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: 
 an elongated tubular shaft having a proximal end and a distal end adapted for entry into a patient's body; and    a cutting element disposed on elongated tubular shaft which is actuatable between a radially retracted position and a radially extended position, relative to the longitudinal axis, and which is rotatable in a radially extended position about the longitudinal axis to isolate a desired tissue specimen from surrounding tissue.    
   
   
       2 . The biopsy instrument as recited in  claim 1 , wherein the cutting element is rotatable about the longitudinal axis in radially extended position to isolate desired tissue specimen.  
   
   
       3 . The biopsy instrument as recited in  claim 1 , wherein said cutting element is movable axially in said radially extended position to isolate said desired tissue specimen.  
   
   
       4 . The biopsy instrument as recited in  claim 1 , said distal end comprising an electrosurgical cutting element for cutting tissue and facilitating advancement of said instrument into the patient's body.  
   
   
       5 . (Cancelled)  
   
   
       6 . The biopsy instrument as recited in  claim 1 , wherein the cutting element is an electrosurgical cutting element.  
   
   
       7 . The biopsy instrument as recited in  claim 6 , wherein the electrosurgical cutting element is a monopolar electrode.  
   
   
       8 . The biopsy instrument as recited in  claim 6 , wherein the electrosurgical cutting element is a bipolar electrode.  
   
   
       9 . The biopsy instrument as recited in  claim 8 , wherein a portion of said shaft has a return bipolar electrode.  
   
   
       10 . The biopsy instrument as recited in  claim 1 , including a sheath which is axially movable between distal and proximal positions for selectively covering and uncovering the cutting element.  
   
   
       11 . The biopsy instrument as recited in  1 , including a proximal driver unit for controlling radial expansion and retraction of the cutting element rotation.  
   
   
       12 . The biopsy instrument as recited in  claim 1 , wherein a proximal driver unit for controlling axial movement of the shaft sheath.  
   
   
       13 . The biopsy instrument as recited in  claim 1 , wherein the cutting element is configured to segment the tissue specimen after it has been isolated from the surrounding tissue.  
   
   
       14 . The biopsy instrument as recited in  claim 1 , wherein the cutting element is configured to segment the tissue specimen as the cutting element is retracted from the radially extended position to the radially retracted position.  
   
   
       15 . The biopsy instrument as recited in  claim 14 , wherein the cutting element is configured to be rotatable about the axis from a plurality of radially extended positions to selectively peripherally segment the tissue.  
   
   
       16 . The biopsy instrument as recited in  claim 13 , including a cannula having a lumen for removing one or more segments of the tissue specimen from the patient's body.  
   
   
       17 . The biopsy instrument as recited in  claim 1 , including a tissue collection component for encapsulating the tissue.  
   
   
       18 . The biopsy instrument as recited in  claim 17 , wherein the tissue collection component is a band which is disposed along said shaft and which is actuatable between a radially retracted position and a radially extended position.  
   
   
       19 . The biopsy instrument as recited in  claim 17 , wherein the tissue collection component is a plurality of bands which are disposed along the shaft and which are actuatable between radially retracted positions and radially extended positions.  
   
   
       20 - 28 . (Cancelled)  
   
   
       29 . A method for severing a tissue specimen from a tissue site within a patient's body and retrieving the severed tissue specimen from a the tissue site, comprising: 
 a. providing an elongated biopsy device having a distal end, a longitudinal axis, and an axially disposed cutting element;    b. advancing the elongated biopsy device into the patient's body, so that the distal end is disposed in the tissue site from which the tissue specimen is to be taken;    c. bowing the cutting element radially outwardly from the longitudinal axis of the biopsy device;    d. rotating the cutting element about the longitudinal axis to sever the tissue specimen from the tissue site; and    e. collecting the tissue severed by the cutting element in a tissue collection device.    
   
   
       30 . The method as recited in  claim 29 , wherein the tissue specimen is collected by encapsulating the tissue specimen.  
   
   
       31 . The method as recited in  claim 30 , wherein the encapsulation includes radially expanding at least one encapsulating element so that a portion thereof is radially outwardly spaced from the axis of said instrument and rotating biopsy device about its longitudinal axis so that said at least one encapsulating element encloses the tissue specimen.  
   
   
       32 . The method as recited in  claim 31 , wherein said at least one encapsulating element comprises a plurality of bands which are disposed axially along said instrument.  
   
   
       33 . Cancelled  
   
   
       34 . The method as recited in  claim 29 , and further comprising the step of segmenting said tissue specimen.  
   
