(a) US- guided cryotherapy for local control. Left image, BC
performed with two cryoprobes (curved arrow) and a thermocouple (straight arrow)
for an irregular 2.0-cm mass using technique planning noted in Figure 1b for tumors closer to the chest wall. As this
was our second patient, this procedure also highlighted the need for better
circumferential posterior visualization of the iceball near the chest wall,
which was better provided with CT guidance. Middle image, Axial US image through
the largest portion of the irregular mass shows more posterior placements of
cryotherapy probes (curved arrows) and cross-section of a thermocouple en route
to the superior tumor (straight arrow). Despite the cancer being near the chest
wall, its medial location gave it a relatively superficial position for good US
visualization. Right image, sagittal US image shows the
posterior course of a thermocouple, which measured −57°C after
~8 minutes of the second freeze cycle at the superior tumor margin. The mobile
nature of this tumor allowed substantial retraction off the chest wall in
addition to saline injection. (b) MR images obtained before and
four weeks after cryotherapy for local control. Left image, axial T1-weighted MR
image obtained before cryotherapy at a similar tumor level as in Figure 2a. The
tumor is causing retraction but does not involve the skin. Right image, MR image
obtained four weeks after cryotherapy shows a low-signal-intensity rim of edema
(black arrows) surrounding an ovoid zone of avascular necrosis that extended
approximately 1 cm beyond all visible tumor margins but without extension into
the chest wall. The wheelchair-bound patient, who was not a candidate for
surgery, continued to do well with tumor involution of the primary and no
further progression of distant metastases on anastrozole (Arimidex; AstraZeneca
Pharmaceuticals, Delaware City, Delaware) alone until her death two years
later.