Abstract
Individuals with hereditary cancer syndromes are at risk of developing multiple tumours and, therefore, undergo life-long surveillance procedures and risk-reducing and/or therapeutic ...surgeries. Knowledge and testing for hereditary cancer susceptibility genes is rapidly spreading, often performed at the first cancer diagnosis.
Different physical, psychosocial, ethical and economic considerations need to be taken into account when deciding on reproductive options in individuals with a hereditary cancer syndrome.
The psychosocial impact of genetic predisposition to cancer may be particularly problematic and still represents an ongoing challenge for the professional taking care of these patients. In fact, worries about passing on a genetic risk for cancer to offspring are concerns expressed by the 65% of female young adult cancer survivors when specifically interviewed.
At cancer diagnosis, fertility preservation procedures represent an effort to retain the opportunity to have genetically related children. Unfortunately, oocytes, embryo or ovarian cortex cryopreservation do not guarantee live birth. The success rates of these procedures are highly dependent on age, number of oocytes cryopreserved and may be influenced by other medical, lifestyle and (future) male factors. In addition, carriers of pathogenetic gene variants for cancer predisposition should also be thoroughly counselled about preimplantation genetic testing (PGT), a technique allowing the interruption of passing on the gene associated to cancer risk. However, this option inevitably lowers the efficacy of fertility preservation interventions in terms of future pregnancies.
Egg donation is a spreading procedure with higher success rates than fertility preservation techniques. This approach allows individuals to avoid undergoing oocytes retrieval or ovarian tissue cryopreservation surgery, thus avoiding procedural risks (infection, haemorrhage, ovarian hyperstimulation syndrome) and postponement of oncological treatments. On the other side, offspring will not have a genetic link with recipient and the beneficial psychological role of fertility preservation would be missing. In fact, several recent studies have underlined the message of hope that is indirectly perceived by oncological patients when counselled for fertility preservation. Moreover, counselling on the possibility of egg donation is challenging at the time of cancer diagnosis.
Making the right reproductive choice in carriers of hereditary cancer syndromes is a dilemma which can’t be solved generalizing. Even patients’ attitude could be different according to the time of counselling, whether is at cancer diagnosis or at the genetic predisposition diagnosis in healthy carriers. Egg donation should be considered in the available armamentarium. The complexity of the topic needs a personalized and multidisciplinary counselling.
The possibility to accelerate electron beams to ultra-relativistic velocities over short distances by using plasma-based technology holds the potential for a revolution in the field of particle ...accelerators
. The compact nature of plasma-based accelerators would allow the realization of table-top machines capable of driving a free-electron laser (FEL)
, a formidable tool to investigate matter at the sub-atomic level by generating coherent light pulses with sub-ångström wavelengths and sub-femtosecond durations
. So far, however, the high-energy electron beams required to operate FELs had to be obtained through the use of conventional large-size radio-frequency (RF) accelerators, bound to a sizeable footprint as a result of their limited accelerating fields. Here we report the experimental evidence of FEL lasing by a compact (3-cm) particle-beam-driven plasma accelerator. The accelerated beams are completely characterized in the six-dimensional phase space and have high quality, comparable with state-of-the-art accelerators
. This allowed the observation of narrow-band amplified radiation in the infrared range with typical exponential growth of its intensity over six consecutive undulators. This proof-of-principle experiment represents a fundamental milestone in the use of plasma-based accelerators, contributing to the development of next-generation compact facilities for user-oriented applications
.
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