When someone hears the word “cancer,” their mind usually jumps straight to survival rates and treatments. But for stomach cancer, there’s something equally important to ask first: What kind of stomach cancer is it?
Not all stomach cancers are the same. And knowing the type can make a world of difference when it comes to treatment, outcomes, and even symptoms. In this article, we’ll take a deep dive into adenocarcinoma, the most common type, and how it compares to other, lesser-known forms.
What Is Stomach Cancer?
Stomach cancer, also known as gastric cancer, occurs when abnormal cells in the lining of the stomach begin to grow uncontrollably. Over time, these cells can form a tumour, spread into nearby tissues, or even travel to distant parts of the body.
But here’s the thing: stomach cancer isn’t just one disease. It’s an umbrella term that covers several distinct types, each with its own behaviour, appearance under a microscope, and preferred treatments.
Why Understanding the Types Matters
Imagine you’re a tailor sewing a suit. Would you use the same fabric and measurements for every person? Of course not. It’s the same with stomach cancer. Different types behave differently.
- Some grow slowly.
- Others are aggressive and hard to control.
- Some respond well to chemo; others don’t.
So, knowing the exact type helps doctors pick the right tools—whether it’s surgery, chemo, or targeted therapy—and gives patients a clearer picture of what lies ahead.
Adenocarcinoma: The Most Common Type
Let’s start with the heavyweight: adenocarcinoma. This type makes up about 90-95% of all stomach cancers.
It starts in the glandular cells—the ones that produce mucus and stomach acid. Within this category, there are two subtypes:
- Intestinal type: tends to grow slower and is often linked to H. pylori infection.
- Diffuse type: more aggressive, tends to spread quickly, and harder to detect early.
Typical signs? Think bloating, nausea, loss of appetite, and unexplained weight loss. But here’s the catch: these symptoms can be pretty vague—easy to brush off as something minor. That’s why so many cases get caught late.
Lymphoma of the Stomach
Yes, lymphoma can happen in your stomach—not just in your lymph nodes. Known as gastric lymphoma, this type starts in the immune system cells located in the stomach wall.
The most common subtype? MALT lymphoma (mucosa-associated lymphoid tissue). It’s often linked to—you guessed it—H. pylori infection.
This cancer tends to grow slowly and may not need aggressive treatment right away. In fact, treating the infection itself can sometimes shrink the tumour.
Gastrointestinal Stromal Tumors (GISTs)
Ever heard of GISTs? If not, you’re not alone. These rare tumours arise from a special type of cell in the stomach wall called the interstitial cells of Cajal—basically, the stomach’s built-in pacemakers that help move food along.
Unlike adenocarcinomas, GISTs don’t respond well to traditional chemo. Instead, they’re often treated with targeted therapies like imatinib (Gleevec).
Symptoms can include:
- Stomach pain
- Vomiting blood
- Feeling full quickly after eating
Again, symptoms may seem ordinary—until they’re not.
Neuroendocrine Tumors (Carcinoid Tumors)
These slow-growing tumours come from cells that release hormones. While they sound exotic, they’re actually quite sneaky. Some don’t show any symptoms at all.
When they do, they may cause:
- Abdominal cramps
- Diarrhoea
- Skin flushing
Treatment depends on how far the cancer has spread, but surgery is often the first step. If the tumour is making too many hormones, patients may need medication to control those effects.
Less Common Types: Squamous Cell, Small Cell, and Others
Rare doesn’t mean impossible. A few stomach cancers don’t fit into the main categories:
- Squamous cell carcinoma: Begins in the flat cells that line some parts of the stomach.
- Small cell carcinoma: Highly aggressive, more common in the lungs but can appear in the stomach.
- Undifferentiated carcinoma: Cells are so abnormal that they don’t look like any normal stomach cells at all.
Because these are rare, there’s less research and fewer standard treatments. But they usually require a tailored, aggressive approach.
How Doctors Identify the Type of Stomach Cancer
So how do doctors figure out what type it is?
The process often starts with an endoscopy—a thin tube with a camera is used to view the inside of your stomach. During this, doctors collect a biopsy—a small tissue sample.
That tissue is then studied under a microscope. Special stains and genetic tests may be used to pinpoint the exact type. It’s not just about “is this cancer?” but “what kind of cancer is this?”
Do Symptoms Vary by Type?
Yes—and no.
Most stomach cancers share generic digestive symptoms like:
- Feeling bloated
- Heartburn
- Nausea
- Weight loss
But some types bring unique issues. For example, neuroendocrine tumours may affect hormone levels, while lymphomas might not show any symptoms at all until they’re quite advanced.
That’s why a thorough work-up is crucial, especially if symptoms persist beyond a few weeks.
Treatment Approaches Based on Cancer Type
No two patients are alike. And neither are stomach cancers. Here’s how treatment usually lines up by type:
- Adenocarcinoma: Surgery + chemo ± targeted therapy
- GISTs: Targeted drugs like imatinib
- Lymphoma: Antibiotics (for MALT), chemo or radiation (for aggressive types)
- Neuroendocrine tumours: Surgery + hormone therapy
- Rare types: Usually a combination of surgery, chemo, and experimental therapies
The goal? Personalised care that considers the biology of the tumour—not just its location.
Prognosis: Does the Type Affect Survival?
Absolutely.
Let’s look at a few rough figures (these vary by country and staging at diagnosis):
- Early-stage adenocarcinoma: 70–90% 5-year survival
- Late-stage adenocarcinoma: Less than 20%
- GISTs: Often excellent with targeted treatment
- MALT lymphoma: Very high survival rates if caught early
- Neuroendocrine: Depends on size and spread—can be years or months
So yes, type matters—a lot.
Can One Type Turn Into Another?
Good question.
While rare, it is possible for a tumour to evolve. For instance, a GIST may become more aggressive over time. Some adenocarcinomas can undergo changes that make them behave like a different subtype.
This is why ongoing monitoring is so important, even after treatment.
Conclusion: Knowing the Type Can Save Lives
Stomach cancer is not a one-size-fits-all disease. Whether it’s the common adenocarcinoma or a rare neuroendocrine tumour, knowing the type helps guide the journey ahead—medically, emotionally, and practically.
If you or someone you love is facing a stomach cancer diagnosis, don’t stop at “you have cancer.” Ask:
“What kind of stomach cancer is it?”
Because that question could change everything.
References
- Stomach Cancer Types – American Cancer Society (2023). https://www.cancer.org/cancer/stomach-cancer/about/what-is-stomach-cancer.html
- Gastrointestinal Stromal Tumors (GISTs) – National Cancer Institute (2022). https://www.cancer.gov/types/stomach/hp/gist-treatment-pdq
- Gastric Lymphoma – Cleveland Clinic (2023)
https://my.clevelandclinic.org/health/diseases/22136-gastric-lymphoma. Neuroendocrine Tumors of the Stomach – Cancer.Net (2023)
https://www.cancer.net/cancer-types/neuroendocrine-tumor - Gastric Cancer: A Comprehensive Review – Nature Reviews Disease Primers (2023). https://www.nature.com/articles/s41572-023-00464-4