Oculocutaneous manifestations in xeroderma pigmentosa

Evidence for persistent UV-induced DNA damage and altered DNA damage response in xeroderma pigmentosa patient corneas

Xeroderma pigmentosum (XP) is a rare genetic disorder characterized by injury to the ocular surface due to exposure to ultraviolet (UV) radiation. UV-induced damage in the cells leads to the formation of cyclobutane pyrimidine dimers (CPDs) and 6-4 pyrimidine-pyrimidone photoproducts that are repaired by the NER (Nucleotide Excision Repair) pathway. Mutations in the genes coding for NER proteins, as reported in XP patients, would lead to sub-optimal damage repair resulting in clinical signs varying from photo-keratitis to cancerous lesions on the ocular surface. Here, we aimed to provide evidence for the accumulation of DNA damage and activation of DNA repair pathway proteins in the corneal cells of patients with XP. Corneal buttons of patients who underwent penetrating keratoplasty were stained to quantify DNA damage and the presence of activated DNA damage response proteins (DDR) using specific antibodies. Positive staining for pH2A.X and thymidine dimers confirmed the presence of DNA damage in the corneal cells. Positive cells were found in both control corneas and XP samples however, unlike normal tissues, positive cells were found in all cell layers of XP samples indicating that these cells were sensitive to very low levels of UV. pH2A.X-positive cells were significantly more in XP corneas (p < 0.05) indicating the presence of double strand breaks in these tissues. A positive expression of phosphorylated-forms of DDR proteins was noted in XP corneas (unlike controls) such as ataxia telangiectasia mutated/Rad-3 related proteins (ATM/ATR), breast cancer-1 and checkpoint kinases-1 and -2. Nuclear localization of XPA was noted in XP samples which co-localized (calculated using Pearson's correlation) with pATM (0.9 ± 0.007) and pATR (0.6 ± 0.053). The increased presence of these in the nucleus confirms that unresolved DNA damage was accumulating in these cells thereby leading to prolonged activation of the damage response proteins. An increase in pp53 and TUNEL positive cells in the XP corneas indicated cell death likely driven by the p53 pathway. For comparison, cultured normal corneal epithelial cells were exposed to UV-radiation and stained for DDR proteins at 3, 6 and 24 h after irradiation to quantify the time taken by cells with intact DDR pathway to repair damage. These cells, when exposed to UV showed nuclear translocation of DDR proteins at 3 and 6 h which reduced significantly by 24 h confirming that the damaged DNA was being actively repaired leading to cell survival. The persistent presence of the DDR proteins in XP corneas indicates that damage is being actively recognized and DNA replication is stalled, thereby causing accumulation of damaged DNA leading to cell death, which would explain the cancer incidence and cell loss reported in these patients.

Community perspectives on the magnitude of Xeroderma pigmentosum and care-seeking practices in Micheweni district, Pemba: a mixed-methods cross-sectional study

OBJECTIVES

To determine the community's perception on the magnitude of Xeroderma pigmentosum (XP) disease and healthcare-seeking practices in Micheweni, Pemba in response to the public widespread information on the increased burden of the disease.

DESIGN

Mixed-methods cross-sectional study.

SETTING

Micheweni district, Pemba.

PARTICIPANTS

211 male and female adults in the household survey, three caretakers/parents of patients with XP in the case study, 20 key community leaders/influential people and health workers in in-depth interviews and 50 community members and other leaders in six focus groups.

RESULTS

This study has revealed that XP disease exists in few families of which some of them have more than one child affected. The record review showed that there were a total of 17 patients who were diagnosed with the disease for the past 3 years, however only 10 were alive during the time of the survey. Findings from the community members revealed that several patients were believed to have XP disease and perceived causes include inheritance, food types, beliefs and other sociocultural practices. Stigma and discrimination were reported by caretakers and religious leaders. However, some cases believed to be XP were identified as other skin conditions when clinical examination was performed by the team of our researchers. There is a great confusion about XP and other skin diseases.

CONCLUSION

The study has shown that XP affects only few families, hence termed as concentrated rather than a generalised disease. Due to the rareness of the disease, majority of people in the district are unaware of the disease, hence confusing it with other skin conditions. There is a need for the government in collaboration with other stakeholders to provide educational programme to community members about the disease to address the misconception about the magnitude of the disease.

Oral mucosa involvement in pediatric patients with xeroderma pigmentosum: a comprehensive review

BACKGROUND

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder presenting with an inability to repair UV-induced DNA damage. This can lead to the development of neoplasms affecting multiple organ systems, with onset often in childhood. Unfortunately, no cure currently exists for XP, and management strategies focus on sun protection and early intervention for malignancies. Although most skin problems in XP patients are UV induced, various oral lesions are also described. However, the literature has not extensively characterized the oral manifestations and their prognostic significance.

METHODS

We conducted a comprehensive review to evaluate the prevalence and nature of oral mucosal lesions in pediatric XP patients.

RESULTS

Our literature search yielded 130 pediatric XP patients with oral involvement and 210 associated tumoral or non-tumoral lesions. Squamous cell carcinoma was the most common type of oral mucosal tumor reported, with other malignancies including basal cell carcinoma, melanoma, angiosarcoma, fibrosarcoma, and trichilemmal carcinoma.

CONCLUSION

Given the potential morbidity and mortality associated with oral mucosal tumors in XP patients, our study aims to raise awareness of these manifestations. Early diagnosis and treatment are crucial for managing these lesions effectively, and routine oral exams should be considered a critical component of dermatological evaluations for XP patients, especially in the pediatric age group.

