Any possible response Helena had been going to give to Myka's statements about the show were all wiped away by her very last statement. Four simple words, yet they carried heavy implications. It actually took a moment or two for Helena's mind to properly process the words.
Helena's first reaction was fear. Despite the time she'd spent in the modern world, she still had deeply Victorian views of many things, illness being one of them. And cancer was one of the many death sentences from Helena's time. So the fact that Myka, her best friend and the woman she loved, was saying she might have cancer frightened her to her core. And Helena Wells was rarely afraid of anything. Some of the fear she felt crept through into her eyes and body language, but she kept it in check. She didn't want to upset Myka any further than she already was.
"Cancer," Helena repeated, more to get it through her mind than anything else. Finally her brain made the connection with the television show. "That's what Claudia showed you." And that clearly must have been what Claudia said she'd tell her later.
Without further thought, Helena reached out, taking Myka's hand in her own and holding it. "Whatever you need, just ask. You aren't alone." She looked Myka in the eye, ensuring her friend understood that. But there was so much more within her eyes. The fear, the love, the uncertainty, the sadness, all of it was mixed together, all of it being able to be seen by Myka. But she kept hold of Myka's hand, keeping that contact and she hoped to convey some amount of comfort through it. Though that quickly didn't seem like enough, so without further word or hesitation, Helena leaned in and pulled Myka into a hug, closing her eyes for a couple moments and drawing in a slow breath to try and keep her emotions under control. The last thing Myka needed was for Helena to lose it right now.