RADIOLOGICAL FINDINGS:

Barium Swallow (Esophagram): Annular constricting lesion of the esophagus at the level of the thoracic inlet to the level of the aortic arch (proximal esophagus).

   Chest CT: Soft tissue density mass in the superior mediastinum behind the trachea measuring 4.5 cm x 5 cm. Narrowing of the esophageal lumen. Subsequent images demonstrated no mediastinal or hilar lymphadenopathy or lung parenchymal abnormalities.


DIAGNOSIS: Squamous Cell Carcinoma of the Esophagus (Biopsy proven)

DIFERENTIAL DIAGNOSIS:
Leiomyosarcoma
Lymphoma
Mets

DISCUSSION:
Esophageal Carcinoma remains a disease of very high mortality that typically occurs in older adults. Accounting for 1% of all Gastrointestinal cancers, esophageal cancer has a 5% 5-year mortality rate. Commonly cited risk factors include: Head & Neck Cancer, Smoking, Alcohol, Achalasia and caustic ingestion for Squamous Cell Carcinomas (SCC) and Barrett’s Esophagus for Adenocarcinoma. With SCC accounting for 90-95% of esophageal cancers, and with adenocarcinomas virtually the remainder (5-10%), although rare other forms—lymphoma, leiomyosarcoma--can occur. Radiographically, biopsy proven esophageal cancer usually exhibits one of four patterns:

1) Annular Constricting (most common)-irregular ulcerated stricture
2) Polypoid - intraluminal filling defect
3) Infiltrative - growth through submucosa may simulate benignity
4) Ulcerated (least common)

Location of the tumor strongly suggests tumor type based on the following 3 regions:
Proximal & Mid Esophagus-Squamous Cell
Distal Esophagus: Adenocarcinoma.

CT remains the modality most commonly used and therefore CT Staging can aid with surgical planning:

   Stage I: Intraluminal Mass or localized wall thickening (3-5 mm). No adenopathy
   Stage II: Greater than 5 mm of esophageal wall thickening. No mets
   Stage III: Wall thickening with direct extension into adjacent mediastinum
   StageIV: Metastatic Disease

To accurately stage patients therefore certain radiographic findings are critical to look for. Since the tumor can spread by direct invasion, the radiologist must pay careful attention to the fat planes between adjacent structures (Aorta). Obliteration of these planes is suggestive of tumor invasion and plays critically in the preoperative assessment. Sinus tracts or fistulae between the tracheobronchial tree can also form. Investigation of the lung and liver parenchyma since hematogenous spread will often occur there. Lastly, lymphatic spread of tumor can cause pathologic lymphadenopathy of the mediastinal, hilar, or abdominal (gastrohepatic) lymph nodes.

Unfortunately, despite curative attempts at resection, survival remains dismal for this dreaded disease.


REFERENCES:
Eisenberg, R. Gastrointestinal Radiology: A Pattern Approach. Lippincott-Raven. 1996. pp369-372.

Brant, W. Fundamentals of Diagnostic Radiology. Lippincott Williams & Wilkins. 1999. pp718-719.

Slone, R., Pickhardt, P. Body CT A Practical Approach. McGraw-Hill. 2000. pp72-3.