Pterygium-The Good, the Bad, and the Ugly

Pterygium is a multifaceted pathology that displays apparent conflicting characteristics: benign (e.g., self-limiting and superficial), bad (e.g., proliferative and potentially recurrent) and ugly (e.g., signs of preneoplastic transformation). The natural successive question is: why are we lacking reports showing that pterygium lesions become life-threatening through metastasis, especially since pterygium has considerable similarities with UV-related malignancies on the molecular level? In this review, we consider how our pathophysiological understanding of the benign pterygium pathology overlaps with ocular surface squamous neoplasia and skin cancer. The three UV-related disorders share the same initial insult (i.e., UV radiation) and responsive repair mechanisms to the ensuing (in)direct DNA damage. Their downstream apoptotic regulators and other cellular adaptations are remarkably alike. However, a complicating factor in understanding the fine line between the self-limiting nature of pterygium and the malignant transformation in other UV-related diseases is the prominent ambiguity in the pathological evaluation of pterygium biopsies. Features of preneoplastic transformation (i.e., dysplasia) are used to define normal cellular reactions (i.e., atypia and metaplasia) and vice versa. A uniform grading system could help in unraveling the true nature of this ancient disease and potentially help in identifying the earliest intervention point possible regarding the cellular switch that drives a cell’s fate towards cancer.

Ocular Surface Squamous Neoplasia Following Keratoplasty in Xeroderma Pigmentosa: A Series of Seven Cases

Purpose: To describe the clinical features and management of post-keratoplasty ocular surface squamous neoplasia (pk-OSSN) in patients with xeroderma pigmentosum (XP).Methods: Retrospective case series of seven patients with XP.Results: The mean age at diagnosis of pk-OSSN was 22 years (median, 21 years; range, 12 to 37 years). There were four males and three females. Full-thickness keratoplasty (n = 5) and Descemet stripping endothelial keratoplasty (n = 2) were performed for optical (n = 6) and therapeutic indications (n = 1). None of the patients had evidence of OSSN before or at the time of keratoplasty. The mean interval between keratoplasty and pk-OSSN was 44 months (median, 14 months; range, 3 to 109 months). The tumor epicenter was located at the limbus (n = 4), bulbar conjunctiva (n = 1) or cornea (n = 2). The mean dimension of the lesions was 12 mm (median, 11 mm; range, 6 to 18 mm). Treatment details included conjunctival/corneal tumor excision (n = 6), plaque brachytherapy (n = 3; 1 primary, 2 adjuvant) and extended enucleation (n = 1). One patient had tumor recurrence 18 months after OSSN treatment, which was treated with wide excisional biopsy. All patients are alive and free of disease over a mean follow-up period of 37 months (median, 37 months; range, 4 to 65 months).Conclusion: XP patients undergoing keratoplasty can develop OSSN several months to years after keratoplasty and require close follow-up for the same. Wide excisional biopsy with/without plaque radiotherapy is effective in the management of pk-OSSN.

Skin tumors in xeroderma pigmentosum: Evaluation of a large series and a literature review

BACKGROUND

Xeroderma pigmentosum (XP) is a rare genodermatosis with a lifelong propensity to develop malignant skin tumors.

METHODS

In this retrospective study, 24 XP patients were evaluated with regard to frequency and clinicopathological features of benign and malignant skin tumors.

RESULTS

Seventeen patients had at least one malignant skin tumor diagnosed: basal cell carcinoma (BCC) in 13 patients (n = 72), basosquamous carcinoma in three patients (n = 4), squamous cell carcinoma in six patients (n = 13), keratoacanthoma in three patients (n = 15), and melanoma in six patients (n = 18). Most melanomas (n = 15) were in situ lesions. Several benign skin tumors were noted such as tricholemmoma (n = 1), trichoepithelioma (n = 1), trichoblastoma (n = 1), follicular infundibulum tumor (n = 1), keratoacanthoma-like follicular lesion (n = 1), adnexal tumors with folliculosebaceous (n = 1) and tricholemmal differentiation (n = 1), and neurofibroma (n = 1). Benign vascular proliferations including pyogenic granulomas (n = 8), widespread telangiectasias, and senile angioma-like lesions were also observed in 3, 5, and 5 patients, respectively.

CONCLUSIONS

Similar to many reports, BCC was found to be the most common malignant skin tumor. The high prevalence of benign adnexal tumors of follicular differentiation, some of them showing mixed histopathological features and various vascular proliferations in our series raises the question of whether they indicate a formerly undescribed association with XP.

Ocular Features in a Large Cohort of Indians With Xeroderma Pigmentosum

PURPOSE

Xeroderma pigmentosum (XP) is an extreme hypersensitivity to sunlight causing skin freckling and pigmentary changes because of defective DNA repair mechanisms. The purpose of this article is to evaluate the spectrum of ocular and systemic features in XP at a tertiary eye care center in India over 32 years.

METHODS

Data from 418 eyes of 209 patients diagnosed with XP from 1987 to 2018 were reviewed retrospectively for demographics, complaints, ocular features, systemic associations, and their management.

RESULTS

Median age at diagnosis was 2 years (interquartile range, 0.5-5 years). A total of 124 patients (59.3%) were men. There was parental consanguinity in 74.4% cases. Common ocular complaints were photophobia (47.1%), ocular discomfort (45%), defective vision (36.6%), redness (13.4%), tissue growth (12%), white spot (11.2%), and pain (10.5%). At presentation, 43.5% had corneal scars (45.5% were located inferiorly and 70.9% covered visual axis). Corneal vascularization and limbal stem cell deficiency were noted in 37.4%. A total of 56% of patients had at least 1 tumor, and 6.7% had neurological abnormalities. At least 1 ocular surgery was performed in 37.8% of patients. Ophthalmic surgical interventions included tumor excision (23%), keratoplasty (13.4%), and nontumor ocular surface surgery (3.4%).

