An Approach to Abdominal Masses
Summary
This article attempts to summarize the approach to an abdominal mass.
Basics
An abdominal mass is defined as any kind of mass that lies in the abdomen, defined by the following borders:
- Posterior Border: The paraspinal muscles
- Superior Border: The costal margin
- Inferior Border: iliac crest AND public symphysis
- Anterior Border: Includes the anterior-lateral abdominal wall
Often, we are not sure of the origin of the abdominal mass. However, a thorough history and physical examination may give you some ideas about the location of the mass.
It is worth noting that the age of the patient may assist with several differentials, with elderly patients being at higher risk of developing malignancies. If the patient has a family history of malignancies then one should also keep this in mind. On history, one should ask the patient for details about the mass: onset, duration (chronic duration may be due to malignancy), rate of growth, location, history of trauma, and so forth. Associated symptoms are significant when approaching an abdominal mass. The following are some important associated symptoms:
History
It is worth noting that the age of the patient may assist with several differentials, with elderly patients being at higher risk of developing malignancies. If the patient has a family history of malignancies then one should also keep this in mind. You should ask the patient for details about the mass: onset, duration (chronic duration may be due to malignancy), rate of growth, location, history of trauma, and so forth. Associated symptoms are significant when approaching an abdominal mass. The following are some important associated symptoms:
- Pain: Explore the pain using the mnemonics SOCRATES/OLDCARTS
- Compressive Symptoms:
- Bowel Obstructive Symptoms: Vomiting, abdominal distension, constipation, obstipation, early satiety
- Biliary Obstructive Symptoms: Yellow discoloration of the skin and eyes, darkening colour of the urine, pale stools, itchy skin
- Neurovascular Symptoms: Remember that an abdominal mass may compress any vascular structure resulting in symptoms similar to those in peripheral vascular disease:
- Arterial: Claudication, cold lower limbs, painful lower limbs, tissue loss of the lower limbs
- Venous: Swelling of the lower limbs, congested superficial veins of the lower limbs
- Urinary Symptoms: Increased frequency of urination, difficulty with urinating
- Constitutional Symptoms: Loss of weight, loss of appetite, generalized body weakness
- Infectious Symptoms: Fever and night sweats may suggest TB. However, some patients with malignancies may develop fever as well (lymphoma).
- Bleeding: If the patient is vomiting, one should find out if there is blood in the vomit for stomach cancers and per rectal bleeding for colorectal malignancies.
- If Female: Per vaginal bleeding or discharge may provide information such as uterine fibroids, ca cervix, complicated pelvic inflammatory disease, and other gynecological malignancies.
- Metastatic Symptoms: Some of the symptoms from the compressive symptoms may be related to metastasis. However, try to think of the following three organs as well: bone, lungs, and brain. One should find out if the patient has any bone pain, respiratory symptoms (coughing/shortness of breath), or neurological symptoms (headaches, seizures, loss of conscience, changes in motor/sensations).
Physical Examination
On the physical examination, one should differentiate the patient that is “acutely-ill” looking vs “chronically-ill” looking. One should note in the general examination whether the patient has pallor (anemia), jaundice, dehydration, clubbing, edema, lymphadenopathy, and wasting to name a few. Each finding has an important clinical significance. For instance, pallor may suggest anemia which could be due to anemia of chronic disease or anemia of iron deficiency. While jaundice may suggest that the hepato-biliary system has been involved. Lymphadenopathy is very important, two “common” lymph node groups to assess are Sister Mary Joseph’s nodule/sign (malignant metastatic umbilical nodule) and Virchow’s node. Once there is a palpable, left supraclavicular lymph node (Virchow’s node) then one refers to this finding as Troisier’s sign. Other signs that are always important to look out for are the signs of chronic liver disease, liver failure, and portal hypertension.
When examining the abdomen, one should follow the standard method of examination: Inspection, Palpation, Percussion and Auscultation. On inspection, the abdomen may be distended, and usually, this distension is caused by the 5Fs: Fat, Fluid (Ascites), Flatus, Faeces, and Fatal Growth (Malignancies). However, regarding abdominal mass, there are several characteristics of an abdominal mass. These characteristics are the following:
- Skin changes: Are there any skin changes over the mass, such as ulceration, discoloration, scars, or hair distribution. For instance, a scar over an abdominal mass that protrudes when the patient coughs may be an incisional hernia.
- Location of the mass: The abdomen may be divided into 4 quadrants or into 9 regions. The location should be described accordingly, for instance, “An abdominal mass located on the right upper quadrant”.
- Size of the mass: The mass should be measured with a tape measure, for instance, “The mass was 4 by 8 cm in size”.
- Shape of the mass
- Consistency of the mass: Solid (solid organ, tumours), soft (bowel), fluctuant (abscess), cystic
- Surface of the mass: Irregular (more likely to be a malignancy), smooth, nodular (in the cirrhotic liver)
- Borders of the mass: Are the borders well defined or ill-defined.
- Tender or Non-Tender
- Movable/Ballotable/Pulsatile or fixed: A pulsatile mass always raises suspicion for a vascular structure such as an abdominal aortic aneurysm.
