Mosaic Turner Syndrome with Y Chromosome Material and Gonadoblastoma

Previous guidelines have recommended that individuals with TS should only be tested for Y chromosome material if other symptoms indicate its presence, but new research suggests that all individuals with TS be tested for Y chromosome mosaicism (Akcan & Boduroğlu, 2021).

The standard testing used for TS is karyotyping, but it is not sensitive enough to detect the low levels of Y chromosome material that can be present in TS+Y patients (Wolff et al., 2010). Healthcare professionals should be consulted about testing options. The recommended testing method is FISH (fluorescent in-situ hybridization), although PCR testing may be an option as well (Wolff et al., 2010). It is important to note, however, that PCR testing has been found to have a higher false positive rate, so FISH should be considered the strongest standard (Wolff et al., 2019). FISH is minimally invasive and uses chemical tags to identify parts of chromosomes or genes so that pathologists can identify them visually with a microscope (Professional, 2024). 

If TS+Y material is confirmed, the main option for the prevention of gonadoblastoma is gonadectomy, the surgical removal of gonads to protect against the risk of malignancy (Dabrowski et al., 2019). This prophylactic treatment has historically been recommended at the time of diagnosis, but new research has arisen complicating the decision.  

Some research has found that keeping even nonfunctional gonads may have potential fertility benefits for patients. TS+Y material patients who do not have gonadectomy have an increased chance of spontaneous thelarche (development of breast tissue), estimated to be around 42% (Dabrowski et al., 2019). They also may have an increased chance of spontaneous menarche (menstruation), around 11% (Dabrowski et al., 2019). In this context, ‘spontaneous’ describes an event occurring randomly after typical puberty has passed. There is some research that indicates spontaneous menarche may have implications for potential fertility development, and thus makes patients better candidates for fertility preservation (Dabrowski et al., 2019). However, it is important to emphasize that this link has not yet been strongly studied or supported. 

Ultimately, the decision is up to patients and their families, though the choice is often presented at diagnosis, when parents are the main Gonadectomy may also be delayed until after puberty, though that is also around the time when the risk of malignant transformation increases. Patients and families should consult multidisciplinary healthcare professionals who can offer varied perspectives and information, such as oncologists, geneticists, fertility specialists, and primary care physicians. 

For TS+Y patients who have not undergone a gonadectomy, it may be beneficial to have regular or additional screenings for dysgerminoma, which is the most likely malignant transformation to result from gonadoblastoma. Dysgerminoma may be screened for with abdominal or intravaginal ultrasounds, as well as MRI (Mitranovici et al., 2022). Symptoms may include pelvic pain, palpable tumoral mass, amenorrhea (absence of menstrual periods), or compression of nearby organs, but it also may be asymptomatic (Mitranovici et al., 2022). Healthcare providers can direct patients to the most appropriate screening options, either regularly or due to abnormal symptoms.