CONCLUSIONS

XP is a disorder that has high ocular morbidity in Indian patients. The recognition of common signs and symptoms and relative frequency of various ocular complications with time trends will help in managing and reducing the sequelae of this otherwise untreatable and progressive disease.

Ocular surface biopsies of patients with xeroderma pigmentosum in the United Kingdom: a retrospective observational case series

BACKGROUND/AIMS

To describe the results of all ocular surface biopsies performed on patients with xeroderma pigmentosum (XP) under the care of the UK Nationally Commissioned XP Service as well as the treatment of any subsequent ocular surface conditions diagnosed.

METHODS

Retrospective analysis of medical records. All patients with XP seen by the service from 2010 to 2019 were included and those with ocular surface biopsies were identified. Data was collected on demographics, complementation subgroup (A-G and V), biopsy details, histopathological analysis and subsequent management.

RESULTS

Of 108 patients seen in our service, 17 underwent at least one ocular surface biopsy. 45 biopsy samples were available from 13 patients of which 65% were performed on patients from complementation subgroup C (XP-C). Biopsies were categorised as either non-mapping (clinically abnormal ocular surface tissue) or mapping (multiple sites including clinically normal tissue). 67 percent of non-mapping biopsies had a mass as their indication and 46% showed ocular surface squamous neoplasia. General non-dysplastic damage was seen in 67% of non-mapping biopsies and melanocytic changes were seen in 25% of non-mapping and 81% of mapping biopsies. 47 percent of biopsy outcomes required no additional treatment but, of those that did, 50% received mitomycin C.

CONCLUSIONS

This is the largest reported series of ocular surface biopsies in patients with XP. It identifies a background of ocular surface melanocytic, degenerative and inflammatory changes, with patients with XP-C showing the most severe effects. We highlight challenges faced in interpreting their histopathology and in planning subsequent treatments.

Corneal endothelial assessment in xeroderma pigmentosum: a case-control study

PURPOSE

To analyze and compare corneal endothelial mosaic in terms of endothelial cell population, morphology and irregularity in patients with xeroderma pigmentosum (XP) with clear corneas with normal age and sex matched subjects using specular microscopy.

METHODS

Nine patients with XP without corneal involvement were evaluated in the study. An age and sex matched group of nine healthy subjects participated as control group. Evaluation of corneal endothelial layer was performed using specular microscopy.

RESULTS

Each study group consisted of five males and four females with total mean age of 28 ± 11.3 years (12-46 years). Endothelial cell density was significantly lower in patients with XP in comparison with controls (P < 0.002). Maximum and minimum cell areas were significantly higher in XP group (P < 0.016 and P < 0.029, respectively). Although central corneal thickness was higher in controls, the difference was not statistically significant (P = 0.106). Furthermore, our study showed that the patients with XP had no difference with controls in terms of coefficient of variation of cell areas.

CONCLUSIONS

This study showed that endothelial cell population can decrease in patients with XP, although other specular microscopic variables such as coefficient of variation and central corneal thickness may remain within normal values.

Bilateral Double-headed Recurrent Pterygium: A Case Presentation and Literature Review

Pterygium is a frequent corneal disease characterized by growing of fibrovascular tissue from the bulbar conjunctiva onto the cornea. Although the causes of pterygium are not obvious, sun exposure is closely correlated with its development. Pterygium, especially double-headed pterygium is mostly seen in warm climate and in individuals who work outdoors. A minority of pterygium is double-headed (both temporal and nasal origins). Bilateral recurrent double-headed pterygium is a very rare condition. Here, we reported a 35-year-old male patient with bilateral recurrent double-headed pterygium. A brief review about the recent literature concerning the etiology, associated risk factors, operation types and management of patients with recurrent pterygium was also discussed. The patient was a field worker, smoker and had a family history of pterygium. There was no ocular surgery history except pterygium surgery 15 years ago in both eyes. A successful pterygium excision was performed under local anesthesia with the vertical split conjunctival autograft transplantation (CAT) in both temporal and nasal parts of the right eye (randomly) for cosmetic disfigurement and avoidance of recurrence. The pathological report was consistent with pterygium. At postoperative first week, first and 1.5^th month visits, conjunctival autografts were in place and stable. No complications such as infection, corneal thinning or graft dislocation were seen. The patient was satisfied with his right eye and demanded the same surgery for his left eye. We suggest vertical split simultaneous CAT as a safe and useful surgical method for the treatment of recurrent double-headed pterygium; however, longer follow-up is required to confirm the outcome.

Ipsilateral presentation of ocular surface squamous neoplasia and conjunctival melanoma in xeroderma pigmentosum: A rare occurrence

A case of a 16-year-old male with xeroderma pigmentosum (XP) who presented with multiple pigmented and nonpigmented conjunctival lesions in both eyes is reported. He had a keratinized lesion at the limbus and a pigmented lesion in bulbar conjunctiva in the left eye and multiple pigmented bulbar conjunctival lesions and a keratinized limbal nodule in the right eye. Excision biopsy confirmed the diagnosis of ocular surface squamous neoplasia (OSSN) and conjunctival intraepithelial melanocytic neoplasia-2 (CIMN-2) in the right eye and OSSN and conjunctival melanoma in situ (CIMN-5) in the left eye. Two malignant conjunctival lesions occurring simultaneously in the same eye of a patient with XP have not been reported earlier.