- Shifts with respiration
- Can you get above/below the mass: This will give you some idea about where the mass may be arising from. For instance, a pelvic mass may allow the examiner to get above the mass but not below the mass since it is a pelvic structure.
- Dullness of the mass: Percuss over the mass and listen for dullness. If the sound is tympanic it probably means that there may be bowel loops between the abdominal wall and the mass itself. This suggests that the mass may be from a retroperitoneal origin.
- Bruits: Auscultate the mass. For instance, a hernia with bowel as its content may have bowel sounds.
- Associated findings: Ascites (fluid thrill, shifting dullness), on rectal examination you may find signs suggestive of advanced carcinoma such as Blumer’s shelf sign. Therefore, it is important to state in this part that the abdominal examination should always include a rectal examination to assess for bleeding, masses, colour of stool (pale in obstructive jaundice, bloody ), and so forth.
There are many other findings that are not mentioned above for the sake of simplicity, but a full systematic examination is required. One common question is how do we differentiate an abdominal mass that arises from inside the abdomen from a mass that arises from the abdominal wall. The Valsalva Maneuver may help differentiate this mass because it will often “hide away” an intrabdominal mass since the abdominal muscles become contracted.
Differentials
One may use a mnemonic that is very useful for differentials known as “MINT”. This stands for Malformation, Inflammation, Neoplasm, and Trauma. Then one thinks about the location of the mass and the structures that are found in the same region. For instance, for a mass on the right upper quadrant, the liver may have several differentials such as:
- Malformation: Cyst
- Inflammation: Abscess
- Neoplasm: Carcinoma
- Trauma: Contusion, Laceration
Below, we will briefly share some common differentials. However, always remember that some abdominal masses can occur throughout the abdomen such as skin (cysts, abscesses, carcinoma of the skin) and hernias, fecal impaction, and lipomas.
Right Upper Quadrant
-Abscess, Subphernic Abcess -Hepatitis -Carcinoma -other causes of hepatomegaly. -Cholecystitis/Cholelithiasis -Cholangioma/Cholangiocarcinoma -Carcinoma of the head of pancreas -Pseudocyst -Hydronephrosis -Polycystic kidneys -Wilms tumour -Pheochromocytoma -Adrenal carcinoma |
Epigastrium
-Hypertrophic Pyloric Stenosis -Pseudocyst -Abscess, Subphernic Abcess -Hepatitis -Carcinoma - other causes of hepatomegaly -intussusception |
Left Upper Quadrant
-Tumours -Hydronephrosis -Polycystic kidneys -Wilms tumour -Pheochromocytoma -Adrenal carcinoma |
Right Lower Quadrant
-Intussusception -Carcinoma -Parasites -Colitis - appendix (appendicular abscess, phlegmon) -Tubo-ovarian abscess |
Hypogastrium
|
Left Lower Quadrant
-Carcinoma -Colitis - appendix (appendiceal abscess, phlegmon) -Tubo-ovarian abscess |
You may have noticed two things in this table:
|
||
Investigations
- Bloods:
- FBC – Anemia, Infection
- The patient may need an anemia work-up
- The patient may also need a septic screen, depending on the differentials
- Urea and Electrolyte – Electrolyte imbalance, renal function
- Liver function tests
- Low albumin: Seen in malnourished states
- Raised: Bilirubin: If conjugated more than unconjugated, usually seen in obstructive jaundice.
- Raised ALP AND GGT: Usually seen in biliary pathology.
- Raised AST AND ALT: Usually seen in hepatocellular pathology
- Tumour Markers: AFP (Hepatocellular carcinoma, Germ Cell Tumours), CA 19-9 (Pancreatic carcinoma and other GIT malignancies), CA-125 (Ovarian malignancies)
- FBC – Anemia, Infection
- Imaging
- X-Rays
- Erect Chest X-Ray: Cannonball lesions from metastasis, malignant effusions, rule out air under the diaphragm
- Abdominal X-Ray Erect AND Supine: This is important to visualize signs suggestive of a bowel obstruction.
- Ultrasound
- Ultrasound is non-invasive however it is very user dependent. It helps with finding out the source of the mass, the consistency of the mass, and other associated findings of the mass. An abdominal ultrasound may also help you assess the status of the hepatobiliary tree and assess the degree of ascites.
- Abdominal CT Scan
- This investigation is much more sensitive and specific than an ultrasound. A CT scan will provide much more detail regarding the mass and it will assist with the planning of further management (surgery) of the patient. A staging CT Scan will also be needed if a malignancy is confirmed.
- X-Rays
- Biopsy
- The mass should be biopsied, especially if a malignancy is suspected. This will provide a histological diagnosis. There are several methods of performing a biopsy: Fine Needle Aspiration, Tru-cut biopsy, Image Guided Biopsy, and Endoscopic biopsies. There are some masses that one should avoid performing a biopsy, this usually includes masses that are highly vascularized or masses that arise from a vascular structure.
Treatment
The treatment depends on the type of mass found.
Made with ❤️ by QuickBeat
We are a small education agency that aims to provide medical education.
EXPLORE
SERVICES
CONTACT
- Pretoria North, Gauteng
- contact@quickbeat.co.za