Learn about new colon cancer treatment approaches

Learn about new colon cancer treatment approaches

living, but nothing hits quite like hearing that from someone you love. That phone call is why I’ve been obsessively tracking new colon cancer treatments for the last few years—and why I recently dove deep into what’s actually changing the game.

I’m not a doctor, but I spend a big chunk of my week reading clinical trial data, oncology conference notes, and pestering specialists for explanations in plain language. What I’ve found is honestly more hopeful than I expected: colon cancer treatment is going through a quiet revolution.

Let me walk you through what I’ve learned, what I’ve seen work, and where the hype doesn’t match reality.

From “one-size-fits-all” to precision treatment

When my uncle was treated for colon cancer over a decade ago, the approach was brutally simple: surgery if possible, then chemotherapy like FOLFOX or FOLFIRI, maybe some radiation depending on location. There wasn’t much tailoring.

Now? Oncologists talk about molecular profiling, MSI status, RAS mutations, and HER2 amplifications before they even finalize a treatment plan.

The genetic fingerprint of your tumor

I recently sat in on a tumor board meeting at a university hospital (one perk of my job), and I watched a group of oncologists pull up a patient’s next-generation sequencing (NGS) report like it was a Google Doc. They weren’t just saying “stage III colon cancer.” They were asking:

• Is this tumor MSI-high (microsatellite instability-high) or MMR-deficient (dMMR)?
• Does it have a KRAS or NRAS mutation?
• Any BRAF V600E mutation?
• Is it HER2-positive?

These details now guide whether a patient might benefit from immunotherapy, targeted therapy, or a specific chemo combo. That’s a huge shift.

• More personalized treatment
• Better chance of hitting the tumor’s specific weakness
• Sometimes fewer side effects than “carpet bombing” chemo

• Not all hospitals run full molecular panels
• Insurance coverage can be patchy
• Even with profiling, some tumors don’t have any obvious “target”

Immunotherapy: when the immune system becomes the treatment

Immunotherapy sounded like sci-fi to me the first time I heard about it—“we’ll teach your immune system to see the cancer and fight it.” Then I started reading patient stories and trial data, and it got very real.

The biggest breakthrough in colon cancer so far is in people whose tumors are MSI-high or dMMR (about 10–15% of cases, more in early-stage, less in metastatic).

Checkpoint inhibitors

These drugs basically take the brakes off your immune system so it can attack the tumor.

The big names:

• Pembrolizumab (Keytruda) – anti–PD-1
• Nivolumab (Opdivo) – anti–PD-1
• Nivolumab + ipilimumab (Yervoy) – PD-1 + CTLA-4 combo

When I dug into the KEYNOTE-177 trial (presented 2020), I was honestly stunned. For metastatic MSI-high colon cancer:

• Pembrolizumab doubled progression-free survival compared with standard chemo (16.5 months vs 8.2 months)
• Fewer severe side effects than chemo

When I asked an oncologist about it, she said, “For the right patients, this has completely changed the first-line treatment algorithm.”

In my experience reading patient forums, you’ll see stories like: “They told me I had stage IV and I was terrified, then they found out I was MSI-high and I started immunotherapy—and my scans started shrinking in months.” Not everyone gets a miracle response, but some do.

• Only works well in a minority (MSI-high/dMMR) of colon cancers
• Immune-related side effects can be serious: colitis, thyroid problems, hepatitis, even rare life-threatening reactions
• It’s expensive, and access varies by country and insurance

But if you or a loved one is dealing with colon cancer and no one has mentioned MSI or MMR testing yet—that’s a conversation to push for.

Targeted therapies: going after specific weak points

When I tested my understanding of targeted therapy with a GI oncologist, he explained it this way: “Chemo attacks fast-growing cells. Targeted therapy attacks specific abnormal signals the cancer uses to grow.” That clicked for me.

Here are a few of the big players in colon cancer right now.

Anti-EGFR therapy (for RAS wild-type tumors)

Some colon cancers are RAS wild-type (no KRAS or NRAS mutation) and rely heavily on the EGFR pathway to grow.

• Cetuximab (Erbitux)
• Panitumumab (Vectibix)

These antibodies block EGFR and can be very effective—but only if the tumor is RAS wild-type. If there’s a KRAS or NRAS mutation, they basically don’t work. That’s why RAS testing is now standard.

What I’ve seen:

• Oncologists often combine these drugs with chemo in metastatic disease
• Some patients see impressive tumor shrinkage, especially with left-sided colon tumors

The catch? Skin toxicity. I’ve interviewed multiple patients who said, “The rash was honestly worse than the hair loss.” It can look like severe acne, affect nails, and be socially and physically painful. But there are decent skincare protocols that help if started early.

BRAF-targeted therapy

For tumors with BRAF V600E mutations (about 8–10% of colon cancers), prognosis used to be particularly poor. Then came combinations like:

• Encorafenib (BRAF inhibitor) + cetuximab (EGFR inhibitor)

The BEACON CRC trial showed improved overall survival with this combo compared with standard chemo for BRAF V600E metastatic disease. It’s not a cure-all, but it’s a much better option than we had ten years ago.

HER2-targeted therapy

A smaller subset of colon cancers are HER2-positive. Historically, they didn’t respond to standard anti-EGFR drugs.

