This case demonstrates the full spectrum of imaging findings of a superior sulcus tumor (Pancoast tumor). After the initial core biopsy, the patient underwent 6 months of chemoradiotherapy in an attempt to downstage the tumor, as it was clearly involving the brachial plexus. 

Although post-treatment (pre-resection) MRI continued to suggest involvement of the brachial plexus, a PET scan (not-shown) failed to show any uptake, and an en-block resection was performed, which fortunately also did not demonstrate any viable tumor. This patient is currently being followed up as an outpatient. 

This is a good example of how difficult it is for non-functional imaging to distinguish viable from non-viable residual tumor. 

En-bloc resection pathology

MACROSCOPIC DESCRIPTION: A lung wedge with attached chest wall including two ribs and muscles.  The lung wedge, 100x35x45mm, contains a stapled surgical margin 130mm long.  

Slicing shows a softened area next to the pleura measuring 25x15mm.  No invasion is seen into the ribs.  The lung parenchyma shows no discrete parenchymal lesions.  Distance from margins: Medial soft tissue 3mm, lateral soft tissue 25mm, anterior soft tissue 15mm, posterior lung staple margin 30mm.

MICROSCOPIC DESCRIPTION: The biopsy contains nerve bundles, which are surrounded by fibrous tissue.  No tumor is identified. The sections contain variable amounts of blood vessels, nerve fibers and fibrofatty connective tissue.  They show no tumor involvement.

The sections contain lung parenchyma and attached chest wall.  All the macroscopically abnormal tissue has been submitted. There is a large area of necrosis in the chest wall which is abutting the pleura. It contains focal mucin pools and dystrophic calcification.  No viable tumor is identified.  The adjacent lung shows no tumor.  There is non-specific subpleural fibrosis.  Lymphovascular or perineural invasion is not seen.  The soft tissue and bony margins are unremarkable.

Sections of the completion lobectomy show no tumor.  The bronchial resection margin is clear.  There are four peribronchial lymph nodes with no tumor involvement.  The lung parenchyma is unremarkable.

DIAGNOSIS:

1. T1 nerve root, T2 pleura, inferior surface 1st rib, T1 root proximal, superior, inferior: No tumor identified.
2. Chest wall: Large area of necrosis in the chest wall, consistent with pre-operative chemoradiation effect.
   • Necrosis 25mm in size.
   • No viable tumor identified (complete response).
   • No evidence of lymphovascular invasion.
   • All soft tissue and bony margins clear.
3. Left upper lobectomy: No tumor identified.
   • Bronchial margin unremarkable.
   • 4 peribronchial lymph nodes present with no evidence of tumor.