Breast biopsy system and methods

Abstract

An apparatus and method are provided for precisely isolating a target lesion in a patient's body tissue, resulting in a high likelihood of “clean” margins about the lesion when it is removed for diagnosis and/or therapy. This approach advantageously will often result in the ability to both diagnose and treat a malignant lesion with only a single percutaneous procedure, with no follow-up percutaneous or surgical procedure required, while minimizing the risk of migration of possibly cancerous cells from the lesion to surrounding tissue or the bloodstream. In particular, the apparatus comprises a biopsy instrument having a distal end adapted for entry into the patient's body, a longitudinal shaft, and a cutting element disposed along the shaft. The cutting element is actuatable between a radially retracted position and a radially extended position. Advantageously, the instrument is rotatable about its axis in the radially extended position to isolate a desired tissue specimen from surrounding tissue by defining a peripheral margin about the tissue specimen. Once the tissue specimen is isolated, it may be segmented by further manipulation of the cutting element, after which the tissue segments are preferably individually removed from the patient's body through a cannula or the like. Alternatively, the specimen may be encapsulated and removed as an intact piece.

1 . A biopsy instrument for retrieving body tissue, having a longitudinal axis and comprising: 
 distal end adapted for entry into a patient's body; and    a cutting element disposed on said instrument, said cutting element being actuatable between a radially retracted position and a radially extended position, relative to said axis, and being movable in said radially extended position to isolate a desired tissue specimen from surrounding tissue by defining a peripheral margin about said tissue specimen.    
   
   
       2 - 31  (Cancelled)  
   
   
       32 . The method as recited in  claim 40 , wherein said at least one encapsulating element comprises a plurality of bands which are disposed axially along said instrument.  
   
   
       33 . The method as recited in  claim 40 , and further comprising the step of proximally withdrawing said instrument, with the encapsulated tissue specimen, from the patient's body, said step including the step of cutting tissue as the instrument is withdrawn.  
   
   
       34 . The method as recited in  claim 40 , further comprising the step of segmenting s the tissue specimen.  
   
   
       35 . The method as recited in  claim 34 , further comprising withdrawing each segment of a the tissue specimen through a cannula lumen.  
   
   
       36 . The method as recited in  claim 34 , wherein the segmenting the tissue specimen includes the stop of radially retracting the cutting element so that the tissue specimen is segmented radially.  
   
   
       37 . The method as recited in  claim 34 , wherein the step of segmenting said tissue specimen includes the steps of partially radially retracting said cutting element from its fully radially expanded position and rotating the instrument about its axis to cut said tissue and create a circumferential tissue segment.  
   
   
       38 . The method as recited in  claim 37 , wherein the segmenting step is repeated at differing partially radially expanded positions of the cutting element, so that a plurality of circumferential tissue segments are created.  
   
   
       39 . The method as recited in  claim 40 , and further comprising the step of simultaneously moving the cutting element axially as it is rotated about said axis to cut said tissue.  
   
   
       40 . A method of cutting, isolating and removing a specimen of tissue from a site within a patient's breast, comprising: 
 a. providing an excisional device that includes a shaft, a cutting element coupled to the shaft which is movable from a retracted position to an expanded position and which is configured to cut the specimen from the breast tissue and at least one tissue collection element which is movable from a retracted configuration to an expanded configuration and which is configured to encapsulate at least part of the cut specimen;    b. introducing the excisional device into the patient's breast tissue with the at least one tissue collection element and the cutting element in retracted configurations;    c. expanding the cutting element to an expanded configuration after the excisional device is introduced into the patient's breast tissue and the cutting element is located at the site within the patient's breast;    d. moving the cutting element in the expanded configuration to cut the specimen from the patient's breast tissue at the site;    e. encapsulating at least part of the cut specimen with the at least one tissue collection element; and    f. removing the excisional device from the site while at least part of the specimen remains encapsulated within the at least one tissue collection element.    
   
   
       41 . The method of  claim 40 , wherein the cutting element is a flexible element which bows outwardly when moving to the expanded configuration.  
   
   
       42 . The method of  claim 40 , wherein the moving step includes rotating the cutting element about a longitudinal axis.  
   
   
       43 . The method of  claim 40 , wherein the moving step is carried out with the cutting element moving along an arcuate path.  
   
   
       44 . The method of  claim 42 , wherein the moving step includes moving the cutting element toward the retracted configuration after the specimen is cut.  
   
   
       45 . The method of  claim 40 , wherein the moving step is carried out with the cutting element being energized with RF energy.  
   
   
       46 . The method of  claim 40 , wherein the encapsulating step is carried out to physically isolate at least part of the tissue specimen from the surrounding tissue so that the specimen does not contact the surrounding tissue from which the specimen is cut.  
   
   
       47 . The method of  claim 40 , wherein the encapsulating step is carried out with the at least one tissue collection element expanding to a size at least as large as the tissue specimen.  
   
   
       48 . The method of  claim 40 , wherein the introducing step includes positioning the shaft so that the tissue cutting element is adjacent to the specimen to be cut.  
   
   
       49 . A method of cutting, isolating and removing a specimen of breast tissue, comprising: 
 a. providing an excisional device that includes a shaft, a cutting element coupled to the shaft and a tissue collection element, both the cutting element and the tissue collection element being movable from a retracted position to an expanded position, the cutting element being configured to cut the specimen from the breast tissue, the tissue collection element being configured to encapsulate the cut specimen;    b. introducing the excisional device into the breast tissue with the tissue collection and cutting elements both retracted;    c. expanding the cutting element to an expanded position after the introducing step;    d. moving the cutting element to cut the specimen from the breast tissue;    e. encapsulating the cut specimen with the tissue collection element, the tissue collection element being expanded to an expanded shape that is sufficiently large to enclose the specimen cut during the moving step; and    f. removing the excisional device while the specimen remains encapsulated within the tissue collection element.    
   
   
       50 . The method of  claim 49 , wherein the tissue collection element includes a flexible membrane and wherein the flexible membrane isolates the specimen from the breast tissue in the encapsulating step.  
   
   
       51 . The method of  claim 49 , wherein the cutting element is a flexible element which bows outward when moving to the expanded position and wherein the expanding step is carried out with the cutting element bowing outward.  
   
   
       52 . The method of  claim 49 , wherein the moving step includes rotating the shaft.  
   
   
       53 . The method of  claim 52 , wherein the moving step is carried out with the cutting element moving along an arcuate path.  
   
   
       54 . The method of  claim 56 , wherein the moving step is carried out by moving the cutting element toward the retracted position after the cutting element moves along the arcuate path.  
   
   
       55 . The method of  claim 52 , wherein at least some of the moving steps are carried out with the cutting element energized.  
   
   
       56 . The method of  claim 58 , wherein the cutting element is energized with RF energy.  
   
   
       57 . The method of  claim 52 , wherein the encapsulating step is carried out to physically isolate at least part of the tissue specimen from the surrounding tissue so that the tissue specimen does not contact the surrounding tissue from which the specimen is cut.  
   
   
       58 . The method of  claim 52 , wherein the introducing step includes positioning the shaft so that the cutting element is adjacent to the specimen to be cut.