What Is the Spigelman Staging System for FAP Polyps?

When you have Familial Adenomatous Polyposis (FAP), your doctor will perform regular upper endoscopies to check your upper digestive tract for polyps. While they will look at your stomach, the severity of polyps in your duodenum (the first part of your small intestine) is measured using a specific scoring method called the Spigelman classification system ^[1][2].

It is important to know that the Spigelman stage is a tool to measure the risk of precancerous changes; it is not a cancer stage, and a high Spigelman stage does not mean you have cancer ^[3]. Stomach polyps are assessed separately and do not factor into this score ^[1]. Instead, your Spigelman stage helps your care team evaluate your risk for duodenal cancer over time, which helps guide how soon you need your next endoscopy or whether specialized treatments are needed ^[4].

How the Spigelman Score is Calculated

Your Spigelman score combines findings from two different reports: your endoscopy report (what the doctor saw during the procedure) and your pathology report (what the microscope showed from biopsies) ^[1]. Your doctor assigns 1 to 3 points across four categories ^[1]:

From your Endoscopy Report:

• Number of polyps: 1 to 4 polyps (1 point); 5 to 20 polyps (2 points); more than 20 polyps (3 points).
• Polyp size: 1 to 4 mm (1 point); 5 to 10 mm (2 points); larger than 10 mm (3 points) ^[5].

From your Pathology Report:

• Histology (Growth pattern): Tubular (1 point); Tubulovillous (2 points); Villous (3 points) ^[5].
• Dysplasia (How abnormal the cells look): Low-grade (1 point); High-grade (3 points). High-grade dysplasia means the cells look significantly abnormal (precancerous), though this is still not invasive cancer ^[5].

(Note: If zero polyps are found, your score is 0).

These points are added together for a total score of 0 to 12. This score directly corresponds to your Spigelman stage ^[1]:

What the Stages Mean for Your Care

Your Spigelman stage helps guide your surveillance plan ^[1]. Guidelines and individual patient risks vary, so the exact timing of your next endoscopy depends on your overall health, symptoms, and previous treatments. However, typical intervals are ^[4]:

• Stage 0 or I: Surveillance endoscopy typically every 4 to 5 years ^[4].
• Stage II: Surveillance endoscopy typically every 3 years ^[4].
• Stage III: Surveillance typically every 1 to 2 years (or 6 to 12 months, depending on specific findings like polyp growth or high-grade dysplasia) ^[4].
• Stage IV: This stage indicates a high burden of precancerous polyps. Surveillance is typically required every 6 months ^[4]. At this stage, you should be evaluated by a multidisciplinary team at an expert FAP center ^[6]. Advanced endoscopists may use specialized techniques to remove or destroy polyps, which can sometimes reduce your score ^[7]. If the polyps are growing rapidly, contain high-grade dysplasia, or cannot be safely managed with an endoscope, your care team will discuss risk-reducing surgery to remove part of the duodenum ^[8][9].

An Important Missing Piece: The Ampulla

The Spigelman stage has one major limitation: it does not specifically score the ampulla of Vater (the small opening where bile and pancreatic fluids enter the duodenum) ^[4].

Research shows that a substantial and highly variable proportion of FAP-related upper intestinal cancers occur at or near the ampulla, meaning a Spigelman Stage IV alone does not capture all cancer risk ^[3][4]. Because standard endoscopes look straight ahead, your doctor may need to use a special side-viewing scope to properly assess the ampulla ^[4]. If you have ampullary polyps, you should ideally be evaluated at an FAP center, as these lesions require separate, careful management ^[6].

When to Contact Your Doctor

Many people with duodenal polyps have no physical symptoms, which is why sticking to your scheduled surveillance is so important even when you feel well ^[4]. However, do not wait for your next scheduled endoscopy if you develop concerning signs. Contact your doctor immediately or seek urgent care if you experience ^[4]:

• Black, tarry, or bloody stools
• Persistent vomiting or the inability to keep fluids down
• Yellowing of your skin or eyes (jaundice)
• Severe or rapidly worsening abdominal pain
• Unexplained weight loss, fainting, or extreme weakness