appropriate.117 We still prefer to detect bone invasion with CT. Vascular channels are often present in rhabdomyosarcomas and can result in enhancement on CT.119 Bone windows on CT are essential because they can demonstrate bony involvement. Figure 16–24 shows a case of rhabdomyosarcoma involving the orbital roof. Most commonly, tumor-related mortality associated

with orbital rhabdomyosarcoma occurs as a result of contiguous spread into the CNS.120 Involvement of the orbital bones is a poor prognostic sign.116,121 In a historic series of 29 cases reported by Letterman in 1976, 17 died, and the most common cause of death was contiguous spread of tumor into the middle fossa and the cranium.121 As discussed below, survival has improved even in these patients.122 Occasionally, the tumor can metastasize to the lung.

Treatment has markedly improved over the last 25 years. In 1966, Jones and co-workers reported a 45 percent cure rate of orbital rhabdomyosarcoma with aggressive surgery, usually exenteration.126 More recently, over 90 percent of tumors can be controlled with a combination of surgical debulking, approximately 50 gray (Gy) of external beam megavoltage photon irradiation and chemotherapy, depending on stage, using vincristine, cyclophosphamide, and Adriamycin.111,116,127–133 If the patient remains tumor free for over 3 years after diagnosis, recurrence is extremely unlikely.128 Even with refractory orbital rhabdomyosarcomas, long-term survival can be excellent.134 The most recent intergroup rhabdomyosarcoma study showed equally good survival without the use of alkalizing agents.122,133

Treatment of orbital rhabdomyosarcoma with a combination of surgical debulking, chemotherapy, and radiation, has historically been associated with a significant morbidity.124,135–139 In one series, 3 of 9 patients developed significant corneal ulcers.127 Abramson and co-workers reported that approximately 33 percent of eyes eventually were enucleated.116 In a later report, this group noted that 21 of 32 eyes were functionless (enucleated or blind), and only 2 had 20/50 or better vision.138 Heyn and colleagues observed 95 percent survival with orbital rhabdomyosarcoma, but cataract and lacrimal duct stenosis were common complications.135 Ninety percent of patients developed cataracts on long-term follow-up, and 50 percent developed bony orbital

Figure 16–23. View of a resected rhabdomyosarcoma. These tumors are typically whitish fibrous masses.

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Figure 16–24. Parasagittal re-formation of orbital CT showing rhabdomyosarcoma with erosion through the bony orbital roof.

hypoplasia.139 Radiation retinopathy can also develop. While cataracts eventually occurred in almost all cases of rhabdomyosarcoma, radiation retinopathy is less common (approximately 33%). Orbital bone hypoplasia is common only in young children (and less so in children > 7 years old at the time of diagnosis). While some favorable prognostic groups, including orbital tumors, have been treated without irradiation, there have been more treatment failures in those cases.140

We have not lost any eyes with orbital rhabdomyosarcoma. Additive ocular morbidity associated with the use of both chemotherapy and irradiation must be borne in mind when planning treatment of these patients.135,138 As discussed in later chapters, the use of newer radiation approaches, including intensity modulated, conformal therapy, should markedly decrease the incidence of complication noted by Heyn and others. In some of these difficult cases, the use of brachytherapy has been advocated, although the author has not had experience with it in this setting and believes that conformal therapy will be much more applicable.141,142.

Some young children have undifferentiated sarcomas that may be rhabdomyosarcoma but which cannot be definitely diagnosed on either light or electron microscopy.143 These neoplasms are treated like rhabdomyosarcoma. Rarely, a rhabdomyosarcoma will metastasize to the orbit or develop in another intraocular site.144,145,150 A malignant ectomesenchymoma is a variant of this tumor.146 A few cases of malignant rhabdoid tumors have been described in young children.147 A few reports of FNAB diagnosis for recurrent sarcomas in the orbit have been published.148

Miscellaneous Sarcomas

In the pediatric age group, other sarcomas rarely involve the orbit. Most commonly, children who develop either orbital osteogenic sarcomas or leiomyosarcomas have had bilateral retinoblastoma approximately 10 years previously.149–151 (See the chapter on retinoblastoma treatment for discussion of osteogenic sarcoma.) Any child with a history of a bilateral retinoblastoma should have yearly bone scans and evaluation by a pediatric oncologist. Any orbital swelling or pain in these children should call for prompt evaluation with either CT or MRI and, if a lesion is noted, a biopsy. Juvenile fibrosarcoma has been reported in the orbit, but it is much less common.152 The mean age of these patients is approximately 4 years. In contradistinction to the adult fibrosarcoma, in the pediatric age group, most patients fare quite well with surgical resection.

