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xp is clinically characterized by extreme skin photosensitivity , pigmentary anomalies of skin that is exposed to sunlight , and ophthalmic and neurological damage [ 1 , 2 ] .
the prevalence of xp is relatively high in the middle east and japan .   in africa ,
a few cases have been previously reported [ 3 , 4 ] . in this region , the more intense sun exposure predisposes people to early onset of squamous cell carcinoma despite pigmentosa protection [ 1 , 5 ] .
we report 3 cases of very advanced early - onset squamous cell carcinomas among black children with xp .
a 7-year - old phototype vi boy was admitted for a burgeoning swelling of the lower lip lasting for 3 years .
a dermatological examination revealed an ulcerative budding swelling of the lower lip ( fig 1 ) accompanied by macro - poly tumor lymph nodes under the chin and under the angulo - maxillary glands .
the diagnosis of xp was made based on the poikilodermal appearance of the sun - exposed areas .
moreover , ophthalmological examination revealed photophobia with decreased visual acuity . examinations of the anterior segment and fundus were normal .
the evolution was marked by the death of the child in a pediatric oncology department after 6 months of hospice care .
an 8-year - old phototype vi boy who was also born from first - degree blood relatives was admitted for an ulceration of the scalp that evolved over 1 year ( fig 2 ) .
this ulceration was 4 cm in diameter and had smooth edges , a clean red surface , bled on contact and was located in the right temporal - parietal region .
the child exhibited pigmentation disorders in areas that were exposed to the sun , and the condition was eased by keeping these areas covered .
the child underwent a complete surgical resection , and clinical margins greater than 6 mm were achieved .
he also received single adjuvant chemoradiation therapy ( radiotherapy and cisplatin ) 2 weeks after the intervention .
an 8-year - old , phototype vi girl was admitted for multiple ulcerative budding tumors evolving over 12 months ( fig 3 ) .
she came from a family with 4 children and parental consanguinity in the 2nd degree .
dermatological examination revealed countless ulcerative budding tumor lesions of variable size ( 16 cm ) on the midface region and scalp with extension into the left eye .
furthermore , there were dyschromic diffuse blotches , macro - poly - tumoral lymphadenopathies in the left maxillary area and an impaired general condition .
ophthalmological examination revealed a purulent lesion in the right eye , and the left eye was inaccessible due to eyelid tumors .
in a multidisciplinary meeting ( pediatric oncology , ophthalmology , and dermatology ) , the decision for neoadjuvant chemotherapy treatment for tumor mass reduction followed by oncological resection surgery was made .
the evolution was marked by the death of the child in the pediatric oncology department after her first chemotherapy treatment .
a 7-year - old phototype vi boy was admitted for a burgeoning swelling of the lower lip lasting for 3 years .
a dermatological examination revealed an ulcerative budding swelling of the lower lip ( fig 1 ) accompanied by macro - poly tumor lymph nodes under the chin and under the angulo - maxillary glands .
the diagnosis of xp was made based on the poikilodermal appearance of the sun - exposed areas .
moreover , ophthalmological examination revealed photophobia with decreased visual acuity . examinations of the anterior segment and fundus were normal .
the evolution was marked by the death of the child in a pediatric oncology department after 6 months of hospice care .
an 8-year - old phototype vi boy who was also born from first - degree blood relatives was admitted for an ulceration of the scalp that evolved over 1 year ( fig 2 ) .
this ulceration was 4 cm in diameter and had smooth edges , a clean red surface , bled on contact and was located in the right temporal - parietal region .
the child exhibited pigmentation disorders in areas that were exposed to the sun , and the condition was eased by keeping these areas covered .
the child underwent a complete surgical resection , and clinical margins greater than 6 mm were achieved .
he also received single adjuvant chemoradiation therapy ( radiotherapy and cisplatin ) 2 weeks after the intervention .
an 8-year - old , phototype vi girl was admitted for multiple ulcerative budding tumors evolving over 12 months ( fig 3 ) .
she came from a family with 4 children and parental consanguinity in the 2nd degree .
dermatological examination revealed countless ulcerative budding tumor lesions of variable size ( 16 cm ) on the midface region and scalp with extension into the left eye .
