Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.

[EX Q]: Question: Do progesterone receptor and PTEN expression predict survival in patients with low- and intermediate-grade pancreatic neuroendocrine tumors?
Answer: Combined immunohistochemical assessment of PR and PTEN may help identify a small subset of PanNETs with more aggressive behavior and may aid in risk stratification.
[EX A]: yes

[EX Q]: Question: Does incidental parathyroidectomy during thyroid surgery cause transient symptomatic hypocalcemia?
Answer: Unintended parathyroidectomy, although not uncommon, is not associated with symptomatic postoperative hypocalcemia. Modified radical neck dissection may increase the risk of incidental parathyroidectomy. Most of the glands removed were intrathyroidal, so changes in surgical technique are unlikely to markedly reduce this risk.
[EX A]: no

[EX Q]: Question: Does perforation of a nasoseptal flap increase the rate of postoperative cerebrospinal fluid leak?
Answer: Our series shows a 0% postoperative CSF leak rate in patients undergoing skull-base reconstruction with a NSF that was torn during harvest. Small tears in the NSF do not seem to affect postoperative CSF leak rates.
[EX A]:
no