Mother and Daughter Both Diagnosed with Colon Cancer: Immunotherapy Rewrites a 25-Year-Old's Destiny | Patient Story
In January 2024, amid Xi'an's harsh winter, Coin returned home after nearly half a month of hospital caregiving, her face etched with exhaustion.
Over 20 days earlier, Coin's mother was diagnosed with ascending colon cancer. As the only child, she took turns with her father at the hospital. Already slender, her weight dropped from over 40 kg to 37.5 kg, making her frame appear even more fragile.
Fortunately, a series of tests confirmed her mother's cancer was early-stage. With only regular follow-ups needed post-surgery, the family's heavy hearts finally settled.
At that time, she had no idea that fate would knock again five months later—the same cancer, the same hospital, the same ward. Only this time, she transitioned from caregiver to patient.
At 25, Coin's life was steadily progressing along the expected path of graduation, career, and marriage. Yet, at a critical juncture in her graduate studies, everything was put on pause. Forced to rapidly assume roles she never imagined, she had to turn onto an unfamiliar path of self-rescue.
Author | Dun'er
Editor | Dun'er
Reviewer | Guangguang
「 I. The Mystery of dMMR/MSI-H 」
"Is school busy? Can you come home early?"
Coin still remembers that call on New Year's Eve 2024. Her mother's words were evasive. Later, her cousin called to reveal: a tumor was found during her mother's colonoscopy.
This wasn't the family's first cancer diagnosis. Years ago, Coin's grandfather passed away from stomach cancer, and her uncle was diagnosed with it a few years back, now six years post-surgery. "I didn't know about our family history back then. I was too young to even realize my grandfather died of stomach cancer."
After diagnosis, her mother was quickly transferred to Xijing Hospital of Air Force Medical University and successfully underwent radical surgery for colon cancer. The postoperative pathology report staged it as T2N0M0, indicating early-stage colon cancer. Per clinical guidelines, no adjuvant therapy was needed, only regular follow-ups.
Post-surgery, her mother completed immunohistochemistry and genetic testing, revealing dMMR (mismatch repair deficiency) / MSI-H (microsatellite instability-high). At the time, Coin didn't grasp the deeper implications of these hereditary markers—though they account for only 10%-15% of colorectal cancer cases, they are closely linked to familial tumor development.
Upon discharge, the doctor specifically advised Coin, "You must make regular colonoscopies a routine after age 40."
「 II. Reconnecting with the 'Panda Group' 」
Just five months later, this seemingly distant test result intertwined with Coin's life once again.
In March 2024, Coin was treated for acute appendicitis at Xi'an Chang'an District Hospital. During surgery, doctors unexpectedly noticed significant intestinal swelling and recommended a follow-up colonoscopy.
Two months later, as Coin woke from the colonoscopy anesthesia, her first instinct was to seek answers from the doctor. "I already had a feeling. The doctor tried to reassure me, but the moment my mother said she'd take me to Xijing Hospital for treatment, I knew something was wrong."
Coin was already naturally thin, accompanied by unexplained anemia, and her previous intestinal cramps had been dismissed as gastroenteritis by the school doctor... When the colonoscopy report came out, these scattered clues suddenly formed a devastating answer.
Coin fell into brief confusion and anxiety. As relatives flooded into her ward, a sudden thought crossed her mind: "Am I not going to live long?"
Fortunately, Coin considers herself naturally optimistic. Since it had happened, she didn't need extra encouragement, only a proactive attitude. After deciding on treatment, Director Li from Chang'an District Hospital helped connect her with Director Zheng at Xijing Hospital—the very same doctor who had operated on her mother five months prior.
Coin recalled that her mother recovered well post-surgery, giving the family great confidence. Thus, Coin stepped into that familiar corridor for the second time.
During her hospital stay awaiting surgery, Coin remembered "Panda and Friends."
