Today, needle biopsy is an essential technique for preoperative diagnosis of breast cancer. One of the major causes of false negatives in needle biopsy diagnosis is that the lesion was not properly biopsied [6 ~ 8]. If the macroscopic findings of the needle biopsy specimen match the expected histopathological results, it can be judged that the needle biopsy was properly performed. Our literature search found that Rosen p.p. performed detailed examination of the gross findings for excised fresh specimens , but we found no reports of studies of needle biopsy specimens. Our present report is thus the first to examine needle biopsy specimens in detail.
This was a retrospective study. Specimens were photographed with an iPhone. This is because the number of pixels of the iPhone camera, 12 million, was judged to be sufficient for documenting the specimens properties, while the camera can be easily used in ordinary facilities. A commercial, readily-available illumination device was used for tangential lighting. Rosen p.p. had used tangential light to observe excised specimens, and we judged that tangential light was suitable for accurately observing the surface properties of our needle biopsy specimens. In addition, we examined VAB specimens because larger specimens can be evaluated compared to core needle biopsy (CNB) specimens.
As macroscopic findings, we examined only the 1) presence/absence of turbidity, 2) surface properties, 3) presence/absence of calcification and 4) characteristic findings. Turbidity was examined because it has been thought to be associated with an increase in cell components. The surface properties were examined because they have been thought to reflect the influence of tumors on the stroma. White spots were examined because they are thought to represent microcalcifications. Our terminology for the characteristic findings was based on the terminology used for gastrointestinal endoscopic findings . The findings were retrospectively reviewed and classified. We did not evaluate the color of our VAB specimens because Rosen p.p. reported that, for their excised specimens, even invasive ductal carcinoma (IDC) exhibited a range of colors (white, gray and yellow) . Regarding the pathological results, because the number of evaluated cases was small, all the cases of breast cancer were considered malignant, and we did not examine for a relationship with the histopathological result. On the other hand, for cases of benign disease, we did examine the presence/absence of turbidity and the characteristic findings for relationships with the histopathological result.
Our results indicate that malignancy was significantly more frequent in specimens with turbidity and a rough surface. Furthermore, the malignancy rate was 96% for specimens with both turbidity and a rough surface. In addition, only 13% of our specimens had white spots due to microcalcification, but their rate of malignancy was significantly high. Collectively, specimens showing turbidity, specimens with a rough surface, and specimens with white spots were significantly more likely to be malignant. Also, the presence/absence of microcalcifications was able to be confirmed by visual observation.
Next, specimens with a circular granular structure as a characteristic finding had a malignancy rate of 42%, while the rate was 50% for specimens with contraction. Although papillary structures are common in IDP, 32% were malignant. In addition, edema and red cord-like structures were found to be characteristic of FA. In Rosen p.p. study using fresh samples, radial sclerosing lesions, which are benign disease, had a retracted center with white streaks, while cases with adenosis had abundant calcifications and appeared to be gritty. On the other hand, for IDC they wrote that “the appearance of the cut surface very considerably depended on the composition of the tumor,” etc. . Excised specimens and VAB specimens differ not only in size: it is predicted that excised specimens often include normal mammary gland tissue, and the macroscopic findings are also expected to differ between these two types of specimen. In the future it will be necessary to investigate VAB specimens for a relationship between their macroscopic findings and histopathological results.
This study has a number of limitations. (1) The results of the dedicated imager and smartphone should be compared and examined, but we did not do this. (2) Turbidity and surface properties are subjective evaluations, and a multi-institutional reproducibility study is needed. (3) It is necessary to investigate whether CNB specimens can also be used. (4) This was a retrospective study, and a prospective study needs to be carried out.
Although the number of evaluated VAB specimens was small, it was found that the pathological results (benign/malignant) can be predicted from the macroscopic findings. In the future, it will be necessary to conduct reproducibility and prospective studies at multiple institutions.