Abstract
Aim: The clinical and histopathological characteristics of a patient with a primary basal cell carcinoma (BCC) of the right caruncle without seeding of the tumor to the conjunctiva are described. Primary basal cell carcinoma of the caruncle is an extremely rare but distinct entity. Case Report: A 24-year-old female presented with a lesion of the medial caruncle of the right eye. Clinical examination revealed a 5×2 mm, oval-shaped, brown coloured, lesion without local skin involvement. No associated cutaneous lesion was present. The tumour was completely excised. One year later, no evidence of recurrence has been noticed. Conclusion: This case describes a primary BCC of the right caruncle without seeding to the conjunctiva. It represents the first case of right caruncle BCC documented in photographs.
The lacrimal caruncle is a small oval conjunctival relief nodule located in the lacrimal fossa, medial to the plica semilunaris along the eyelid inner canthus. It is covered by a stratified epithelium similar to the skin, but without keratinization. Like the skin, it contains hair and sebaceous glands and sweat glands. But unlike the skin, it also contains accessory lacrimal glands. Its function is to retain the tear, and it forms part of the lacus lacrimalis, in passing through the puncta. Its balance is so delicate that small changes in the morphology of the lacus can cause epiphora, which may also occur after the excision of lesions. The caruncle is also involved in mucus secretion (1).
The caruncle is supplied by the superior medial palpebral arteries, its lymphatics drain into the submandibular lymph nodes, and it is innervated by the infratrochlear nerve (2).
Basal cell carcinoma (BCC) is the most common human malignant neoplasm, and accounts for nearly 80% of all non-melanoma skin cancers. It is a slow-growing, locally invasive epidermal tumor that rarely metastasizes. BCC has the potential to cause death by invasion of the central nervous system (3). Primary BCCs of mucous membranes is extremely rare. Most caruncle/ conjunctival BCCs are skin carcinomas, resulting from the local spread of adjacent neoplasms. To our knowledge, only eleven primary BCCs of the caruncle (4-14) (Table I) and four primary BCCs of the conjunctiva have been reported to date (15-18).
Case Report
A 24-year-old woman was seen by an ophthalmologist because of a slowly-enlarging lesion on the caruncle of her right eye. Neither myopia nor presbyopia were diagnosed. Visual acuity was 20/20 OU. Extraocular movements were normal, the intraocular pressures normal, and the findings from the remainder of the ocular examination were unremarkable.
The medial interpalpebral lesion measured 5×2 mm and was centered over the right caruncle (Figure 1). It was an oval-shaped, brown-coloured lesion; limits were clear and edges were regular. There was no involvement of adjacent conjunctiva or skin.
The patient had had no other previous cutaneous or visceral malignant neoplasms, and showed no signs of skin, skeletal, endocrine, or ophthalmic anomalies. There was no family history of skin cancer. The lesion had been noticed around six months earlier as a painless brown spot on the caruncle (2×1 mm). It slowly grew until it reached the volume noticed at the time of the ophthalmologist's examination.
The lesion was excised under local anaesthesia and the histopathological examination revealed a solid-type BCC, originating in the basal layer of the conjunctival epithelium: non-keratinized stratified squamous epithelium was found overlying solid lobules of basaloid cells (Figure 2). The tumour cells exhibited small round-to-ovoid hyperchromatic nuclei. The nuclei appeared relatively isomorphic. Mild mitotic activity was present. There was nuclear palisading at the periphery of the solid tumour.
The BCC was resected with a margin of safety to guarantee complete removal, no complications were encountered.
Our patient attended follow-up appointments every three months and there was no evidence of recurrence 24 months after surgical excision (Figure 3). An informed consent for the publication of these results was obtained from the patient.
Discussion
The exact origin of BCC is still controversial. The caruncle is the only part of the conjunctiva containing adnexal elements. The surface of the caruncle consists of a non-keratinized stratified squamous epithelium overlying a stroma that contains sebaceous glands, hair follicles, and, in some patients, modified lacrimal glands (of Krause), surrounded by a thin layer of fat in the center of the caruncle.
Tumours can develop from both mucous membrane and skin structures. The presence of pilar, sebaceous, apocrine, and squamous elements in BCC support the hypothesis that a pluripotential stem cell gives rise to most BCCs (3). The embryology of the caruncle is also not well -understood. It is formed at the end of the third month of gestation after the eyelids have fused. It is believed to develop either secondary to cutting-off of a portion of the lower eyelid with its appendages by the ingrowth of the lower canaliculus, or it is formed independently of the canaliculus by cellular proliferation of the epithelium on the posterior surface of the nasal lower eyelid (10).
Since 1854, when von Graefe reported the first series of lesions of the caruncle, only a few reviews have appeared, the majority of them were published more than 15 years ago (10, 19-21) and, unfortunately, some of these do not contain an accurate description of the clinical history of the diagnosed patients (9-11, 13).
