A Stitch in Time Saves Nine

Luella lived her leisure life to its fullest, procrastinating like a pro.  While living large, Luella puts off what she should do today until tomorrow, or the next day, or whenever the “to do” item fits into her flow state. And so it was with her Brazilian wax; getting ready for beach season could wait. Luella also postponed scheduling a medical appointment about her irregular menstrual cycles. She preferred to ignore that her periods had become heavier than usual and that she even had vaginal bleeding between periods accompanied with pelvic pain. When Luella finally made - and kept – an appointment, her clinician noted a large mass in her perineum, specifically in her labia majora. A biopsy revealed a carcinoma consistent with endometrial cancer.

Question: There is concern that the cancer metastasized to the labia majora via lymphatics following which of the following structures?