furthermore , there were dyschromic diffuse blotches , macro - poly - tumoral lymphadenopathies in the left maxillary area and an impaired general condition .
ophthalmological examination revealed a purulent lesion in the right eye , and the left eye was inaccessible due to eyelid tumors .
the child was stage t2n1m0 . in a multidisciplinary meeting ( pediatric oncology , ophthalmology , and dermatology ) , the decision for neoadjuvant chemotherapy treatment for tumor mass reduction followed by oncological resection surgery was made .
the evolution was marked by the death of the child in the pediatric oncology department after her first chemotherapy treatment .
we report 3 cases of squamous cell carcinoma in phototype vi , black african children with xp .
the patients were also remarkable for their advanced stages , which were linked to long delays in their diagnoses and severe prognoses .
consanguinity was found in our 3 observations , and this is common in west africa . in black subjects ,
squamous cell carcinomas most often occur on genodermatoses , and among these squamous cell carcinomas , we distinguish albinism , verruciform epidermodysplasia , and xp .
the peculiarity observed in our patients was the appearance of multiple de novo carcinomas ( 3 clinical cases ) in addition to the time at onset of the carcinomas and the poor prognoses .
the average age at onset of these tumors is 8 years according to kraemer and lee .
the clinical diagnosis of xp in its classic form in light - skinned individuals is easy . in our resource - limited countries
in addition to this problem , the inaccessibility of health facilities and particularly the scarcity of qualified specialists result in delays to diagnosis .
the latter factor can also be attributed to the limited number of dermatology specialists and the low socioeconomic level .
the low socioeconomic level was responsible for the delay of treatment in clinical case 3 , which had a considerable influence on the prognosis . in our series , the occurrence of the carcinomas was early , and a similar situation occurred in the study of beogo et al . .
the occurrence of squamous cell carcinoma is primarily linked to ultraviolet light exposure and strongly increased by the genetic abnormality xp [ 7 , 8 ] .
the frequencies of skin cancers in this region ( i.e. , squamous cell carcinoma , 3% ; basal cell carcinoma , 2% ; and melanoma , 1% ) are 4,800-fold greater than in a control group from the united states .
cancers occur on the most exposed areas , including the face , head , and neck in 97% of cases .
the staging was not completed in our patients due to the lack of resources . in our series , the children had eye problems .
corneal abnormalities are found in 17% of cases and lead to blindness in 12% of patients .
corneal abnormalities are also a marker of the absence of picture protection as determined in a comoros xp population . in this population ,
the clinical management of xp includes total avoidance of ultraviolet light and early excision of skin lesions with monitoring of vitamin d status . for neurological and ophthalmological manifestations ,
multidisciplinary support is needed . in all cases , it is necessary to increase the awareness of the population and increase staff training regarding these rare diseases with prognoses that may be improved if the condition is detected and managed early .
the peculiarities of our observations lie in the early occurrences in blacks , diagnostic delays , and severe prognoses of the patients .
introductionxeroderma pigmentosum is a rare autosomal recessive genetic disease . 
 this disease predisposes patients to early - onset skin cancers , particularly squamous cell carcinoma . here , we report 3 pediatric cases , including 2 deaths.observationthe subjects included 2 boys and 1 girl with skin type vi . 
 all subjects were from consanguineous marriages , and the average age was 7.6 years . 
 the patients all had ulcerative budding tumor lesions in the cephalic region , and the mean disease duration was 18 months . in all 3 cases , 
 the diagnosis of xeroderma pigmentosum was made before the poikilodermal appearance of sun - exposed areas and photophobia . 
 neurological - type mental retardation was noted in 1 case . 
 histology confirmed squamous cell carcinoma in all 3 cases . 
 the evolutions were marked by the death of 2 children ( cases 1 and 3 ) . in one case , 
 the outcome was favorable following cancer excision and subsequent chemotherapy with adjuvant radiotherapy.conclusionsquamous cell carcinoma is a serious complication related to xeroderma pigmentosum in sub - saharan africa . 
 prevention is based on the early diagnosis of xeroderma pigmentosum , black skin photoprotection , screening and early treatment of lesions , and genetic counseling .