The most frequent lesion among caruncle tumours is the nevus (40%) and the second is papilloma (30%). Out of these lesions, 92.5% are benign, 5% are pre-malignant and 2.5% are malignant(6). Papilloma is more common in younger people, and its importance is that it can achieve a degree of dysplasia (pre-malignancy) which would result in carcinoma in situ. Macroscopically, these kinds of lesions are friable, non-pigmented and vascularized (red-coloured), histologically they appear as fibrovascular structures surrounded by a squamous epithelium. It is not uncommon to note local invasion. Larger lesions in height and length are granulomas and chronic inflammations including angioma, although BCC and amyloidosis can also occupy 100% of the surface of the caruncle. All others are considerably less affected both in surface and height. Many studies confirm the low frequency of lesions of the caruncle and the wide variety of histological types; furthermore, malignant lesions are very uncommon. Malignant tumours that have been reported include lymphoma, melanoma, sebaceous cell carcinoma and BCC (20, 22). However, most caruncle BCCs are benign (92.5%). Cystic lesions also tend to be benign.
Preoperative view: the medial interpalpebral lesion measured 5×2 mm and was centered over the right caruncle.
Caruncular tumors generally occur with clear gender predominance, being much more common in women than in men (3:1). On the contrary, our review of the literature highlights the opposite predominance existing for BCC caruncular histotype (men:women=2:1). In terms of location, 55% of all the caruncular neoplasias were presented in the right eye and 45% in the left (14) but if we consider the previous 11 cases reporting carunclar BCC (Table I), to our knowledge, this is the first time a BCC of the right caruncle has been reported (six cases concerned the left caruncle, five do not specify the exact location of the neoplasia). Caruncular neoplasias arise in a very wide age range (14-80 years), but BCC tends to occur in younger people (mean age of 42.1 years); the BCC histotype presents a completely different trend, being reported in 9/12 patients aged 60 years or more (mean age of 61.8 years) (Table II). BCC in children or young adults tends to be associated with inherited predisposition, such as xeroderma pigmentosum, albinism, and nevoid BCC syndrome. Our patient had no clinical signs of these inheritable syndromes.
Histological examination. Baso-squamous carcinoma: non-keratinized stratified squamous epithelium was found overlying solid lobules of basaloid cells (haematoxylin and eosin, original magnification, ×4).
It must be noted that 60% of patients with BCC of the eyelid may have other BCC foci elsewhere on the face, or associated ocular injuries (23). Most BCCs arise as lesions in sun-exposed areas of the body, particularly the face. In young adults, the eyelids and nose are the most common sites of BCCs (3). The location of all well-documented primary conjunctival BCC was in the actinically exposed interpalpebral conjunctiva (15). Long-term exposure to sunlight and thus to UV light was the only significant factor predisposing to BCC observed in our patient.
The progressive growth or extent of the injury, along with increased pigmentation or colouration change is the most common reason for consultation. However, pigmentation is not a sign of malignancy. The average time of evolution prior to surgery was six months for the BCC. Most lesions have a red or brown-black colour and, although these are non-specific data, they can, together with clinical presentation, such as an increase in pigmentation or darkening, guide towards a correct clinical diagnosis.
Conclusion
This case supports previous observations that BCCs can arise from the caruncle. Lesions of the caruncle are uncommon and very diverse, which makes clinical diagnosis very difficult. Due to the enormous variety of reported cases, close collaboration between eye pathologists, dermatopathologists, surgical pathologists, and soft tissue pathologists may be needed in selected difficult cases.
Postoperative view: 24 months after surgical excision.
Keratinization, hypertrophy or retraction of the caruncle may significantly interfere with its function of mucus secretion, and may occur as a secondary dysfunction of the lacrimal drainage system. Any change in colour, size, or vascularization of a caruncular lesion should lead to excision to ensure an accurate clinical diagnosis.
The average distance between the external surface of the caruncle and the common canaliculus has been reported to be 0.85 mm, whereas the shortest distance measured is of 0.50 mm (1). Consequently, caution should be exercised when operations are performed on or near the caruncle to avoid inadvertent damage to the canalicular system.
Reported cases of caruncle primary basal cell carcinoma (BCC).
Epidemiological comparison between all caruncular neoplasias and caruncular basal cell carcinoma.
Mohs' micrographic surgery in selected cases may preserve more normal tissue than conventional surgery, with lower reported rates of recurrence (24). Radiation can be used as an adjuvant therapy to help reduce the chance of tumour recurrence or orbital invasion. Recurrences have been described even after complete excision, making long-term follow-up mandatory (even to detect the development of new primary actinically related or secondary tumours).
Acknowledgements
Special thanks are expressed to Dr. Franco Bartolomei for his help in preparing this manuscript.
All Authors hereby declare they have no potential conflicts of interest and have not received funding for this work from any of the following organisations: National Institutes of Health, Wellcome Trust, Howard Hughes Medical Institute, and other(s). Each Author participated sufficiently in the work to take public responsibility for its content.
- Received April 23, 2013.
- Revision received May 30, 2013.
- Accepted June 3, 2013.
- Copyright © 2013 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved