Download Differential Diagnosis of an Anterior Mediastinal Mass

Approach to a Mass of Unknown
Significance
Location
Kinetics
Systemic Manifestations
Differential Diagnosis of an Anterior
Mediastinal Mass
Thymoma
Germ Cell Tumor/Teratoma
Lymphoma
Differential Diagnosis of an Anterior Mediastinal Mass
Shipp M et al. N Engl J Med 2005;352:1697-1704
Differential Diagnosis of an Anterior
Mediastinal Mass
Malignancy
Infection
Granulomatous Disease
Benign Tumors
Others
Our Patient
Familial Adenomatous Polyposis (FAP)
Autosomal Dominant Disease
High penetrance (almost ~100)
Mean age of onset 16
100-1,000s of colonic polyps
Average age of colon cancer is 39
Accounts for ~1% of all colorectal cancers
Genetics of FAP
•Classic FAP caused by mutation in APC
gene
•Accounts for 90% of cases
•Discovered at Johns Hopkins by Kenneth
Kinzler and Bert Vogelstein
•Genetic Test commercially available
FAP
Unaffected
Management of FAP
•Surveillance with annual colonoscopies
•Colectomy is recommended when polyps are large,
dysplastic or with villous histology
•Patients with small and/or sparse polyps can be followed
and schedule colectomy after graduation from High School
Total proctocolectomy with ileoanal pouch
Subtotal colectomy with ileorectoal anastomsosis
Classic Metastatic Colon Cancer to Lung
Extracolonic Malignancies in FAP patients
Malignancy
Absolute Lifetime Risk (%)
Colon
100
Duodenum
3.0–5.0
Thyroid
2.0
Brain (Meduloblastoma)
2.0
Ampullary
1.7
Pancreas
1.7
Hepatoblastoma
1.6
Gastric
0.6*
DESMOID TUMORS
Benign Slow Growing Tumors
Develop in 10-15% of patients with FAP
Typically intra-abdominal and arise at
sites of trauma (ie Surgery)
Composed of spindle cells and abundant
fibrous stroma
Final Differential Diagnosis
Atrial Myxoma
Indolent Lymphoma
Proliferative Fibrosing Mediastinitis
DIAGNOSIS
Desmoid Tumor arising in site of Surgical
trauma (CABG in 2002) in a patient with FAP