When her mother was ill, she had come across information online about this "largest digestive tract tumor patient mutual aid organization in China," which gathers tens of thousands of people in similar situations. Following the guide, she found the WeChat Official Account entry and added a group volunteer. "Back then, since my mother's final pathology report hadn't come out and her overall prognosis was good without needing chemo, I thought the matter was settled and put joining the group on hold."
This time, she submitted her medical records without hesitation. After detailing her condition and family history to the volunteer, she was quickly added to the Lynch syndrome group.
「 III. Surgery or Immunotherapy: That Is the Question 」
"All colorectal and gastric cancer patients should know what MMR is... For newly diagnosed patients, Panda Group volunteers always recommend completing immunohistochemistry and genetic testing." In June 2025, an online live Q&A session on MSI-H and Lynch syndrome was held.
MSI-H (microsatellite instability-high) is a molecular characteristic of tumors. Lynch syndrome, a hereditary cancer predisposition syndrome, often causes tumors to exhibit MSI-H features due to germline mutations in mismatch repair genes. Therefore, MSI-H serves as a crucial screening indicator for Lynch syndrome.
Within the Panda Group, although MSI-H patients are not the majority, over 4,000 individuals are currently distributed across nine Panda MSI-H Lynch groups.
After joining, Coin carefully read the group announcement's "Beginner's Guide to Microsatellites and Lynch." At the time, she lacked key evidence for a formal Lynch syndrome diagnosis, but the details in "A Middle-Aged Beijinger's Battle Against Advanced Colon Cancer" reminded her of her family's successive cancer "curses." Her suspicion that she might be a Lynch patient grew clearer.
How could she confirm it? Coin posted her question in the group. Volunteers quickly stepped up to help.
"They told me not to rush into surgery, but to first complete immunohistochemistry and genetic testing to see if my results matched my mother's." Through fellow patients' experiences, Coin learned for the first time that MSI-H tumors can respond well to immunotherapy.
Sunshine, Shenka, Sister Wan... Over those few days, group volunteers provided her with detailed answers. This girl, who knew nothing about cancer, slowly built a cognitive framework for understanding Lynch syndrome.
Guided by group members, Coin completed her immunohistochemistry and genetic testing. Meanwhile, to secure a clear treatment direction, she made a bold decision: emailing Professor Ding from Sun Yat-sen University Cancer Center. "I often heard the group mention Professor Ding, so I read his papers, found his email, and thought I'd give it a try. Even if he didn't reply, I had nothing to lose."
Three or four days later, Professor Ding indeed replied with a detailed email, explaining the feasibility of neoadjuvant therapy before surgery and sharing his assistant's WeChat contact.
"Professor Ding's assistant mentioned a suitable clinical trial group in Guangzhou and suggested I consider treatment there." Considering distance and financial aspects, the assistant later recommended a suitable local group in Xi'an. However, after learning about the protocol, Coin decided to decline.
"In that trial, the control group underwent direct surgery, while the experimental group received two cycles of dual immunotherapy (CTLA-4 inhibitor combined with sintilimab) before surgery."
By then, Coin had been in the Panda Group for a few days and read many fellow patients' treatment journeys. She had formed her own plan: "If my subtype is suitable for immunotherapy, I don't want to miss the chance to try it first. If I'm randomly assigned to the control group and have to undergo surgery immediately, wouldn't that waste a potentially better treatment option?" Based on this concern, Coin ultimately politely declined the trial enrollment.
「 IV. Immunotherapy on the Agenda 」
While waiting for test results, Coin experienced sudden, unexplained abdominal pain. It was likely the hardest moment of her life, giving her a direct taste of the despair brought by illness. "It felt like something was tearing at you, making every breath excruciating. I even thought if every day from then on would be this painful, I wouldn't want to live anymore."
Urged by group members, Coin rushed to Xijing Hospital's emergency department overnight. After a series of tests ruled out bowel obstruction, doctors decided to admit her for further evaluation. Fortunately, the next day, her immunohistochemistry and genetic test results brought a turning point: dMMR/MSI-H, meeting the criteria for immunotherapy.
