Bilateral choroidal metastasis from carcinoma of the submandibular gland.

Metastatic tumor is the most common uveal malignancy. However, choroidal metastasis from a salivary gland neoplasm is extremely rare. We report a case of bilateral, multifocal choroidal metastasis from carcinoma of the submandibular gland.

Adenoid cystic carcinoma is a rare tumor of the head and neck. It accounts for less than 1% of all head and neck malignancies and about 10% of all salivary gland tumors.1 However, it is the most common malignancy of the submandibular gland.2 Choroidal metastasis from adenoid cystic carcinoma of the salivary gland is extremely rare. We report a case of bilateral, multifocal choroidal metastasis from adenoid cystic carcinoma of the submandibular gland.

Case History

A 56-year-old woman was referred from the palliative care unit with complaints of gradually progressive, painless decrease in vision in the left eye of one month duration and in the right eye of one week duration. She had undergone excision of a mass in the left submandibular region ten months ago. Histopathological examination showed a poorly differentiated adenoid cystic carcinoma of the left submandibular gland with extensive perineural infiltration. She underwent radiotherapy to the submandibular bed, followed by six cycles of chemotherapy with carboplatin and 5-fluoro-uracil. She developed back pain five months later due to multiple bone metastases. She was given palliative radiotherapy to the spine. Subsequently, lung and brain metastases were diagnosed.

On examination, the best corrected visual acuity was 20/40 in the right eye and 20/200 in the left eye. There was a relative afferent pupillary defect in the left eye. Anterior segment examination did not reveal any other abnormalities. Ophthalmoscopic examination of the right eye showed a yellow choroidal mass, measuring about half a disc diameter, inferior to the fovea with a minimal serous detachment of the overlying retina [Fig. 1]. There was another similar choroidal nodule just outside the superotemporal arcade [Fig 2]. Ophthalmoscopic examination of the left eye revealed an edematous disc with a yellow choroidal mass, measuring about three disc diameters, inferior to it [Fig. 3]. There was an exudative detachment of the overlying retina, which extended to the fovea. Another yellow choroidal nodule, measuring about half disc diameter, at the superotemporal arcade was noted. B-scan ultrasonography showed choroidal masses with high internal reflectivity and detachment of the overlying retina. A diagnosis of bilateral choroidal metastasis with exudative retinal detachment was made. She was advised palliative chemotherapy and radiotherapy to the orbit, brain and spine. However, the patient refused further treatment. She expired six weeks later.

Figure 1

Fundus photograph of the right eye showing choroidal nodule with minimal exudative retinal detachment at the macula

Figure 2

Fundus photograph of the right eye showing the second choroidal nodule just outside the superotemporal arcade

Figure 3

Digitally processed composite fundus photograph of the left eye showing the two choroidal nodules with exudative retinal detachment

Discussion

Metastatic tumor is the most common uveal malignancy and the choroid is the most common site for uveal metastasis.3 Although breast and lung cancers represent the most common source of choroidal metastases, malignancies of the gastrointestinal tract, kidney, prostate and skin have all been reported to metastasize to the choroid.3

Adenoid cystic carcinoma is the most common malignancy of the submandibular gland.2 Although there have been reports of choroidal metastasis from tumors of the parotid and the minor salivary glands, we are aware of only two other case reports of adenoid cystic carcinoma of the submandibular gland metastatic to the choroid.1,4 In one case, the metastasis was unilateral while in the other, both eyes were involved. In both cases, the nodules were solitary. In our case, there was bilateral involvement with two nodules in each eye. In a large survey of eyes with uveal metastases, it was noted that bilateral, multifocal presentation is less common than unilateral or unifocal presentation.3

We document a hitherto unreported case of bilateral, multifocal choroidal metastasis from submandibular gland carcinoma. The paucity of reports on this subject could be due to the practical difficulties associated with the documentation of findings in these patients who may be unable or unwilling to cooperate with tedious procedures when they are in very poor systemic condition, as was the case with our patient.