Shannen Doherty has shared a snap of herself about to undergo her first session of radiation therapy, and we hope she realises how important her openness is to other cancer sufferers out there. Most people don't really know what cancer treatment looks like unless they become sick, but Shannen is sacrificing her privacy to educate the world.

Shannen DohertyShannen Doherty shares cancer treatment experience

The former 'Charmed' star was diagnosed with breast cancer last year, but by 2016 the disease had spread to her lymph nodes. She has been undergoing chemotherapy and began radiotherapy for the first time yesterday (November 28th 2016), confessing how 'frightening' the experience is proving to be.

'First day of radiation treatment', she wrote. 'I look like I'm about to make a run for it which is accurate. Radiation is frightening to me. Something about not being able to see the laser, see the treatment and having this machine moving around you just scares me. I'm sure I'll get used to it but right now... I hate it.'

Shannen has been particularly open about her experiences with cancer and treatment over the last few months, sharing candid images and videos of herself undergoing chemotherapy. Last week she shared an image of herself preparing for a CT scan for her 'radiation plan'. 

'This scared me so much', she confessed in the image caption. 'Was supposed to get it with contrast but the minute they started looking at which vein to use I started crying. Full panic attack. Sometimes, you just get sick of being poked. And that's ok. I cried. I felt sorry for myself for a minute. Then stopped and reminded myself of how lucky I am. Thank God my new radiation oncologist decided to try without contrast so I would calm down.'

It's heart-warming to see the actress being so honest and outspoken about her illness. Giving fans an insight into her treatment, confessing her fears about said care and sharing pictures of herself smiling and living life to the full are actions that are more important to other sufferers than she probably realises.

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In effect, she is spreading the crucial message of hope and telling people that it's OK to be frightened even if you don't know exactly why. What a trooper.

Good luck, Shannen!