A system for removal of a tissue specimen from an internal body cavity, comprising: a cannula arrangement, including: an access cannula including a first elongated tubular member defining a first lumen extending therethrough; a deployment cannula including a second elongated tubular member defining a second lumen extending therethrough and configured for insertion into the first lumen, the second elongated tubular member defining a diameter less than a diameter of the first elongate tubular member such that a first annular spacing is defined between the first and second elongated tubular members when the second elongated tubular member is inserted into the first lumen; a containment bag selectively deployable from the cannula arrangement; a deployment plunger including a proximal base and characterised by a plurality of engagement fingers extending distally from the proximal base, the plurality of engagement fingers configured for insertion through the first annular space; and an inner cannula including a third elongated tubular member defining a third lumen extending therethrough and configured for insertion into the second lumen, the third elongated tubular member defining a diameter less than a diameter of the second elongate tubular member such that a second annular spacing is defined between the second and third elongated tubular members when the third elongated tubular member is inserted into the second lumen; and wherein distal advancement of the deployment cannula relative to the access cannula deploys a first portion of the containment bag from the cannula arrangement, and wherein distal advancement of the deployment plunger relative to the deployment cannula and the access cannula deploys a second portion of the containment bag from the cannula arrangement. an access cannula including a first elongated tubular member defining a first lumen extending therethrough; a deployment cannula including a second elongated tubular member defining a second lumen extending therethrough and configured for insertion into the first lumen, the second elongated tubular member defining a diameter less than a diameter of the first elongate tubular member such that a first annular spacing is defined between the first and second elongated tubular members when the second elongated tubular member is inserted into the first lumen; a containment bag selectively deployable from the cannula arrangement; a deployment plunger including a proximal base and characterised by a plurality of engagement fingers extending distally from the proximal base, the plurality of engagement fingers configured for insertion through the first annular space; and an inner cannula including a third elongated tubular member defining a third lumen extending therethrough and configured for insertion into the second lumen, the third elongated tubular member defining a diameter less than a diameter of the second elongate tubular member such that a second annular spacing is defined between the second and third elongated tubular members when the third elongated tubular member is inserted into the second lumen; and wherein distal advancement of the deployment cannula relative to the access cannula deploys a first portion of the containment bag from the cannula arrangement, and wherein distal advancement of the deployment plunger relative to the deployment cannula and the access cannula deploys a second portion of the containment bag from the cannula arrangement.