BMC Cancer 2009, 9:254 http://www.biomedcentral.com/1471-2407/9/254 margins" technique on the BCS specimen itself is not nec- essarily a true reflection of what is going on directly at the surface of the BCS specimen itself, since it represent the action of sectioning directly into the peripheral tissues of the BCS specimen, a process which compromises the integrity of the periphery of the BCS specimen and is potentially fraught with many technical issues [82]. In our estimation, a "selective cavity margin sampling" tech- nique for the BCS resection bed cavity, which essential represents an equivalent to the "tangential shaved mar- gins" technique on the BCS specimen itself and which allows for a greater percentage of the surface area of breast tissue directly adjacent to the periphery of the BCS speci- men itself (i.e., the BCS resection bed cavity) to be availa- ble for surgical resection margin assessment (but without compromising the integrity of the BCS specimen itself) is a better solution. Therefore, as is the basis of our current paper, when our nine standardized re-resection margin technique is used as the "selective cavity margin sam- pling" technique for the BCS resection bed cavity and is combined with the generally accepted "perpendicular margins" technique for assessment of surgical resection margins on the BCS specimen itself, we believe that we can achieved the "best of both worlds" with regards to the development of a standardized and reproducible method- ology for the comprehensive and systematic assessment of surgical resection margins during BCS. Such a combined approach gives rise to the concept of optimizing the deter- mination of region clearance of tumor burden within the affected breast by taking into account both the potential for microscopically recognized or unrecognized compro- mise of the surgical resection margins of the BCS speci- men itself, as well as the potential for unrecognized multifocality of disease within the same quadrant of the affected breast. Multiple authors [16,47,49,68,83] have previously dis- cussed the technical issues related to the generation of false positive margins on BCS specimens. General hand- ing of the BCS specimen (that can take place either before or after normal specimen processing and inking that occurs in the pathology department), as well as specimen compression at the time of specimen mammography, can significantly impact upon the creation of artificially close or false positive margins. Due to the friable and lobular nature of the surfaces of both the fibrofatty tissue compo- nent and mammary tissue component comprising the freshly excised BCS specimen, any compression to the freshly excised BCS specimen can create artificial crevices, tissue thinning, and reorientation of the overlying fibro- fatty tissue and mammary tissue covering the actual tumor surface. This can result in decreasing the actual distance between the surface of the freshly excised BCS specimen and the surface of the tumor, as well as result in a change in the orientation of which surface of the freshly excised BCS specimen actually represents the true, closest margin. The subsequent application of ink to the friable and lob- ular surfaces of the freshly excised BCS specimen, and as accentuated by the previous above described effect of specimen compression, can result in the ingress of ink into these artificial crevices and potential spaces located in between the uneven, friable, and lobular surfaces of the freshly excised BCS specimen that ultimately allows for tracking and deposition of ink into locations more closely approximating the surface of the tumor than are actually representative of the true distance from the intended mar- gin surface of the freshly excised BCS specimen to the actual tumor surface. Additionally, the utilization of over- generous amounts of ink, as well as the addition of any excess force during the process of ink application to the freshly excised BCS specimen and during the process of removal of excess ink (i.e., "blotting dry") from the freshly excised BCS specimen can further accentuate the ingress of ink into potential spaces that are not representative of the intended margin surface of the freshly excised BCS speci- men. Taken together, all these above describe variables may lead to the generation of artificially elevated false positive margin rates and may be a major contributing fac- tor in the alarmingly high rate of margin positivity reported in many of the studies shown in Table 12[20- 68]. Better education of those individuals that are directly involved in specimen transport, specimen mammo- graphic evaluation, and specimen processing within the pathology department may help to reduce these poten- tially preventable causes of an artificially elevated rate of margin positivity on BCS specimens. When one reflects on the overall alarmingly high rate of margin positivity reported by many previous series in the literature and which is clearly illustrated within Table 12[20-68], the validity of such data that is thought to rep- resent homogenous populations of patients undergoing definitive BCS then comes into question. Clearly, some of these previous reported series not only included individ- ual undergoing a definitive BCS procedure, but also indi- viduals undergoing only a diagnostic surgical excisional breast biopsy. This subtle distinction was generally not well articulated by the authors of such papers, and this factor, in many cases, may have accounted for their rela- tively high reported margin positivity rates. Two recent studies have clearly addressed this issue [58,64]. Lovrics et al [64] nicely illustrated the significance of having a con- firmed preoperative diagnosis of invasive breast cancer on margin positivity with BCS. They showed that 19.6% (65/ 332) of patients had positive margins (defined by tumor at cut edge) on BCS specimens when there was a con- firmed preoperative diagnosis of invasive breast cancer while 26.0% (127/489) of patients had positive margins on BCS specimens when they included those patients without a confirmed preoperative diagnosis of invasive Page 19 of 23 (page number not for citation purposes)