Approach to a Mass of Unknown Significance

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Approach to a Mass of Unknown Significance

• Location
• Kinetics
• Systemic Manifestations

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Differential Diagnosis of an Anterior Mediastinal
Mass
Thymoma Germ Cell Tumor/Teratoma Lymphoma
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Differential Diagnosis of an Anterior Mediastinal
Mass
Shipp M et al. N Engl J Med 20053521697-1704
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Differential Diagnosis of an Anterior Mediastinal
Mass
Malignancy Infection Granulomatous
Disease Benign Tumors Others
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Our Patient
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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
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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

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FAP Unaffected
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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

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Classic Metastatic Colon Cancer to Lung
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Extracolonic Malignancies in FAP patients
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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
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Final Differential Diagnosis
Atrial Myxoma Indolent Lymphoma Proliferative
Fibrosing Mediastinitis
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DIAGNOSIS
Desmoid Tumor arising in site of Surgical trauma
(CABG in 2002) in a patient with FAP