Therapeutic challenges in treating patients with fragile X syndrome and neoplasia

A family with two cases of melanocytic tumors and fragile X syndrome

Fragile X syndrome (FXS), a leading cause of inherited intellectual disability, most commonly results from an expansion of the CGG trinucleotide repeat in the fragile X mental retardation 1 (FMR1) gene to more than 200 copies (full mutation). The FXS phenotype differs by sex and is associated with intellectual and cognitive impairment, characteristic physical features, epilepsy, and/or behavioral challenges including autism spectrum disorder. In this patient population, tumors involving blood cells, digestive organs, the central nervous system, and testes have been described, but melanocytic tumors have not been reported. Here, we describe two maternal cousins with FXS, one of whom has melanoma and the other has atypical nevus syndrome. We discuss possible mechanisms leading to this unusual or possibly coincidental association and the difficulties in the optimal treatment of FXS patients.

Breast cancer and screening in persons with an intellectual disability living in institutions in France

BACKGROUND

We aimed to describe, among a population of women with intellectual disabilities (ID) living in institutions in France, the characteristics in whom breast cancer (BC) was diagnosed and of those who participated in BC screening.

METHODS

Study was performed in 2009 among a random, representative sample of women with ID living in institutions in France. Participants answered a questionnaire either directly by themselves, or with the help of an intermediary.

RESULTS

In total, 978 women with ID aged over 18 years were included, and 14 were diagnosed with BC. The incidence observed in this sample of women with ID is similar to that of the general population (standardised incidence ratio, SIR 0.857, 95% confidence interval (CI) 0.42-1.53). Average age at diagnosis was 47.8 years, and the risk of developing BC before the age of 50 was 2.03% (0.4-3.66). This risk was not significantly different from that of the general population (2.4%, 1.0-3.78). Obesity was almost twice as frequent in women who had BC as compared to those without BC (43% vs. 22.5%, P = 0.0196). Among the 310 women aged >50 years and eligible for the national BC screening programme, 238 (77%) had already had at least one mammogram, and 199 had had it within the previous 2 years. Adherence to the screening programme was 64.2% (199/310) in the participating institutions. This rate was slightly higher than the national average of 62% for the same period.

CONCLUSIONS

The results of this study show that BC is equally as frequent among women with ID living in institutions as in the general population, and occurs at around the same age. Obesity was significantly more frequent among women in whom BC was diagnosed in our study. Participation in BC screening is slightly higher among women with ID living in institutions than among the general population.

Approach to the Diagnosis of Overgrowth Syndromes

Overgrowth syndromes comprise a group of disorders associated with excessive growth and other features such as facial dysmorphism, developmental delay or intellectual disability, congenital anomalies, neurological problems and an increased risk of neoplasia. Recent advances in understanding the genetic basis of overgrowth syndromes has resulted in a move away from clinical classification to molecular classification of overgrowth syndromes. This review provides a structured clinical approach to patients with this group of disorders and includes most of the currently known overgrowth syndromes.

Total body irradiation in a patient with fragile X syndrome for acute lymphoblastic leukemia in preparation for stem cell transplantation: A case report and literature review

Fragile X syndrome (FXS) is a congenital disorder caused by expansion of CGG trinucleotide repeat at the 5' end of the fragile X mental retardation gene 1 (FMR1) on the X chromosome that leads to chromosomal instability and diminished serum levels of fragile X mental retardation protein (FMRP). Afflicted individuals often have elongated features, marfanoid habitus, macroorchidism and intellectual impairment. Evolving literature suggests the condition may actually protect from malignancy while chromosomal instability would presumably elevate the risk. Increased sensitivity to ionizing radiation should also be predicted by unstable sites within the DNA. Interestingly, in this report, we detail a patient with FXS diagnosed with acute lymphoblastic leukemia treated with induction followed by subsequent cycles of hyper-CVAD (cyclophosphamide, vincristine, doxorubicin, dexamethasone) with a complete response who then was recommended to undergo peripheral stem cell transplantation. The patient underwent total body irradiation (TBI) as a component of his conditioning regimen and despite the concern of his clinicians, developed minimal acute toxicity and successful engraftment. The pertinent literature regarding irradiation of patients with FXS is also reviewed.