   
       35 . The method as recited in  claim 34 , and further comprising the step of withdrawing each segment of said tissue specimen through a cannula lumen.  
   
   
       36 . The method as recited in  claim 34 , wherein the step of segmenting said tissue specimen includes the step of radially retracting said 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 29 , and further comprising the step of simultaneously moving the cutting element axially as it is rotated about said axis to cut said tissue.  
   
   
       40 . The biopsy instrument of  claim 10  including a proximal driver unit for controlling the rotation of the cutting element about the longitudinal axis.  
   
   
       41 . The biopsy instrument of  claim 10  including a proximal driver unit for controlling axial movement of the sheath.  
   
   
       42 . The biopsy instrument of  claim 17 , wherein tissue collection component is configured to withdraw the specimen from the patient's body as a single unit.  
   
   
       43 . An instrument assembly for isolating a tissue specimen from an intracorporeal site, comprising: 
 a. an elongate shaft which has a longitudinal axis and a distal end;    b. an electrosurgical tissue cutting component which is radially extendable from a retracted position to an extended position and which is configured to electrosurgically isolate a desired tissue specimen from surrounding tissue at the site; and    c. a tissue collection component coupled to the shaft which is configured to encapsulate the isolated tissue specimen from the surrounding tissue at the site.    
   
   
       44 . The instrument assembly of  claim 43  wherein the tissue collection component is configured to maintain the encapsulated tissue specimen intact.  
   
   
       45 . The instrument assembly of  claim 43  wherein the tissue cutting component is longitudinally disposed on the elongate shaft proximal of the distal end of the shaft.  
   
   
       46 . The instrument assembly of  claim 43  wherein the tissue cutting component is configured to be rotated at least in part about the longitudinal axis in the radially extended position to isolate the tissue specimen.  
   
   
       47 . The instrument assembly of  claim 46  wherein both the cutting component and the tissue collection component are movable from a retracted position to an expanded position.  
   
   
       48 . An excisional device for cutting and removing a specimen of breast tissue, comprising: 
 a shaft;    a tissue cutting component coupled to the shaft and configured to cut the specimen of breast tissue from surrounding breast tissue;    a tissue collection component coupled to the shaft which is configured to encapsulate the cut specimen and maintain the encapsulated specimen intact, both the cutting component and the tissue collection component being movable from a retracted position to an expanded position.    
   
   
       49 . The instrument assembly of  claim 48  wherein at least one tissue collection component has a proximal end and a distal end and which is configured to move one end closer to the other end to effect radial extension from the retracted position to the radial extended arcuate position.  
   
   
       50 . The instrument assembly of  claim 48  wherein the tissue collection component is configured so that the distal end is fixed and the proximal end move toward the distal end.  
   
   
       51 . The instrument assembly of  claim 48 , wherein the tissue collection component and the tissue cutting component are configured to expand and retract together.  
   
   
       52 . An instrument for encapsulating and removing a tissue specimen from a patient's body, comprising: 
 a. an elongate shaft which has a distal end a longitudinal axis    b. a tissue cutting component which is disposed on a distal portion of the elongate shaft, which is radially extendable from a retracted position to an extended position, relative to the longitudinal axis, which has an arcuate shape in the extended position and which is movable in the radially extended position about the longitudinal axis to isolate a desired tissue specimen from surrounding tissue by defining a peripheral margin about said tissue specimen; and    c. an encapsulation component for encapsulating the tissue specimen after it has been isolated from surrounding tissue and removing it from the patient's body intact.    
   
   
       53 . The instrument of  claim 52  wherein the instrument has a distal tissue cutting element with a linear cutting surface disposed on the distal end of the shaft to facilitate accessing the tissue specimen within the patient's body.  
   
   
       54 . The instrument of  claim 52 , wherein the encapsulation component has a plurality of encapsulation elements which are radially extendable from a retracted position to an extended position.  
   
   
       55 . An excisional biopsy method for soft tissue: 
 a. inserting a generally tubular member into the tissue, the tubular member including a cutting tool adapted to selectively bow away from the tubular member and a tissue collection device near a distal tip of the tubular member;    b. rotating the cutting tool;    c. selectively varying a degree of bowing of the cutting tool away from the tubular member;    d. collecting tissue severed by the cutting tool in the tissue collection device; and    e. retracting the tubular member from the soft tissue.    
   
   
       56 . The method of  claim 55 , further comprising the step of controlling the cutting tool to assume a non-extended state prior to the inserting step and before the retraction step.  
   
   
       57 . The method of  claim 55 , wherein the extension of the cutting tool is controlled by pushing and retracting a proximal end of the cutting tool in the distal and proximal directions, respectively.