Now we’re seeing:

• Trastuzumab + pertuzumab
• Trastuzumab deruxtecan (Enhertu) in trials

I recently read a 2023 case series where patients with HER2-positive metastatic colon cancer who’d failed multiple lines of treatment still responded to HER2-targeted combinations. We’re talking meaningful tumor shrinkage and more months of stable disease.

New angles on chemotherapy and surgery

Chemotherapy hasn’t gone away—it’s evolving.

Smarter chemo, not just more chemo

Regimens like FOLFOX (5-FU, leucovorin, oxaliplatin) and FOLFIRI (5-FU, leucovorin, irinotecan) are still the backbone. But:

• Dosing is better tailored to body surface area and tolerance
• Neuropathy monitoring with oxaliplatin is more proactive; some centers are quicker to adjust or stop the drug
• Combinations with targeted drugs (like bevacizumab or cetuximab) are used based on tumor profile

One colorectal surgeon told me, “We’re using chemo to convert some stage IV patients into surgical candidates. That was rare 20 years ago; now it’s a genuine goal in selected cases.”

HIPEC and more aggressive local approaches

For certain patients with colon cancer that’s spread to the peritoneum (the lining of the abdomen), there’s a technique called cytoreductive surgery with HIPEC (hyperthermic intraperitoneal chemotherapy).

In plain English: surgeons remove as much visible tumor as possible, then bathe the abdomen in heated chemo. It’s intense, long surgery with serious recovery.

What I’ve heard from specialists:

• It can extend survival significantly for carefully selected patients
• It’s not a match for everyone (age, overall health, extent of disease matter a lot)
• The data is still mixed, and different centers have different protocols

If someone mentions HIPEC, that’s a sign you should be at a high-volume center with real experience in this exact procedure.

Clinical trials: where tomorrow’s standard treatments are hiding

Whenever I talk to patients who are open to it, I nudge them to at least look at clinical trials. Not as a last resort, but as a parallel path.

I’ve seen trials exploring:

• Combination immunotherapies for MSI-high and even MSS (microsatellite stable) tumors
• Cancer vaccines aimed at preventing recurrence after surgery
• Circulating tumor DNA (ctDNA)–guided treatment, where blood tests detect microscopic residual disease and guide chemo intensity

The ctDNA space especially fascinates me. I read a 2022 study where ctDNA-positive patients after surgery had a sky-high risk of recurrence, while ctDNA-negative patients did much better. Trials are testing whether we can safely reduce chemo in ctDNA-negative patients and escalate in ctDNA-positive ones.

The honest downside: clinical trials can mean extra visits, travel, and more uncertainty. And not every promising early result pans out. But many of the treatments I’ve just described—pembrolizumab, encorafenib + cetuximab—came from patients who said yes to trials a few years ago.

Where hope is real—and where it’s overhyped

After tracking this space and talking to both patients and clinicians, here’s my straight-up take:

• If your tumor is MSI-high/dMMR, immunotherapy has dramatically changed the outlook
• If you have actionable mutations (RAS wild-type, BRAF V600E, HER2-positive), targeted therapy can meaningfully extend and improve life in advanced disease
• For earlier stages, better surgery plus smarter use of chemo is steadily improving survival

• Social media “miracle cures” (special diets, supplements, ozone therapy, etc.) claiming to replace medical treatment—none of these have strong evidence on par with what I’ve described above
• Anyone promising 100% cure for metastatic colon cancer with unproven methods
• Clinics asking for huge out-of-pocket payments for experimental treatments that aren’t in regulated trials

I recently saw a patient story in a Facebook group where someone stopped chemo in favor of a supplement-heavy alternative protocol. Six months later, their scans were much worse and they had fewer options left. That kind of thing makes me furious, because there are real innovations worth fighting for—but they live in solid science, not miracle marketing.

Questions to ask your doctor (or your loved one’s doctor)

If I were sitting next to you in a waiting room, this is the list I’d scribble on a notepad:

1. Has my tumor been tested for MSI/MMR status, RAS, BRAF, and HER2?
2. Am I a candidate for immunotherapy or targeted therapy based on those results?
3. Is surgery an option now—or could chemo/shrinking the tumor make surgery possible later?
4. Are there clinical trials I should at least look at, locally or at nearby centers?
5. How will you help manage side effects like neuropathy, rash, fatigue, or bowel changes?
6. How often will we re-scan and re-evaluate the plan?

You don’t have to memorize all the terminology. Just asking these questions signals, “I’m engaged. I want the most current, evidence-based options.” And that alone can change the tone of the conversation.

Colon cancer is still a serious, sometimes brutal disease. I won’t sugarcoat that. But compared with what my uncle faced, the landscape now is almost unrecognizable—in the best way. We’re not at the finish line, but we’re no longer running blind.

And if you’re reading this for yourself or someone you care about: you’re already doing the hard, unglamorous work that actually changes outcomes—getting informed, asking better questions, and refusing to settle for outdated assumptions.

Sources

• MSKCC: Immunotherapy for Colorectal Cancer - Overview of immunotherapy options and who they help
• KEYNOTE-177 Trial – NEJM - Pembrolizumab vs chemotherapy in MSI-high metastatic colorectal cancer
• National Cancer Institute – Colon and Rectal Cancer Treatment (PDQ) - Detailed, regularly updated treatment guidelines
• American Cancer Society – Targeted Therapy for Colorectal Cancer - Plain-language explainer of major targeted drugs
• MD Anderson – HIPEC for Colorectal Cancer - Explanation of HIPEC and which patients may benefit