I am not a doctor. My take on this, with an assist from Google, is that the pathologist thinks this is a form of gestational trophoblastic disease (GTD). There are several types of GTD, but this pathologist isn't sure which type is present in your specimen, so they have sent it to an an expert in these diseases to get a final diagnosis.

According to Cancer Research UK:

"Gestational trophoblastic disease (GTD) is the name for abnormal cells or tumours that start in the womb from cells that would normally develop into the placenta. They are extremely rare but can happen during or after pregnancy. Most are non cancerous (benign) but some are cancerous. They are different to womb cancer."

There is more information at https://www.cancerresearchuk.org/about-cancer/gestational-trophoblastic-disease-gtd