Cryoablation system and method for treating breast tumor excision cavity margins with adaptive contact, tissue compression, and controlled cryogenic temperature delivery

A surgical cryoablation device for treating a marginal tissue region in a surgically created tissue cavity following excision of a breast tumor, the device comprising:

• a shaft;
• a fixed-shape, rigid probe element mounted on a distal region of the shaft, the probe element having an exterior heat transfer surface shaped and sized to make contact with an inner surface of the surgically created tissue cavity when placed therein, the probe element comprising a biocompatible material selected from the group consisting of stainless steel, cobalt-chrome alloy, titanium, nickel-titanium alloy, and combinations thereof;
• a cryogenic fluid supply conduit and a cryogenic fluid return conduit each coupled to the probe element, the cryogenic fluid supply conduit delivering a cryogenic fluid to circulate along the exterior heat transfer surface via the cryogenic fluid return conduit;
• at least one temperature sensing element configured to measure tissue temperature at a defined depth from the exterior heat transfer surface to confirm achievement of a lethal tissue temperature of −40° C. or lower at the target ablation depth;
• and
• a suction conduit positioned exterior to the probe element and in fluid communication with a vacuum source and configured to remove air or wound fluid between the exterior heat transfer surface and the tissue cavity to ensure intimate thermal contact between the probe element and the cavity wall.

A cryoablation system for treating a tissue cavity created by excision of a breast tumor, the system comprising:

• a cryoablation probe configured to make thermal contact with inner walls of the tissue cavity, the probe comprising at least one adaptive contact mechanism configured to conform the probe surface to an irregular geometry of the cavity walls;
• a tissue compression mechanism configured to apply a compressive force to tissue surrounding the cavity to eliminate interfacial air gaps, increase tissue density, and improve thermal conductivity at the probe-tissue interface;
• a console connected to the cryoablation probe by one or more fluid and electrical umbilicals, the console comprising a cryogenic fluid source, a control unit, and a display;
• and
• a temperature monitoring system comprising at least one temperature sensing element positioned to measure tissue temperature at a target ablation depth during cryoablation, the control unit being programmed to confirm achievement of a lethal tissue temperature of −40° C. or lower at the target ablation depth and to display a real-time graphical representation of isotherm progression from the probe surface through the surrounding tissue.

A method for treating tissue surrounding a surgically created cavity following excision of a soft tissue tumor in a breast, the method comprising:

• creating the cavity by removing at least a portion of a tumor;
• inserting a cryoablation probe comprising at least one adaptive contact mechanism into the cavity;
• deploying the at least one adaptive contact mechanism to conform the probe surface to the geometry of the cavity walls and establish substantially complete thermal contact between the probe surface and the cavity wall tissue;
• applying compressive force to tissue surrounding the cavity to eliminate interfacial air gaps and increase tissue density at the probe-tissue interface;
• and
• activating cryoablation to cool tissue surrounding the cavity to a lethal tissue temperature of −40° C. or lower at a target ablation depth of 0.5 to 2.0 cm from the inner surface of the cavity wall.