In July he had a malignant one removed. Two months later, while still having radiotherapy treatment, he ran in the World Championship race, covering the 62.5 miles in 7hr 27min 57sec. He won a silver medal for his efforts, helping Great Britain finish second to Russia in the team section. To state that he deserved a gold medal for inspiration would be a gross understatement of the sparklingly obvious. Not that Sichel, 44 and a father of two, considers he has done anything exceptional.
"The thing about testicular cancer is you don't feel anything," he said. "I ran the European Championship 100km race in May and I didn't feel ill at all. But I noticed this lump in one of my testicles, went to see my doctor, and it was diagnosed as cancer. I'm a science graduate. The first thing I did when I got home was look on the Internet for everything I could find about testicular cancer. Then I rang my father. He's a doctor.
"Physiologically, you only need one testis for hormone production. The other one is for insurance. There is no great difference between having one or two. People think they might get a squeaky voice but that's not the case. And obviously some people are worried that it will affect their sense of maleness, or their sex lives, but that has never been a problem for me. I thought I would cope better if I didn't try to keep it a secret."
Bobby Moore, of course, thought differently. Only after his death did it become public knowledge that the England captain had a testicle removed two years before he lifted the Jules Rimet Trophy. Lance Armstrong, the Tour de France cyclist from the United States, and Steve Scott, holder of the American record for the mile, are other leading lights of the sporting world who have lost a testicle to cancer. "It's the most curable cancer of all," Sichel said, "but 50 per cent of sufferers leave it too late. It has spread before they seek treatment. I'm happy to talk about it because of the health education angle. There's no point running away from it."
In literal terms, Sichel is doing precisely that. A month ago he tested his fitness in a 100km track time trial. The result: 7hr 8min, just a minute short of the personal best he recorded last year. It is remarkable in itself that someone living in such a remote outpost could become an ultramarathon runner in the first place, let alone aspire to international level. At this time of year, Sichel needs three layers of clothing as he braves winds of up to 80mph to clock up 80 miles a week of training. "The wind-chill makes it about minus 20 degrees," he said, "so I wear a ski mask and smear my face with vaseline."
It was rather different in his first sporting life. He played table tennis for Scotland before packing away his bat and ball and taking up the challenge of the marathon in 1981. "I ran my first one in 2hr 43min," he recalled. "I thought, 'This is hopeless. I'm no good at this. I'm more than half an hour off the world record.'" I had no idea it was actually quite a decent time. I wish someone had told me because I packed it in. It wasn't until 1992 that I started running competitively again."
Now, Willie Sichel is getting ready to take on the world. Sanday's unheralded sporting hero is pounding the island's paths in preparation for next year's World 100km Championship race in Japan. Whatever he may achieve on the road ahead, though, the inspirational marathon man has already won his greatest victory.