Unusual intraoral cancer with unexpected outcome in a patient with xeroderma pigmentosum: An alert for antineoplastic treatment

Xeroderma pigmentosum (XP) is a rare autosomal disorder characterized by extreme sensitivity to ultraviolet radiation. DNA repair mechanisms are impaired, and minimal sun exposure can lead to the development of cutaneous neoplasms in very young patients. Intraoral carcinomas are uncommon and, when present, are located mainly at the tongue tip. We report an unprecedented case of squamous cell carcinoma (SCC) in the floor of mouth of a 23-year-old woman with XP. The patient was referred to the oncologist, and 2 months after surgical resection, she underwent a single session of chemotherapy plus radiotherapy. However, she died 73 hours after undergoing her first chemotherapy session. Considering the unexpected outcome of this case, we also investigated possible exacerbated adverse effects of antineoplastic treatments (especially cisplatin-based chemotherapy) in patients with XP and reviewed the main characteristics of the disease, especially cases with oral manifestations reported in the literature.

Ocular and Periocular Tumors in Xeroderma Pigmentosum: A Study of 120 Asian Indian Patients

PURPOSE

We studied the incidence, treatment, and outcome of ocular and periocular tumors in patients with xeroderma pigmentosum (XP).

DESIGN

Retrospective case series.

METHODS

This single-institution study included 120 patients with XP who underwent intervention with excisional biopsy, enucleation, or orbital exenteration. The primary outcome measures were the occurrence of eyelid or ocular surface tumor, globe salvage, locoregional and systemic metastasis, and death.

RESULTS

The mean age at presentation was 19 years. A family history of XP was present in 32 (27%) patients. Over a mean follow-up of 61 months, 34 (28%) patients developed no ocular/adnexal tumor, 86 (72%) developed ocular surface malignancy, 15 (13%) developed eyelid malignancy, and 22 (18%) developed other head and neck malignancies. Of the 86 patients with ocular surface malignancy, 48 (56%) had unilateral tumor and 38 (44%) had bilateral tumors. Invasive squamous cell carcinoma (n = 51, 41%) was the most common ocular surface tumor. Of the 15 patients with eyelid tumors, 14 (93%) had unilateral tumor and 1 (7%) had bilateral involvement. Basal cell carcinoma (n = 8, 50%) was the most common eyelid tumor. There were events of ocular surface tumor recurrence (n = 55 eyes, 44%), eyelid tumor recurrence (n = 5 eyes, 31%), locoregional lymph node metastasis (n = 3, 2%), systemic metastasis (n = 1, 1%), and death (n = 1, 1%). Overall, globe salvage was achieved in 119 (99%) patients (both eyes were salvaged in 92 [76%] patients and at least 1 eye was salvaged in 27 [23%] patients).

CONCLUSION

XP is frequently associated with ocular surface, eyelid, and other head and neck malignancies. Lifelong follow-up is mandatory in these patients.

Ophthalmic Manifestations of Xeroderma Pigmentosum: A Perspective from the United Kingdom

PURPOSE

To document the ocular manifestations of xeroderma pigmentosum (XP), presenting via the United Kingdom (UK) XP service, and to analyze the correlations between XP genotype and ophthalmic phenotype.

DESIGN

Prospective observational case series.

SUBJECTS

Eighty-nine patients seen by the UK Nationally Commissioned XP Service, from April 2010 to December 2014, with a genetically confirmed diagnosis of XP.

METHODS

Patients underwent a full ophthalmic examination at each visit. Clinical features from both eyes were recorded on a standard proforma. The most recent assessments were analyzed. A 2-tailed Fisher exact test was used to assess for differences in ocular features between patients in XP subgroups with impaired transcription coupled nucleotide excision repair (TC-NER) (category 1: XP-A, B, D, F, and G) and preserved TC-NER (category 2: XP-C, E, and V).

MAIN OUTCOME MEASURES

Lid and periocular abnormalities, ocular surface pathologies, neuro-ophthalmologic abnormalities, lens and retinal abnormalities, and visual acuity (VA).

RESULTS

Ninety-three percent of XP patients in our cohort had ocular involvement, with 65% describing photophobia. The most common abnormalities were in the periocular skin and ocular surface, including interpalpebral conjunctival melanosis (44%) and conjunctival injection (43%). Eleven percent of patients had required treatment for periocular cancers and 2% for ocular surface cancers. The most common neuro-ophthalmologic finding was minimal pupillary reaction to light (25%). Patients in category 2 had significantly more ocular surface abnormalities than patients in category 1, including a greater proportion of conjunctival injection (P = 0.003), conjunctival corkscrew vessels (P < 0.001), corneal scarring (P = 0.01) and pingueculae under the age of 50 (P = 0.02). Meanwhile, patients in category 1 had a higher proportion of poorly reactive pupils (P < 0.001) and abnormal ocular movements (P = 0.03) compared with those in category 2. Five patients (6%) presented to ophthalmologists with ocular surface signs related to XP, before any formal diagnosis of XP was made.

CONCLUSIONS

A large proportion of XP patients have ocular involvement. Regular examination by an ophthalmologist is essential, especially in screening for eyelid and ocular surface tumors. The ocular phenotype-genotype segregation within XP patients suggests that XP is a heterogeneous and complex disease. With further study, we hope to offer these patients more individualized patient care.