After thorough communication with her primary care team, immunotherapy was immediately scheduled.
When choosing medication, Coin considered her own situation and referenced group members' experiences, ultimately opting for the domestic drug sintilimab. "Everyone in the group said domestic drugs work just as well and are more cost-effective."
To her surprise, her abdominal pain eased that very afternoon and vanished completely the next day. "Normally, drugs don't work this fast. I feel incredibly lucky."
「 V. Immunotherapy Unlocks cCR 」
"With breakthroughs in immunotherapy, about 70% of dMMR/MSI-H patients can achieve clinical complete response (cCR) through immunotherapy, offering the possibility of organ preservation or even avoiding surgery, but this requires strict evaluation via colonoscopy, digital rectal exam, and MRI." In November 2025, Professor Peirong Ding shared this professional insight during a live stream, perfectly aligning with Coin's core treatment goal.
At the time, Coin closely followed discussions on cCR evaluation in the group. Fellow patients' experiences and doctors' emphasized criteria helped her gradually understand that for young MSI-H patients like herself, cCR not only signified treatment success but also offered a chance at cure without surgery—crucial for someone with a naturally frail constitution.
In the winter of 2024, after her eighth treatment cycle, she decided to travel to Guangzhou for an evaluation with Professor Peirong Ding.
During immunotherapy, doctors informed her via CT scans that the tumor had shrunk significantly and the treatment was highly effective. Yet, as the evaluation date approached, Coin's anxiety surged. "I wanted to know the immunotherapy results and fight for the possibility of avoiding surgery. I'm too thin; both my mom and the doctors worried I couldn't withstand surgery."
On the day of the evaluation, Professor Ding's gentle yet firm words finally put her mind at ease: "Your tumor has completely regressed. You can choose surgery, or you can choose active surveillance."
Returning from Guangzhou, Coin continued her routine hospital visits for each treatment cycle. After the cCR evaluation, she jokingly referred to her hospital trips as "going to work." However, due to increasingly severe rash side effects, she concluded her treatment after the eleventh cycle.
[ Comparison of colonoscopy reports before and after treatment. Coin says, "This is the power of PD-1." ]
「 VI. Unlocking New Life Roles: From Patient to Volunteer 」
"Director Li at Chang'an District Hospital, whom I barely knew, enthusiastically helped me connect with experts at Xijing Hospital. The doctors and nurses in Xijing's gastrointestinal surgery department always chatted with me during treatments, easing my stress. And Dr. Liu Fangqi from Fudan University Shanghai Cancer Center, recommended by a group member, reviewed my scans for free. I consulted him online many times, and he always answered in great detail."
Coin always says the Panda Group changed her destiny. Without joining, she would likely have been rushed into surgery long ago, possibly with a completely different outcome.
"Later, I asked my doctor and learned my initial stage was T4B, with adhesions to the abdominal wall. If I had undergone surgery back then, it likely wouldn't have been completely resected. That's why I believe completing immunohistochemistry and genetic testing before surgery is essential. Even just an immunohistochemistry test can open up possibilities."
After concluding treatment, Coin signed up as a group volunteer, answering questions for new patients in Lynch Group 8. However, the group was newly formed, and there were more volunteers than patients. "Sometimes before I finished typing, someone else had already replied. Later, facing graduation and a busy schedule, I stopped answering questions and just occasionally checked the group. I'll definitely return to help everyone after graduation!"
From "patient's family member" to "patient herself," and finally to a fully recovered "Panda Group volunteer" holding an umbrella for others, in less than half a year, Coin unlocked many life roles she never imagined.
Is it more stressful to be a caregiver or more agonizing to be a patient? Coin and her mother share the same answer: "Definitely the caregiver." Within half a year, this family of three suddenly had two cancer patients. The heavy blows of life were steadily caught by Coin's father. Serving as a caregiver twice in a row, the agony and pressure are unimaginable.
