HISTORICAL INSIGHTS Xeroderma Pigmentosum in Four Siblings With Three Different Types of Malignancies Simultaneously in One Mohammed El-Hayek, MD,* Giles G. Lestringant, MD,† and Philippe M. Frossard, MD‡ Abstract: Xeroderma pigmentosum (XP) is a rare autosomal reces- sive disease characterized by marked sensitivity to ultraviolet radia- tion that leads to the development of multiple skin malignancies. The authors describe four XP siblings in a consanguineous Pakistani fam- ily. The first patient was a boy who died at age 2 years. The second and third siblings were girls who died at age 2 and 7 years, respec- tively. The fourth sibling, the propositus, was a boy diagnosed with XP at age 7 years. He developed three different types of malignancies simultaneously and died at age 13. The authors conclude that it is important to be aware of multiple malignancies of different types in the same patient with XP. Key Words: xeroderma pigmentosum, squamous cell carcinoma, basal cell carcinoma, DNA damage, skin neoplasms, genetics (J Pediatr Hematol Oncol 2004;26:473–475) X eroderma pigmentosum (XP) is a rare genetic disorder clinically characterized by extreme skin sensitivity to sun- light and photophobia. Genetic and molecular analyses have revealed that the repair of ultraviolet-induced DNA damage is impaired in these patients due to mutations in genes that form part of a DNA repair pathway known as nucleotide excision repair. 1,2 This provides an opportunity for mutant malignant growth. Compared with the normal population, XP patients have a more than 1,000-fold increased risk of developing can- cer on sun-exposed skin areas. 3 There are few reported patients in the literature who presented with two different malignancies simultaneously. We describe one patient who presented with squamous cell carcinoma of the left lower eyelid, basal cell carcinoma of the right ear, and multiple nodular malignant melanomas over the back and the forehead simultaneously. CASE REPORT The patient was a 7-year-old Pakistani boy who devel- oped sensitivity to sunlight manifested by freckles and dark- ened skin all over the body, with some particularly hyperpig- mented areas, and small tumors over the left lower eyelid and right ear that had developed over the few months before ad- mission. The tumor on the left eyelid was removed, and histol- ogy showed squamous cell carcinoma. The other tumor from the right ear was also removed, and histology showed basal cell carcinoma. Six months later, while he was an inpatient, other tumors appeared over the forehead, right orbital area, right preauricular area, face, neck, and back, with necrotizing and infected ulcers. The tumor from the forehead and the back were malignant melanomas (Figs. 1–4). Although he had no neurologic abnormalities at presen- tation, neurologic deterioration developed later, progressively manifested as blindness, hearing loss, ataxia, and seizures due to tumor involvement of his orbit and skull. The patient was protected from ultraviolet radiation by using sunblocks; seizures were controlled with phenytoin (5 mg/kg/d). Accutane (13-cis retinoic acid) at 2 mg/kg/d orally and 5-fluorouracil cream were started. Surgical excision of the tumors was done with skin grafting from non-light-exposed areas. The child had many admissions for infections and neu- rologic complications. Despite all efforts, his clinical condi- tion deteriorated progressively and he died at age 13. The fam- ily history disclosed that the parents were first cousins and that there had been three previous siblings with XP, all of whom died of malignant melanomas (Fig. 5). DISCUSSION The genetic background for XP is complex. The prod- ucts of the XP genes are proteins involved in the different steps of nucleotide excision repair (NER) and comprise three dam- age-recognition proteins, two helicases, and two nucleases. The two helicases, XPB and XPD, are components of the basal transcription factor, which has a role in NER and in the initia- tion of transcription. Different mutations in these genes can Received for publication December 9, 2003; accepted March 26, 2004. From the *Department of Pediatric Hematology/Oncology, Tawam Univer- sity Hospital and Faculty of Medicine and Health Sciences, Al Ain, United Arab Emirates; †Department of Dermatology, Tawam University Hospital and Faculty of Medicine and Health Sciences, Al Ain, United Arab Emir- ates; and ‡Department of Pathology, Tawam University Hospital and Fac- ulty of Medicine and Health Sciences, Al Ain, United Arab Emirates. Reprints: Mohammed El-Hayek, MD, Department of Pediatric Hematology/Oncology, Tawam Hospital, Al Ain, United Arab Emirates (e-mail: mohhayek@emirates.net.ae). Copyright © 2004 by Lippincott Williams & Wilkins J Pediatr Hematol Oncol • Volume 26, Number 8, August 2004 473