Xeroderma pigmentosum with bilateral ocular surface squamous neoplasia and review of the literature

Xeroderma pigmentosum is a rare genetic disorder associated with various ocular malignancies. Here we report a single paediatric case of xeroderma pigmentosum with bilateral ocular surface squamous neoplasia (OSSN) presenting with diffuse lesion in one eye and a large mass in the other eye. Diffuse OSSN in one eye was treated with topical chemotherapy using mitomycin-C (0.04%) and the large OSSN in the other eye was treated with a combination of surgery and topical chemotherapy. Long-term follow-up and a multimodality treatment approach are necessary to identify and manage recurrences of OSSN in XP.

Clinicopathological Features of Ophthalmic Neoplasms Arising in the Setting of Xeroderma Pigmentosum

BACKGROUND

Patients with xeroderma pigmentosum (XP) are strongly predisposed to the development of numerous cutaneous cancers. However, the extent of ocular pathology in these patients has not been adequately studied.

METHODS

We conducted a retrospective study of tumors involving the ocular surface and ocular adnexa from 6 XP patients. Histopathological evaluation and immunohistochemistry was performed using antibodies directed against the most common mutated proteins in XP (XPA, XPC, and XPD).

RESULTS

Patients included 4 males and 2 females with a mean age of 20.8 years (range 10-31) who met the clinical criteria for XP and were found to have a total of 13 neoplasms involving the ocular surface and adnexal skin; 6 squamous cell carcinomas (SCC), 3 cases of conjunctival intraepithelial neoplasia, 2 malignant melanomas, 1 basal cell carcinoma, and 1 atypical fibroxanthoma. Complete XPD loss was present in two tumors from 1 patient, suggesting a germline defect, and in the invasive component of an SCC from a second patient, suggesting a somatic alteration. No clear pattern of loss for XPA or XPC was evident.

CONCLUSIONS

Our study outlines our early experience with the pathology of ocular neoplasms in XP patients. These findings deserve further exploration with genetic studies and additional patients.

Genetic and environmental factors in conjunctival UV autofluorescence

IMPORTANCE

Conjunctival UV autofluorescence (CUVAF) photography was developed to detect and characterize preclinical sunlight-induced ocular damage. Ocular sun exposure has been related to cases of pterygia and was recently negatively correlated with myopia. Hence, CUVAF has excellent potential as an objective biomarker of sun exposure. However, much variation in CUVAF has been observed, and the relative contributions of genes and environment to this variation have not yet been identified.

OBJECTIVE

To investigate sources of variation in CUVAF in relation to its potential clinical relevance.

DESIGN, SETTING, AND PARTICIPANTS

We performed a cross-sectional analysis of 3 population-based cohort studies in the general community, including the Twins Eye Study in Tasmania, the Brisbane Adolescent Twin Study, and the Western Australian Pregnancy Cohort (Raine) Study. The twin studies were conducted between 2001 and 2009, and the 20-year follow-up of the Raine Study was completed between March 2010 and February 2012. We included genotypic and phenotypic data from 295 Australian families in the Tasmanian and Brisbane twin studies and from 661 participants in the 20-year follow-up of the Raine Study. We compared CUVAF levels in the 3 cohorts and performed a classic twin study to partition variation in CUVAF. We also conducted a genome-wide association analysis to identify specific genetic variants associated with CUVAF.

MAIN OUTCOMES AND MEASURES

The total area of CUVAF, heritability of CUVAF, and single-nucleotide polymorphisms (SNPs) associated with CUVAF from the genome-wide association study.

RESULTS

Within twin cohorts, individuals living closer to the equator (latitude, 27.47° S) had higher levels of CUVAF compared with individuals from southern regions (latitude, 42.88° S) (median [interquartile range], 45.4 [26.8-68.5] vs 28.7 [15.0-42.3] mm2; P < .001). The variation in CUVAF explained by the additive genetic component was 0.37 (95% CI, 0.22-0.56), whereas the variation due to the common environment was 0.50 (95% CI; 0.29-0.71). The SNP rs1060043, located approximately 800 base pairs away from the SLC1A5 gene, a member of the solute carrier family 1, had a genome-wide significant association with a P value of 3.2 × 10-8. Gene-based analysis did not improve our power to detect association with other genes.

CONCLUSIONS AND RELEVANCE

Our findings confirm that, although a large environmental component to CUVAF (equivalent of sun exposure) exists, genes also play a significant role. We identified a SNP (rs1060043) as being significantly associated with CUVAF; replication of this finding in future studies is warranted.

Atypical Fibroxanthoma of the Conjunctiva in Xeroderma Pigmentosum

BACKGROUND

Atypical fibroxanthoma (AFX) is a pleomorphic tumor that most commonly presents in the elderly and arises on sun-exposed skin.

METHODS

We report a case of a 24-year-old white male with xeroderma pigmentosum (XP), who developed an AFX of the conjunctiva, and review the literature.

RESULTS

The patient presented with a rapidly growing conjunctival mass which was surgically excised and found to be AFX. The patient has done well with no recurrence. A review of the literature was performed, and we found that only one other case has been published so far.

CONCLUSION

Patients with XP may present with unusual tumors, including nonepithelial soft-tissue tumors. AFX is a rapidly growing tumor which may rarely present on the ocular surface.