In Coin's view, the pressure and inner torment borne by loved ones far outweigh the physical pain of illness. "When you're sick yourself, you don't have as many distracting thoughts; you just cooperate with treatment. But when a family member is sick, your heart is in your throat every day, worrying about disease progression and calculating treatment costs. Now my mom and I can care for each other at home, but my dad still has to work to support us. The family relies on his income, leaving him no time to feel down."
Before her illness, Coin's days were like a straight line, repeating the routine from dorm to lab, playing games in bed when free. Now, her life is suddenly filled with uncertainties. For instance, nearing graduation, finding a job that "fits" her physical condition seems quite difficult.
"I used to feel the world didn't really need me, but after getting sick, I feel I haven't seen enough of it yet." In her twenties, the future should have been like a buffet, but she can only order "the few dishes she can digest."
Even so, she views her current life as a "limited-time blind box": "Every extra day opened brings another day of surprises."
To protect patient privacy, names in this article are pseudonyms.
Images featuring the patient's portrait are used with authorization and may not be used without permission.
Patient Stories | Click text to jump
A Middle-Aged Beijinger's Battle Against Advanced Colon Cancer | Walking with Gastric Cancer: Brother Zhuzi's Brilliant Life | Aming: Two Years Accompanying My Mom Through Colon Cancer with Liver and Lung Metastases | In Memory of A-Xing: He Crossed the Night Sky Like a Meteor, Illuminating Countless Dark Nights | Sibling Bond: Four Years of Treatment for Colon Cancer with Liver Metastasis | Xiao Li: A Patient's Self-Narrative of Fighting Cancer | Sister Xiuxiu: Treatment Journey for Colon Cancer with Liver and Ovarian Metastases | Brother Guo: Tenacious Treatment Path for Colon Cancer with Peritoneal Metastasis | Naonao: Self-Rescue Journey After Recurrence of Colon Cancer at 27 | Sister Tudou: Seven-Year Anti-Cancer Journey for Colon Cancer with Lung and Brain Metastases | Jin Xia: Four-Year Treatment Path for HER2-Positive Gastric Cancer | Mickey: Late-Stage Gastric Cancer Treatment Path at 31 | Alison: Treatment for HER2-Positive Advanced Colon Cancer | From Stage IV Gastric Cancer to Complete Remission | 78 Liver Metastases Are Not a Death Sentence | The Late-Stage Cancer Patient Who Entered the ICU Due to Infection Is Now Tumor-Free | Anti-Cancer Blogger Fengzi Passes Away: Who Will Care for Young Patients Fighting Cancer Alone? | Sister Yangguang: Life Should Not Lose Its Color Due to Illness | Nine Years of Fighting Late-Stage Cancer: Happiness Still Found Me | From Postpartum Constipation to Late-Stage Colon Cancer: A Young Lynch Syndrome Mother's Anti-Cancer Miracle | A Post-85s Solo Anti-Cancer Journey: Unfinished and To Be Continued (Part 1)
Doctor-Patient Communication | Click text to jump
Peking University Cancer Hospital Shen Lin: Step-by-Step Guide for Colon and Gastric Cancer Patients on How to Seek Medical Care
Peking University Cancer Hospital Xing Baocai: Doctor-Patient Communication on Colon Cancer Liver Metastasis
Guangzhou Sun Yat-sen University Cancer Center Chen Gong: Can Surgery Be Performed Immediately After Colorectal Cancer Diagnosis? | On Surgery for Colorectal Peritoneal Metastasis | On Treatment Strategies for Colorectal Liver and Lung Metastasis
Guangzhou Zhongshan Sixth Hospital Xiao Jian: Chemotherapy, Targeted Therapy, and Immunotherapy for Advanced Gastric Cancer
Beijing Friendship Hospital Yao Hongwei: Examinations Rectal Cancer Patients Need and How to Read the Reports