Sean CoughlanRoyal correspondent
Reuters
The King met staff and patients at the new hospital in Smethwick
King Charles joked with hospital patients about the challenges of getting older, on a visit to Birmingham.
When 85-year-old Jacqueline Page told him she was "wearing out", he told her: "That's the terrible thing I'm discovering. Bits don't work so well when you get past 70."
The King's trip to Birmingham, his first engagement of the autumn, had previously been postponed after he'd been taken ill with an adverse response to his cancer treatment.
When a patient said the King seemed to be recovering, he replied: "I'm not too bad, thank you."
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Jacqueline Page told the King she remembered his Midlands visit in the 1970s
King Charles was in Smethwick to officially open the Midland Metropolitan University Hospital.
"I'm sorry I didn't get here a few months ago," he said to staff, about when his planned visit had been postponed in March.
When he spoke to Mrs Page, she reminded him of a visit he had made to the Midlands in the 1970s - when he had flown a helicopter there.
The King said the passing of time was "terrifying".
He also spoke to Matthew Shinda, who was receiving treatment for prostate cancer, and who told the King about his delays in getting a diagnosis.
"I'm very sorry about that, it's so frustrating," said the King, who has encouraged men to get checked, after he had been diagnosed and had a procedure for an enlarged prostate last year.
The King talked about advances in treatment, but empathised that for those currently needing help there was hope, but it could still be "down the road".
The men joked about whether they could have a drink in hospital - when Mr Shinda's daughter said her father "likes his malts".
"Do they allow you a tiny dram of whisky occasionally?" asked the King. "I knew I should have brought one."
He also claimed it was "supposed to be very good for the heart".
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The King talked to Phillip Barnard about immunotherapy treatment
Phillip Barnard, being treated for lung cancer, talked to the King about receiving immunotherapy.
"That's becoming very prevalent," said the King, who asked questions about any side-effects from Mr Barnard's different types of treatment.
The hospital opened last October and the King was introduced to the first baby born there, Hernata Yonas, who arrived 90 minutes after the maternity ward had opened its doors.
There were also selfies and handshakes with patients, staff and volunteers at the hospital who had come to see the royal visitor.
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The King heard about Cardinal Newman's work at the oratory in Birmingham
Earlier in the day the King had visited the Oratory of St Philip Neri in Birmingham, founded by the 19th century Catholic theologian and philosopher, Cardinal John Henry Newman.
"I've been trying for five years to come here," he told clergy at the church.
The King has worked for many years to build bridges between faiths and had previously attended the canonisation of Cardinal Newman in Rome, when Newman was declared a saint.
The King was shown many personal items belonging to Newman and showed close interest in an original handwritten copy of the score of Elgar's The Dream of Gerontius, which was based on a Newman poem.