Xeroderma pigmentosum: clinicopathological review of the multiple oculocutaneous malignancies and complications

Multiple oculo-cutaneous malignancies are a common manifestation on sun-exposed facial areas in patients with Xeroderma pigmentosum (XP). Commonly seen are the basal cell carcinoma and the squamous cell carcinomas which manifest in the early first decade in contrast to fifth and sixth decade in the general population. XP manifests as photosensitivity, hyperpigmentation, premature skin aging and malignant changes like squamous cell carcinoma, basal cell carcinoma, fibrosarcoma and rarely malignant melanoma as well as internal malignancies. We report 11 cases of Xeroderma pigmentosa managed in our institute which included sex males and five females. All had photosensitivity, hyperpigmentation and consanguinity with facial malignant lesions like SCC and BCC. Ocular signs of photophobia and excessive lacrimation was seen in all the cases while blurring of vision due to corneal clouding, corneal injection, pterygium and limbal SCC were seen in 5 cases. SCC of the lids were seen in 7 cases while BCC seen in 8 cases and limbal and conjunctival SCC seen in one case. All were managed with excision while one case of melanoma with neck secondaries needed radical neck dissection while the other orbital exenteration. Oculo-cutaneous malignancies occur in the sun exposed areas so patients are advised regular follow up with speciality care. Awareness about the rare condition and importance of early detection and prevention of UV rays induced skin damage should be propagated. The disease is ultimately fatal, life can be prolonged by simple preventive measures to minimize sun exposure and early detection of the skin lesions and management.

Type I keratoprosthesis for visual rehabilitation of patients with xeroderma pigmentosum

A 6-year-old girl, a case of xeroderma pigmentosum (XP), presented with a visual acuity (VA) of 20/20 and 20/400 in the right and left eye, respectively. For a diagnosis of vascularised corneal scar, penetrating keratoplasty was performed in the left eye twice and ultimately graft failed following multiple episodes of rejection. Type I keratoprosthesis was performed in the left eye. She continues to maintain VA of 20/40 in the left eye for more than a year. Similarly, a 24-year-old man, a case of XP, presented with VA of finger counting at 1 metre in both eyes. Ocular examination showed bilateral vascularised corneal scar and conjunctivalisation. Type I keratoprosthesis was performed as primary procedure in the left eye. He maintains a VA of 20/30 for more than a year. Type I keratoprosthesis could be a primary procedure for visual rehabilitation in patients with XP with severe ocular surface disease.

Xeroderma pigmentosum: man deprived of his right to light

Xeroderma pigmentosum (XP) is a hereditary autosomal recessive disorder characterized by photo hypersensitivity of sun exposed tissues and subsequent several-fold increased risk for malignant changes resulting from impaired ability to repair UV-induced DNA damage. Estimated incidences vary from 1 in 20,000 in Japan to 1 in 250,000 in the USA, and approximately 2.3 per million live births in Western Europe. Diagnosis is made clinically by the presence of unusual sunburns or lentiginosis or onset of cancers at an early age. It is confirmed by cellular tests for defective DNA repair. Although there is no cure for XP as of now, skin problems can be ameliorated with the use of sunscreens, sun avoidance methods, and recurrent tumor excisions. Oral isotretinoin and topical application of 5-fluorouracil to treat actinic keratoses are other therapeutic options. T4N5 and photolyase liposomal lotions are innovations in the therapy of XP. Genetic counselling implicating the effect of consanguineous marriages should be considered in the management of XP patients.

Ocular manifestations of xeroderma pigmentosum: long-term follow-up highlights the role of DNA repair in protection from sun damage

OBJECTIVE

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease caused by mutations in DNA repair genes. Clinical manifestations of XP include mild to extreme sensitivity to ultraviolet radiation resulting in inflammation and neoplasia in sun-exposed areas of the skin, mucous membranes, and ocular surfaces. This report describes the ocular manifestations of XP in patients systematically evaluated in the Clinical Center at the National Institutes of Health.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Eighty-seven participants, aged 1.3 to 63.4 years, referred to the National Eye Institute (NEI) for examination from 1964 to 2011. Eighty-three patients had XP, 3 patients had XP/Cockayne syndrome complex, and 1 patient had XP/trichothiodystrophy complex.

METHODS

Complete age- and developmental stage-appropriate ophthalmic examination.

MAIN OUTCOME MEASURES

Visual acuity; eyelid, ocular surface, and lens pathology; tear film and tear production measures; and cytologic analysis of conjunctival surface swabs.

RESULTS

Of the 87 patients, 91% had at least 1 ocular abnormality. The most common abnormalities were conjunctivitis (51%), corneal neovascularization (44%), dry eye (38%), corneal scarring (26%), ectropion (25%), blepharitis (23%), conjunctival melanosis (20%), and cataracts (14%). Thirteen percent of patients had some degree of visual axis impingement, and 5% of patients had no light perception in 1 or both eyes. Ocular surface cancer or a history of ocular surface cancer was present in 10% of patients. Patients with an acute sunburning skin phenotype were less likely to develop conjunctival melanosis and ectropion but more likely to develop neoplastic ocular surface lesions than nonburning patients. Some patients also showed signs of limbal stem cell deficiency.

CONCLUSIONS

Our longitudinal study reports the ocular status of the largest group of patients with XP systematically examined at 1 facility over an extended period of time. Structural eyelid abnormalities, neoplasms of the ocular surface and eyelids, tear film and tear production abnormalities, ocular surface disease and inflammation, and corneal abnormalities were present in this population. Burning and nonburning patients with XP exhibit different rates of important ophthalmologic findings, including neoplasia. In addition, ophthalmic characteristics can help refine diagnoses in the case of XP complex phenotypes. DNA repair plays a major role in protection of the eye from sunlight-induced damage.

