A G1P0 woman at 10 weeks gestation presents with right lower quadrant abdominal pain. She also has some nausea and vomiting, worse than her normal "morning sickness." She's lost her appetite, complains of general malaise, and has fevers and chills. On exam, palpation of the left lower quadrant causes pain in the right lower quadrant. Her WBC count is 15,000. You order an MR, and a T2 weighted image is shown below. The pathology is noted by the arrow. GS refers to the gestational sac.
Challenge: What's your diagnosis?
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