Basal cell carcinoma of the conjunctiva is extremely rare. Causative factors believed to contribute to the development of basal cell carcinoma include UV light, ionizing radiation, chemical carcinogens, predisposing genetic conditions, and possibly, infection with human papillomaviruses.1 Basal cell carcinoma most commonly arises in areas of long-term sun exposure. In the ocular region, common sites include the skin of the medial canthus, lateral canthus, and lower eyelid.2 Morpheaform basal cell carcinoma is a variant of basal cell named for its clinical resemblance to a plaque of morphea (localized scleroderma). Morpheaform tumors are firm flat lesions with indistinct borders. The small strands and cords of tumor cells in morpheaform basal cell carcinoma are embedded in a dense sclerotic stroma and are virtually untouched by curettage. Morpheaform basal cell carcinoma is noted for its subclinical spread and high recurrence rate after treatment.3
Primary epithelial carcinoma of the conjunctiva is rare. It may develop from a papilloma, leukoplakia, intraepithelial epithelioma (Bowen disease), or spontaneous metaplasia.4 Primary conjunctival carcinoma is 10 times more likely to be squamous cell than basal cell.5 This report documents a rare case of intraocular extension of morpheaform basal cell carcinoma, originating from the limbal conjunctiva, in a 69-year-old man. This rare case of primary basal cell carcinoma of the conjunctiva is notable for its aggressive behavior.
A 69-year-old man, who worked as a construction worker for 30 years, reported burning and stinging of both eyes for several weeks. His medical history was notable for left-sided renal cell carcinoma treated with left-sided nephrectomy, chronic obstructive pulmonary disease, right-sided basal ganglion infarct, and hypertension. His ocular history was noteworthy only for refractive error. On ophthalmic examination, the visual acuity was noted to be 20/25 OU, and the pupils were reactive without relative afferent pupillary defect. A 6 × 6-mm, slightly elevated limbal nodule at the 3-o'clock position with overlying conjunctival hyperemia was noted in the left eye (Figure 1). In addition, the left pupil was noted to be irregularly drawn to the 3-o'clock position. Gonioscopy of the left eye revealed an open angle, except between the 2- and 4-o'clock positions, where the iris was noted to bulge forward and vessels were crossing the trabecular meshwork. Indirect ophthalmic examination showed paving-stone degeneration at the 3-o'clock position without any evidence of a mass. The working diagnosis then was ciliary body mass, including melanoma. B-scan and magnetic resonance imaging(3-mm slices) showed no abnormality of intraocular tumor.
Slitlamp view of the limbal lesion shows dilated conjunctival vessels.
Three months later, the findings of the ocular examination were unchanged. The patient refused biopsy and was lost to follow-up. One year later, the patient returned to the clinic reporting blurred vision in the left eye. The patient's visual acuity was 20/30 OD and 20/70 OS. Applanation tonometer measurement in the left eye was 68 mm Hg and iris-corneal adhesions were seen temporally. Treatment consisted of oral acetazolamide sodium, 500 mg, 1 tablet, twice daily, 0.3% metipranolol, approximately 20 µL, 1 drop in each eye twice daily, and 2% pilocarpine approximately 20 µL, 1 drop in each eye 4 times daily, was instituted with a reduction in intraocular pressure. A third B-scan revealed a ciliary body mass temporally. Findings on a second magnetic resonance image were inconclusive, and the results of an oncology workup for systemic malignancy were negative.
The patient remained resistant to surgical intervention for an additional year, during which his vision declined to no light perception, and his intraocular pressures became increasingly uncontrollable on maximal doses of the medications. Enucleation was performed approximately 2 years after the initial visit. Histopathologically, the highly invasive basal cell carcinoma was connected to the deep basal layer of the conjunctival epithelium (Figure 2) and invaded the episclera, sclera, ciliary body, trabecular meshwork, (Figure 3, Figure 4, Figure 5, and Figure 6) limbus, anterior chamber, and the collector channels. In a few areas, islands of typical basal cell carcinoma with peripheral palisading columnar cells were seen (Figure 3). Most of the lesion, however, consisted of short cords and even individual tumor cells with high nuclear cytoplasmic ratio, surrounded by dense stroma, consistent with morpheaform basal cell carcinoma (Figure 5 and Figure 6). Actinic damage of the conjunctiva in the form of severe elastotic degeneration of the collagen fibers was noted. Other histopathologic findings in the enucleated eye included peripheral anterior synechiae, atrophy of the inner retinal layers, and atrophy of the optic nerve, were consistent with glaucoma.