Alveolar soft part sarcoma usually occurs in the second or third decade of life, and we have managed some teenagers with this tumor. A review by Font and co-workers noted that the mean age was 23 years.153 In that series, 3 of the 17 patients developed metastases, and the preferred treatment for disease confined to the orbit was surgical resection. We have had experience with one such case. Typically, these lesions are firmly attached to a muscle and are yellowish-white in color with overlying engorged vasculature.154–156 They are managed with a combination of surgical debulking and radiation. On CT, these lesions can simulate cavernous hemangioma, as seen in Figure 16–25.157

Malignant fibrous histiocytomas can also occur in the orbit in pediatric patients. These lesions generally are relatively diffuse, and clinically, they are not diagnosed until histologic inspection of the tumor.158 (See chapter on intraconal tumors for a discussion of histiocytomas.) A benign variant, nodular fasciitis, has been reported in children, although it is more common in adults.159

CHILDHOOD SECONDARY ORBITAL

MALIGNANCIES

Retinoblastoma can occasionally present either primarily as an orbital cellulitis or as a recurrence in the orbit. Figure 12–25 in the retinoblastoma chap-

Figure 16–25. Orbital axial CT scan of biopsy-proven alveolar soft part sarcoma.

ter shows an orbital recurrence of retinoblastoma. As mentioned previously, esthesioneuroblastoma can secondarily involve the orbit. We have also observed children with systemic lymphomas and leukemias who developed preseptal orbital involvement (see Figure 16–5). As previously discussed, a number of metastases can develop in the orbit.

Benign Vascular Tumors of Childhood

Capillary hemangiomas of the orbit usually present within the first few months of life, although rarely they can become manifest at a slightly older age. In a patient > 2 years old, this diagnosis is extremely unlikely. Cavernous hemangiomas are rarely diagnosed in the first decade of life; this tumor occurs much more often in older patients (see chapter on intraconal tumors). The most frequent orbital vascular tumor presenting in children is lymphangioma. This orbital tumor was first recognized in 1868, and it accounts for 1.5 to 7 percent of orbital lesions.71,160,161 Often, the orbit is expanded as shown in Figure 16–26; any longstanding benign orbital process in early childhood can produce this picture.

The etiology, pathogenesis, and pathophysiology of orbital lymphangiomas are controversial, and Wright has questioned the terminology used to dis-

Figure 16–26. Orbital expansion secondary to lymphangioma. Any chronic expansile benign childhood orbital tumor can produce this pattern.

cuss this entity.162 What have been called lymphangiomas probably include some of these tumors and also some cases of orbital varices or other venous system malformations.163–166

An orbital varix with bleeding after trauma is shown in Figure 16–27. Usually such children present with acute proptosis after sustaining relatively minor facial trauma. Similarly, children with orbital varices often have marked increase in exophthalmos, with a Valsalva maneuver. Figure 16–28 shows a

Figure 16–27. Evacuation with a syringe of an orbital varix with bleeding secondary to trauma.

Figure 16–28. This was a large, high flow, arteriovenous malformation. At surgery portions of the orbit had findings that were very typical for a lymphangioma with a “chocolatelike” lobulated cysts.

large arteriovenous malformation that had some orbital features of a lymphangioma noted at surgery. Specifically the “chocolate-filled” cysts can be a secondary effect of massive bleeding or can develop in a lesion that has lymphoid elements.

Prior to 1959, only 34 cases of lymphangiomas were reported; Jones added 62 cases to the literature at that time.167 He noted that approximately 25 percent of orbital lymphangiomas involved only the orbit, 33 percent only the conjunctiva, and 21 percent more than one adnexal structure.

Lymphangiomas occur three times more frequently in females than in males, and all 19 cases reported by Iliff and Green occurred in the first decade of life.168 Lymphangiomas are usually diffuse and often start either in the superior nasal or inferior orbit, presenting either as a gradual onset of orbital proptosis or as acute orbital swelling during or after a viral upper respiratory infection.169

In our experience, lymphangiomas are usually diffuse lesions with multiloculated orbital choco- late-colored cysts. An example of an axial CT scan of an orbital lymphangioma is shown in Figure 16–29. Occasionally, these lesions are either confined to the conjunctiva (Figure 16–30), or they may produce a focal orbital tumor, if seen early in the disease course (Figures 16–31 and 16–32). These lesions can have various patterns on MRI scans. If there has not been recent hemorrhage, they often enhance with gadolinium and are hyperintense to brain on T2-weighted images. If there is hemorrhage,

Figure 16–29. Axial CT scan and parasagittal reconstruction showing diffuse orbital lymphangioma with intraconal and extraconal involvement but without invasion of bone.

often there is a variegated color in areas, and the pattern depends on when the bleeding occurred in relationship to the scan. (Figure 16–33). The author has removed three focal orbital lymphangiomas without recurrence. It has been the author’s clinical impression that these generally present more often in younger patients than do diffuse lymphangiomas. All three patients presented with proptosis. Rarely, these are first seen in older patients, as in the 60- year-old female shown in Figure 16–34.

Figure 16–30. Conjunctival lymphangioma.

Figure 16–31. Focal biopsy-proven lymphangioma of the orbit on axial CT scan and parasagittal reconstruction.