Cutaneous malignancies in xeroderma pigmentosum: earlier management improves survival

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease, characterized by hypersensitivity of the skin to ultraviolet (UV) radiation leading to high incidence of skin cancer and progressive neurological complications. It results in premature development of neoplasias due to an exacerbated hypersensitivity to UV radiation causing premalignant and malignant lesions leading to death in early adulthood. Two cases of clinical features of xeroderma pigmentosa with skin lesions were managed in our department. One had multiple clusters of basal and squamous cell carcinomas and the other had malignant melanomas and right neck nodes. Both were treated with multiple wide excisions and the neck node were surgically managed with radical neck dissections. Skin malignancies were common in the sun exposed areas and patients were advised regular 3 months follow up. The disease is ultimately fatal, life can be prolonged by simple preventive measures to minimize sun exposure. Comprehensive multimodality management includes patient education and counselling for the psychosomatic disorder and genetic counseling remains the most important preventive measure.

Atypical fibroxanthoma: an unusual skin neoplasm in xeroderma pigmentosum

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder related to defective deoxyribonucleic acid (DNA) repair. Various cutaneous manifestations related to ultraviolet (UV) damage characterize the clinical course. Primary malignant cutaneous neoplasms like squamous cell carcinoma, basal cell carcinoma and malignant melanoma have been reported. Atypical fibroxanthoma is a rare dermal neoplasm occurring in UV-damaged skin. We report an unusual case of atypical fibroxanthoma in a 20-year-old male with XP.

Xeroderma Pigmentosum - A case report with oral implications

Xeroderma Pigmentosum is a rare autosomal recessive genetic disorder characterized by defective DNA repair leading to clinical and cellular hypersensitivity to ultraviolet radiation and carcinogenic agents. Important clinical features are: intense cutaneous photosensitivity, xerosis, poikiloderma, actinic keratosis, acute burning under minimal sun exposure, erythemas, hyperpigmented lentiginous macules, and malignant lesions in sun-exposed areas, including basocellular carcinoma, squamous cell carcinoma, and melanoma. There is a great involvement of many parts of the body, especially head and neck. The oral manifestations are mainly related to the occurrence of malignant tumors in the lips, tongue and buccal mucosa. This paper reports a rare case of Xeroderma Pigmentosum in a 41-year-old male presenting mainly dermatological, neurological and ophthalmological involvement. Oral implications such as severe oral pain and mouth opening limitation were present due to perioral scars. In addition, this paper discuss some important aspects concerning the role of the dental professional management of this entity, since XP patients require constant dental care and follow-up in order to control the occurrence of new lesions on the lips or inside oral cavity.

Key words:Actinic cheilitis, oral involvement, Xeroderma pigmentosum.

Ultraviolet radiation and the anterior eye

The eye is on the one hand dependent on visible light energy and on the other hand can be damaged by these and the contiguous ultraviolet (UV) and infrared wavelengths. Diseases of the eye in which sunlight has been implicated have been termed the ophthalmohelioses, and these conditions pose a significant problem to the eye health of many communities. The ophthalmohelioses have a tremendous impact on patients' quality of life and have significant implications on the cost of health care. Although cataract is not entirely caused by insolation, it now seems certain that sunlight plays a contributory role-cataract extraction is one of the, if not the most, commonly performed surgical procedures in many societies. Pterygium, typically afflicting a younger population, adds a tremendous burden, both human and financial, in many countries. We review evidence that peripheral light focusing by the anterior eye to the sites of usual locations of pterygium and cataract plays a role in the pathogenesis of these conditions. Recognition of the light pathways involved with foci at stem cell niches has directed our investigations into inflammatory and matrix metalloproteinase-related pathophysiologic mechanisms. An understanding of the intracellular mechanisms involved has provided some insight into how medical treatments have been developed for the effective management of ocular surface squamous neoplasia. The concept of peripheral light focusing has also provided direction in the prevention of these diseases. This has resulted in improved sunglass design and the further development of UV-blocking contact lenses. With the development of ocular UV fluorescence photographic techniques, we have been able to demonstrate preclinical ocular surface evidence of solar damage. Evidence that diet may play a role in the development of certain conditions is reviewed. The conundrum of the public health message about solar exposure is also reviewed, and in this context, the potential role of vitamin D deficiency is summarized. The eye may play a role in the development of individualized assessment techniques of solar damage, perhaps allowing us to provide better advice to both individuals and populations.

Ophthalmic manifestations and histopathology of xeroderma pigmentosum: two clinicopathological cases and a review of the literature

Xeroderma pigmentosum is a rare, autosomal recessive disease caused by a defect in DNA repair. Patients with xeroderma pigmentosum often have cutaneous and ocular sun sensitivity, freckle-like skin pigmentation, multiple skin and eye cancers, and, in some patients, progressive neurodegeneration. Xeroderma pigmentosum predominantly affects the ultraviolet (UV) exposed ocular surface, resulting in eyelid atrophy and cancers, corneal dryness, exposure keratopathy, and conjunctival tumors. We report the clinical history and ocular pathology of two white women who had xeroderma pigmentosum with neurological degeneration: Case 1 (died at age 44 years) and Case 2 (died at age 45 years). Case 1, with mutations in the XPA gene, had more than 180 basal cell carcinomas of her skin and eyelids and died from complications of neurodegeneration. Case 2, with mutations in the XPD gene, was sun-protected and had three skin cancers. She died from complications of neurodegeneration and pneumonia. Both patients had bilateral pinguecula, corneal pannus, and exposure keratopathy. Case 1 had bilateral optic atrophy, and Case 2 had bilateral peripheral retinal pigmentary degeneration. Both patients developed retinal gliosis. The ophthalmic manifestations and pathology of xeroderma pigmentosum are discussed and reviewed with respect to this report and other cases in the literature. These cases illustrate the role of DNA repair in protection of the eyes from UV damage and neurodegeneration of the retina.