Note abrupt changes from normal limbal epithelium at the upper right cornea to basaloid tumor cells with hyperchromatic nuclei. There is invasion of the episclera by the neoplastic cells (hematoxylin-eosin, original magnification ×200).
Note the invasion of the episclera and sclera by the basal cell carcinoma (hematoxylin-eosin, original magnification ×50).
Higher magnification of the lesion in the episclera and sclera shown in Figure 3. The sheets of basaloid tumor cells show peripheral palisading by cuboidal to columnar cells (hematoxylin-eosin, original magnification ×100).
Ciliary body shows sheets and small nests of highly invasive basaloid tumor cells consistent with morpheaform basal cell carcinoma (hematoxylin-eosin, original magnification ×100).
Ciliary body and trabecular meshwork show highly invasive basaloid tumor cells surrounded by dense fibrous stroma, which is consistent with morpheaform basal cell carcinoma (hematoxylin-eosin, ×200).
The patient was then successfully fitted with a prosthesis. Extensive examination of periocular tissue for a primary lesion was undertaken with the biopsy of 2 suspicious lesions of the upper eyelid and left outer canthus. Histopathologic examination, however, revealed only a skin tag of the left upper eyelid and basophilic (elastotic) degeneration of the collagen fibers at the outer canthus.
Basal cell carcinoma is a malignant epithelial neoplasm of the skin, most commonly arising in areas of long-term sun exposure. It is a slow-growing tumor that rarely metastasizes but is capable of causing extensive local tissue destruction. Microscopically, buds of deeply basophilic cells protrude from the epidermis and extend into the dermis, forming large nests. Morpheaform tumors are characterized by extension into thin cords that radiate peripherally. Histopathologically, these nests and cords are enmeshed in a dense stroma of thickened collagen bundles. These characteristics make curettage ineffective as treatment; Moh micrographic surgery is the treatment of choice.1
The histogenesis of basal cell carcinoma is unclear. Many researchers believe that primary basal cell carcinoma of the conjunctiva or other mucosal surface cannot exist. They assert that basal cell carcinoma is derived from basal cells of pilosebaceous structures, and therefore, mucosal surfaces, which lack adnexal structures, could never be the site of primary basal cell carcinoma6,7 Other authors3 have held that persistent pluripotential germ cells within the deepest layers of the epidermis are somehow activated by environmental factors to produce carcinoma. In our patient, the origin of the tumor cells was the basal layer of the conjunctival epithelium. It is known that these pluripotential germ cells differentiate during embryogenesis into epithelium and adnexal structures.7 Primary conjunctival basal cell carcinoma has been rarely described in the literature. In a series of 93 comeoscleral epithelial tumors, Ash and Wilder5 described one tumor as a basal cell carcinoma. Ash8 later published the results of a larger series of 1120 patients with epibulbar tumors of which 53 tumors were listed as basal cell carcinoma. No further discussion was offered regarding the origin of the remaining limbal tumors.8 Both Aftab and Percival,9 Apte et al,10 and later Husain et al11 described primary basal cell carcinomas occurring in the nasal interpalpebral conjunctiva. Our patient had had 2 negative biopsy specimens of suspicious cutaneous lesions and has been followed up uneventfully for over 8 years. Shields et al12 recently reported a case series of 5 patients with intraocular invasion of conjunctival squamous cell carcinoma.
In summary, we report an advanced case of morpheaform basal cell carcinoma of the conjunctiva with intraocular spread and secondary glaucoma, which, to our knowledge, has not been reported. Primary basal cell carcinoma of the conjunctiva can be locally aggressive, rarely metastasize, and tend to clinically mimic papillomas. These lesions tend to occur in the actinically exposed areas of interpalpebral conjunctiva in older individuals. In our patient, we noted evidence of actinic damage in the conjunctiva and medial canthus. This finding is consistent with his job as a construction worker for 30 years with prolonged exposure to sunlight. In conjunctival tumors, ultrasonography must be performed to determine the extent of tumor spread. In the case of morpheaform basal cell carcinoma, the extent of tumor spread is difficult, but not impossible, to determine. In our patient with a blind, painful eye suspected of harboring a ciliary body tumor, enucleation seemed to be the treatment of choice.
Reprints: Melissa M. Cable, MD, 11707 Roe Ave, Leawood, KS 66211 (e-mail: mcable@discovervisioncom).
Cable MM, Lyon DB, Rupani M, Matta CS, Hidayat AA. Primary Basal Cell Carcinoma of the Conjunctiva With Intraocular Invasion. Arch Ophthalmol. 2000;118(9):1296-1298. doi: