Treatment With Selumetinib for Café-au-Lait Macules and Plexiform Neurofibroma in Pediatric Patients With Neurofibromatosis Type 1.

This case report describes 4 patients with a rare autosomal dominant multisystem disorder resulting from NF1 variants that leads to café-au-lait macules and neurofibromas.

Coincidental Expression of Classic Hodgkin Lymphoma and Neurofibromatosis Type I and Literature Review.

Neurofibromatosis Type 1 (NF1) is a genetic disorder with an incidence of 1 in 2600 to 3000 individuals. It is a clinical diagnosis characterized by café-au-lait macules, neurofibromas, and axillary and/or groin freckling. Because of genetic mutations in the NF1 gene affecting the Ras/mitogen-activated protein kinase pathway, there is also risk of associated soft tissue sarcomas and hematologic malignancies. However, reports of classic Hodgkin lymphoma in patients with NF1 are sparse. We report an adolescent with NF1 who developed classic Hodgkin lymphoma. Although there is an unclear association between mutations in the NF1 gene and classic Hodgkin lymphoma, further studies are warranted.

Familial gastrointestinal stromal tumors, lentigines, and café-au-lait macules associated with germline c-kit mutation treated with imatinib.

BACKGROUND: Familial lentiginosis syndromes are characterized by a wide array of manifestations resulting from activation of molecular pathways which control growth, proliferation, and differentiation of a broad range of tissues. Familial gastrointestinal stromal tumors (GISTs) are often accompanied by additional features like hyperpigmentation, mastocytosis, and dysphagia. They have been described with mutations in c-kit (most commonly), platelet-derived growth factor receptor A, neurofibromatosis-1, and succinate dehydrogenase genes. MATERIALS AND METHODS: We report on molecular characterization and tumor histopathology of two siblings in whom lentigines and café-au-lait macules were present along with multifocal GIST. Immuhistochemical analysis of CD34 and CD117 was performed on GIST biopsy samples from both siblings, while c-kit mutational analysis was done by PCR and direct sequencing on DNA from peripheral blood leukocytes of all family members and from paraffin-embedded gastric biopsy specimens of affected siblings. RESULTS: Histopathology revealed positive expression of CD117 and CD34. Mutational analysis showed the germline c.1676T>C mutation in c-kit exon 11, (p.(Val559Ala)), in the peripheral blood of both siblings and a second exon 11 mutation, c.1669T>A (p.(Trp557Arg)) in the tumor biopsy of one of them. Initiation of imatinib treatment resulted in striking resolution of their hyperpigmentation and a stable gastrointestinal disease in one of them. CONCLUSIONS: A c-kit mutational test in familial GISTs is indicated before initiation of imatinib therapy, as it can help predict tumor response to treatment.

Partial benefit of anastrozole in the long-term treatment of precocious puberty in McCune-Albright syndrome.

We report a long-term follow-up on the use of anastrozole in the treatment of peripheral precocious puberty (PP) in McCune-Albright syndrome (MAS). A girl, age 3 years and 9 months, was diagnosed with MAS due to PP, café-au-lait spots, and polyostotic fibrous dysplasia. Serum estradiol was elevated, and gonadotropins were suppressed. Pelvic ultrasound showed an enlarged uterus and a follicle cyst (13 mm) in the left ovary. Bone scintigraphy showed osteogenic lesions on the skull, humerus, tibia, and acetabulum. Bone age was 3 years and 5 months at the chronological age of 3 years. After 36 months of treatment with anastrozole (1 mg/day), there was suppression of breast growth, normalization of growth velocity and serum estradiol, and disappearance of ovarian cysts. However, there was increase in uterine volume, advancement of bone age, and two episodes of vaginal bleeding (18th and 24th months). This report shows the partial benefit of anastrozole in the treatment of peripheral PP of girls with MAS.

McCune-Albright syndrome and the extraskeletal manifestations of fibrous dysplasia.

Fibrous dysplasia (FD) is sometimes accompanied by extraskeletal manifestations that can include any combination of café-au-lait macules, hyperfunctioning endocrinopathies, such as gonadotropin-independent precocious puberty, hyperthyroidism, growth hormone excess, FGF23-mediated renal phosphate wasting, and/or Cushing syndrome, as well as other less common features. The combination of any of these findings, with or without FD, is known as McCune-Albright syndrome (MAS). The broad spectrum of involved tissues and the unpredictable combination of findings owe to the fact that molecular defect is due to dominant activating mutations in the widely expressed signaling protein, Gsα, and the fact these mutations arises sporadically, often times early in development, prior to gastrulation, and can distribute across many or few tissues.The complexity can be mastered by a systematic screening of potentially involved tissues and cognizance that the pattern of involved tissues is established, to some degree, in utero. Thorough testing allows the clinician to establish, often times at presentation, the full extent of the disease, and importantly as well what tissues are unaffected. Treatment and follow-up can then be focused on affected systems and a meaningful prognosis can be offered to the patient and family. The authors outline screening and treatment strategies that allow for effective management of the extraskeletal manifestations of FD.

Vitamin D3 analogues improve café au lait spots in patients with von Recklinghausen's disease: experimental and clinical studies.

Topical application of vitamin D3 analogues for 6 months was found to be effective in improving the pigmentation of café au lait spots in patients with von Recklinghausen's disease. Treatment of café au lait spots grafted onto nude mice with a vitamin D3 analogue caused suppression of bromodeoxy- uridine uptake in the cells of the basal layer. Vitamin D3 analogues also decreased melanin pigment in café au lait spots after 4 weeks of treatment. Thus, it is considered that long-term application of vitamin D3 analogues is effective both for improving the pigmentation of café au lait spots and suppressing the development of neurofibromas in patients with von Recklinghausen's disease.