Rootman and co-workers classified their orbital lymphangiomas into those which are superficial, deep, or diffuse. Most lymphangiomas are diffuse at the time of presentation.170 Some of these diffuse lesions can be surgically debulked, and in some cases, the carbon dioxide laser has been used to remove portions of the tumor.171 MRI has been helpful in these cases to determine whether there is an active flow component or varix associated with the lymphangiomas.172,173 On MRI scans, in a case with hemorrhage, there are areas that are both hyperintense and hypointense to brain on T1- and T2-weighted images (Figures 16–35A and B).

Rarely, as discussed above, a lymphangioma-like pattern can also be associated with a large arteriovenous malformation.174 In the author’s experience, the management of children with diffuse orbital lym-

Figure 16–32. Axial MRI scan shows a focal lymphangioma.

Figure 16–33. Lymphangiomas that have not recently bled often enhance with gadolinium and are hyperintense to brain on T2- weighted images, as shown here.

phangiomas is often unsatisfactory. The tumor shown in Figure 16–36 was so diffuse and loculated that only portions could be removed. The presence of this lesion almost invariably results in bony enlargement of the orbit and significant cosmetic defect.

We have recently published our results with 26 orbital lymphangioma patients. These cases excluded any patient who had a vascular flow abnormality on imaging.175 In approximately 75 percent, cosmetically satisfactory results were obtained. Patients who presented with restriction of extraocular movement often had more diffuse lesions and a poorer outcome.

Occasionally, orbital lymphangiomas become so massive that they destroy the eye and produce intractable pain necessitating exenteration. Rose and Wright described 16 benign orbital lesions that required exenteration for either pain or exposure.176 An example of such a poor prognosis lymphangioma is shown in Figure 16–37. This patient had a 10-year history of a growing lymphangioma. Despite multiple resections, eventually the eye became painful and lost all light perception, and an exenteration was performed. The preoperative CT scan is shown in

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A

involve the lateral aspect of the upper lid.177 Pediatric pseudotumors diagnosed by FNAB biopsy have been reported.178 Rarer lesions which have some inflammatory component include nodular fasciitis, periorbital inflammatory myofibromatosis, and a giant cell repair of granuloma.179–181

LANGERHANS’ CELL HISTIOCYTOSIS

Histiocytic disorders of the orbit involve a spectrum of Langerhans’ cell proliferations. The older terminology, including eosinophilic granuloma, Hand- Schuller-Christian disease, and Letterer-Siwe disease, has been replaced by the classification into unifocal or multifocal eosinophilic granuloma of bone, diffuse histiocytosis-X, and malignant histiocytosis.182,183 More recently the Histiocyte Society has suggested the term Langerhans’ cell histiocytosis to encompass all these diseases.184 The etiology

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Figure 16–34. Lymphangioma presented at age 60 years. A, T1- weighted axial MRI scan. B, T2 -weighted axial MRI scan.

Figure 16–38. After exenteration and closure with a temporalis skin flap, the patient and her family were much relieved and the patient’s personality improved markedly. More commonly, orbital lymphangiomas either stabilize or show some regression in the second decade of life.

INFLAMMATORY LESIONS

Orbital pseudotumor is discussed in the chapter on orbital pseudotumors. We have seen children as young as age 6 years present with orbital myositis, a diffuse lymphoid lesion, or a lacrimal mass (Figure 16–39). The evaluation of these children is similar to that of adults. Pseudorheumatoid nodule is another variant of orbital inflammatory disease, which can present in children in the first decade of life. On ultrasonography, these lesions have a pattern consistent with a pseudotumor, and the diagnosis can be confirmed on histologic evaluation. Usually, these

A

B

Figure 16–35. A, T1-weighted image of a lymphangioma that had hemorrhage associated with tumor. B, T2 -weighted image of the case shown in Figure 16–35A.

for these abnormal proliferations of Langerhans’ cells is unknown.

The entire group of histiocytic disorders of the orbit account for < 1 percent of orbital tumors.182,185–189 Unifocal eosinophilic granuloma consists of a single bone lesion. Often, this involves the lacrimal fossa area.173,182 Clinically, the presentation of an eosinophilic granuloma is relatively typical. Usually, these patients present with an upper outer quadrant orbital swelling with pain (Figure 16–40). The differential diagnosis would include a ruptured dermoid cyst producing inflammation, an orbital pseudotumor, or metastasis; either CT or plain film radiography demonstrates a focal lytic bone lesion. The radiographic pattern is relatively typical and is characterized by smooth, clearly punched-out areas with surrounding sclerosis (Figure 16–41A). These radiographic findings are distinct from osteomas, metastatic tumors, rhabdomyosarcoma, dermoid cysts, or osteomyelitis.189

Figure 16–39. Direct coronal MRI scan demonstrating lacrimal gland involvement by a lymphoid process in a 6-year-old child.

Figure 16–37. A poor-prognosis lymphangioma; this lesion evidently destroyed vision and the eye.

Figure 16–40. Clinical photograph of unifocal eosinophilic granuloma of bone involving the lateral orbital rim.