The gallbladder is a small, pear-shaped organ located beneath the liver, responsible for storing bile, a digestive fluid produced by the liver that helps break down fats in food. Despite its relatively unassuming role, the gallbladder can be affected by various conditions, most commonly gallbladder stones and, in rare cases, gallbladder cancer.
Gallstone disease is common in Singapore, affecting 10–20% of the population. Conversely, gallbladder cancer is rare, accounting for less than 1% of gastrointestinal cancers. Importantly, these conditions can present with similar symptoms, underscoring the critical need for accurate diagnosis to ensure effective treatment.
What Are Gallstones?
Gallstones are solid masses formed by the hardening of bile components, mainly cholesterol or bilirubin, within the gallbladder or bile ducts. They can range in size and number, and while often asymptomatic, may obstruct bile flow, leading to sudden pain or complications like infection and inflammation.
Causes of Gallstones
Gallstones develop when there is a chemical imbalance in bile. The most common triggers include:
- Excess Cholesterol: When the liver secretes more cholesterol than bile can dissolve, the surplus crystallises into stones.
- High Bilirubin Levels: Conditions such as liver disease or blood disorders may cause excess bilirubin, encouraging pigment stone formation.
- Impaired Gallbladder Emptying: When bile stagnates due to reduced gallbladder contractions, it becomes concentrated and prone to crystallisation.
- Bile Microbiome Changes: Certain bacterial imbalances may increase the risk of stone formation.
Risk Factors for Gallstones
Multiple factors contribute to a person’s likelihood of developing gallstones:
- Biological Sex: Women are up to three times more prone to gallstones, partly due to oestrogen’s effect on bile cholesterol.
- Age: Risk increases after age 40, with older adults more likely to have asymptomatic stones.
- Body Weight: Obesity increases cholesterol levels in bile, while rapid weight loss can destabilise bile composition.
- Hormonal Factors: Pregnancy, hormone therapy, or birth control pills can all influence bile content.
- Diet and Lifestyle: Diets high in fat or refined carbs and low in fibre can disrupt bile composition.
- Medical Conditions: Diabetes, liver cirrhosis, Crohn’s disease, and certain blood disorders (e.g., sickle cell anaemia) increase risk.
What Is Gallbladder Cancer?
Gallbladder cancer is a rare but aggressive malignancy that begins in the lining of the gallbladder. Most cases originate in the innermost layer (mucosa) and spread outward. Due to its hidden location and vague early symptoms, it is often diagnosed late, when the cancer has already advanced beyond the gallbladder.
Causes of Gallbladder Cancer
Gallbladder cancer arises when normal cells mutate and begin to divide uncontrollably. These mutations are typically acquired over time, not inherited. While the exact cause of these changes remains unclear, chronic inflammation is believed to play a major role in damaging the gallbladder lining, setting the stage for cellular changes that can lead to cancer.
Risk Factors for Gallbladder Cancer
Several factors can elevate the risk of developing gallbladder cancer:
- Sex: Women are significantly more likely to be affected, likely due to hormonal influences like oestrogen, which can contribute to gallstone formation.
- Age: The risk rises after 65, with the average diagnosis occurring in the early 70s.
- Gallstones: Long-standing or large gallstones can cause chronic irritation, a known precursor to cancer.
- Gallbladder Polyps: Tissue growths, especially those larger than 1 cm, carry malignant potential.
- Primary Sclerosing Cholangitis: Ongoing inflammation of the bile ducts can increase cancer risk.
- Bile Duct Cysts (Choledochal Cysts): These congenital anomalies predispose the ducts to chronic inflammation and malignant transformation.
- Infections: Chronic Salmonella infections, including typhoid carriers, are linked to a higher incidence.
- Obesity: Excess weight increases the likelihood of gallstones and metabolic changes associated with gallbladder disease.
What Is the Difference Between Gallbladder Cancer and Gallstones?
Nature of the condition
- Gallbladder cancer: A cancerous condition that can be potentially life-threatening
- Gallstones: Benign, non-cancerous formations that are often harmless
Symptoms
- Gallbladder Cancer: Often silent early on, late symptoms include abdominal pain, jaundice, nausea, bloating, and weight loss.
- Gallstones: Can be asymptomatic; symptoms include upper right abdominal pain, jaundice, nausea, bloating, vomiting, and back pain between the shoulder blades.
Diagnosis
- Gallbladder Cancer: Imaging Tests, Biopsy, Post-surgery.
- Gallstones: Ultrasound, Imaging Tests, During routine exams.
Treatment
- Gallbladder Cancer: Gallbladder Surgery, Chemotherapy, Radiation (if operable).
- Gallstones: Usually managed by gallbladder removal (cholecystectomy).
Prognosis and Survival
- Gallbladder Cancer: Poor prognosis if diagnosed late; better if found early. Survival rate depends on the stage of the cancer.
- Gallstones: Excellent prognosis after treatment or surgery if symptomatic.
Can Gallstones Lead to Gallbladder Cancer?
Gallstones can increase the risk of gallbladder cancer, but it is important to understand that the relationship is complex and not causal in most cases. Gallstones are a recognised risk factor for gallbladder cancer, but most people with gallstones will never develop cancer.
When gallstones are present for a long time, especially larger ones (typically >3 cm), they may trigger a state of chronic cholecystitis, which damages the gallbladder’s inner lining. Over time, this constant irritation can lead to mutations in the cells, predisposing them to become cancerous.
However, this transformation is rare. While 70–90% of people with gallbladder cancer also have gallstones, only 1–3% of individuals with gallstones will ever develop gallbladder cancer in their lifetime. Most patients will live with gallstones without any malignant consequences.
Get Evaluated by a Gallbladder Doctor
Differentiating between gallstones and gallbladder cancer is vital for appropriate clinical decisions and treatment. Misinterpreting symptoms could delay cancer diagnosis, while overestimating cancer risk from gallstones may cause undue worry. If you experience gallbladder-related symptoms or need evaluation, consulting a gallbladder specialist is recommended.
Our gallbladder doctor, Dr Wong Jen San of the Hepatobiliary & Pancreatic Surgery Centre has extensive expertise in minimally invasive techniques and a strong academic background. He offers comprehensive and precise management of gallbladder conditions, from routine gallstones to complex gallbladder cancer.
Schedule an appointment with Dr Wong by contacting (65) 6235 4088 or emailing us at enquiry@liverpancreassurgery.sg.