Pterygium resection with conjunctival autograft in a young child with xeroderma pigmentosum

PURPOSE

To describe the successful management of a pterygium with resection and conjunctival autograft (CAG) in a 3-year-old boy with xeroderma pigmentosum.

METHODS

A 3-year-old boy with xeroderma pigmentosum underwent primary resection and CAG for a rapidly growing pterygium.

RESULTS

At 12-month follow-up, the surgical site was well healed without recurrence and vision remained at 6/6.

CONCLUSION

Pterygium resection with CAG is a viable option in young children.

Orbital amelanotic melanoma in xeroderma pigmentosum: a rare association

Xeroderma pigmentosum (XP) is an autosomal recessive genetic disorder of DNA repair in which the body′s normal ability to repair damage caused by ultraviolet light is deficient. This leads to a 1000-fold increased risk of cutaneous and ocular neoplasms. Ocular neoplasms occurring in XP in order of frequency are squamous cell carcinoma, basal cell carcinoma and melanoma. Malignant melanomas occur at an early age in patients with XP. We report a case of XP with massive orbital melanoma in an eight-year-old boy which is unique due to its amelanotic presentation confirmed histopathologically.

Neurological symptoms and natural course of xeroderma pigmentosum

We have prospectively followed 16 Finnish xeroderma pigmentosum (XP) patients for up to 23 years. Seven patients were assigned by complementation analysis to the group XP-A, two patients to the XP-C group and one patient to the XP-G group. Six of the seven XP-A patients had the identical mutation (Arg228Ter) and the seventh patient had a different mutation (G283A). Further patients were assigned to complementation groups on the basis of their consanguinity to an XP patient with a known complementation group. The first sign of the disease in all the cases was severe sunburn with minimal sun exposure in early infancy. However, at the time the diagnosis was made in only two cases. The XP-A patients developed neurological and cognitive dysfunction in childhood. The neurological disease advanced in an orderly fashion through its successive stages, finally affecting the whole nervous system and leading to death before the age of 40 years. Dermatological and ocular damage of the XP-A patients tended to be limited. The two XP-C patients were neurologically and cognitively intact despite mild brain atrophy as seen by neuroimaging. The XP-G patients had sensorineural hearing loss, laryngeal dystonia and peripheral neuropathy. The XP-C patients had severe skin and ocular malignancies that first presented at pre-school age. They also showed immunosuppression in cell-mediated immunity. Neurological disease appears to be associated with the complementation group and the failure of fibroblasts to recover RNA synthesis following UV irradiation, but not necessarily to the severity of the dermatological symptoms, the hypersensitivity of fibroblasts to UVB killing or the susceptibility of keratinocytes to UVB-induced apoptosis.

[Ocular malignancies of xeroderma pigmentosum: clinical and therapeutic features]

BACKGROUND

Our aim was to determine the epidemiological, clinical and histopathological features as well as the most suitable therapeutic management of malignant ocular tumours in xeroderma pigmentosum based on a retrospective study of 32 patients.

PATIENTS AND METHODS

Our study was conducted in the ophthalmology unit of the Charles-Nicolle hospital between January 2001 and January 2004. A complete bilateral ophthalmologic investigation was performed for all patients and the severity of photophobia was scored on a four-point scale.

RESULTS

Thirty-two xeroderma pigmentosum patients were examined during this period. Photophobia was found in 66% of cases and 19 of 32 patients (59%) were presenting ocular and periocular malignancies. The mean age of patients was 19 years (four to 40 years). Thirty-three tumours were diagnosed in these 19 patients. Blindness was noted in 3/26 (12%) eyes in patients without malignant tumour and in 10/38 (26%) eyes in patients with malignant tumour.

CONCLUSION

Various types of malignant ocular-cutaneous tumours relating to sunlight developed in xeroderma pigmentosum patients. These disorders are more prevalent in severe and moderate forms of xeroderma pigmentosum. Lesions occur almost exclusively in the eyelids, conjunctiva, limbus and/or cornea. The rapid regression of these tumours, particularly in the cornea and limbus, may cause blindness, emphasising the importance of early management and regular monitoring of patients in order to allow early diagnosis of this condition, thereby ensuring the least mutilant treatment possible.

Atypical fibroxanthoma and squamous cell carcinoma of the conjunctiva in xeroderma pigmentosum

Patients with xeroderma pigmentosum (XP) have defective DNA repair and a high predisposition to developing abnormalities and neoplasia in the sun-exposed areas of the skin and mucous membranes. The most common tumors reported in patients with XP are squamous cell carcinomas, basal cell carcinomas, and melanomas. Atypical fibroxanthoma (AFX) is a pleomorphic tumor that arises predominantly in the sun-damaged skin of the head and neck regions of the elderly. We describe a unique case of a 6-year-old African American boy with XP who developed an atypical fibroxanthoma and 2 squamous cell carcinomas in the conjunctiva. The clinical and histopathologic findings of AFX are discussed.

Uses and complications of mitomycin C in ophthalmology

Mitomycin C is a chemotherapeutic agent that acts by inhibiting DNA synthesis. Its use and application in ophthalmology has been increasing in recent years because of its modulatory effects on wound healing. Current applications include pterygium surgery, glaucoma surgery, corneal refractive surgery, cicatricial eye disease, conjunctival neoplasia and allergic eye disease. Although it has been used successfully in these conditions, it has also been associated with significant complications. This article reviews the current trends and uses of mitomycin C in the eye and its reported complications.