Evaluation of stereotactic core needle biopsy (SCNB) of the breast at a single institution

[Minimally invasive biopsy and preoperative marking of suspect mammary lesions]

Image-guided minimally invasive needle biopsy is an established method in the diagnosis of breast cancer, which - when indicated correctly and carried out with quality control - equals or even surpasses open diagnostic surgery. Therefore, an open diagnostic biopsy should only be performed as well-founded exception. Depending on the visibility in the various diagnostic techniques of the condition to be clarified histologically, needle biopsy has to be carried out with the image-guided procedure which can identify the mammary lesion most reliably. If a lesion is detectable mammographically as well as sonographically, a high-speed large-core biopsy is preferred, taking the strain on the patient and the costs into account, too. In the case of suspect microcalcifications, the needle biopsy has to be controlled stereotactically. Here, vacuum-assisted procedures [Mammotome, VacuFlash (BIP)/Vacora (Bard)] yield markedly better results when compared with large-core biopsy and are also preferred for lesions which are only visible on magnetic resonance tomography. Without exception, preoperative wire marking should be used in cases of suspect nonpalpable lesions in imaging diagnostics or even more so of lesions which have already been classified histologically as malignant by minimally invasive procedures before surgery. This is the only way to safely find the suspect and nonpalpable lesion during the operation and to excise it with a sufficient safety margin while preserving as much healthy issue as possible. Quality-controlled diagnostics and therapy of breast cancer constitute an interdisciplinary challenge and yield optimal results only when all concerned specialties collaborate in the best possible way.

[Stereotaxic breast biopsy techniques have become the standard of care for mammographically suspicious lesions]

An optimal technique for the evaluation of nonpalpable, suspicious mammographic lesions should have a low technical failure rate, no false-negative results and should remove the lesion completely. Since most of these lesions are benign, the procedure should be carried out in an outpatient setting without general anesthesia. Cancer is missed in 2.6% of cases with excisional biopsy following needle localization. Furthermore, 50-83% of these patients undergo a second surgical intervention for definitive surgical treatment. In contrast, the rate of missed cancers is less than 0.7% following stereotaxic core or large-core biopsies. However, using these techniques, discordant results and histologic high-risk lesions need to be recognized and reexcized. The cost-effectiveness of stereotaxic vacuum-assisted core biopsy has been demonstrated. Stereotaxic breast biopsy techniques such as vacuum-assisted core biopsy and large-core biopsy for suspicious mammographic lesions have low false-negative rates and result in few histologic underestimations.

Stereotactic large core needle biopsy for all nonpalpable breast lesions?

BACKGROUND

Stereotactic large-core needle biopsy (SLCNB) is a minimally invasive method for histological diagnosis of nonpalpable breast disease. We studied differences in cancer prevalence between a group of women referred through the national screening program and a non-screening group, and assessed whether the validity of SLCNB differed between these groups.

METHODS

A group of non-selective, consecutive patients presenting with a nonpalpable mammographic lesion, who participated in a recently conducted multicenter study regarding the accuracy of SLCNB in The Netherlands, were the basis for this study. Prevalence of carcinoma, predictive value of a benign diagnosis, sensitivity, and specificity rate of SLCNB were compared between the two groups.

RESULTS

Of the 1029 lesions in 972 patients included, 858 were evaluable. In 850/858 lesions (99.1%) the reason for referral was clear. The prevalence of cancer in the screening group (n = 511 lesions) was 64.0% (95%CI 59.8-68.2), versus 49.6% in the non-screening group (n = 339) (95%CI 44.2-54.9). Respective predictive values of a benign diagnosis on SLCNB were 97.0 versus 94.8% (non-significant). The sensitivity rates of SLCNB were 98.5% (screening; 95%CI 96.5-99.5) versus 95.2% (non-screening; 95%CI 90.8-97.9). Specificity rates were 97.8 (95%CI 94.5-99.4) and 99.4% (95%CI 96.8-100), respectively.

CONCLUSION

Despite a significant difference in the prevalence of carcinoma, the accuracy of SLCNB did not show a statistically significant difference between both patient groups. Therefore, SLCNB appears accurate in diagnosing nonpalpable breast lesions both in screening and non-screening patient groups.

Histologic and radiographic analysis of ductal carcinoma in situ diagnosed using stereotactic incisional core breast biopsy

BACKGROUND

Stereotactic incisional core breast biopsy (SCBB) is a highly specific technique for diagnosing ductal carcinoma in situ (DCIS) in patients with suspicious mammographic microcalcifications. However, its sensitivity for excluding the presence of coexisting occult invasive disease in this setting is not fully established.

DESIGN

We correlated SCBB findings to subsequent lumpectomy/mastectomy (lx/mx) results in 122 cases of DCIS. In 29 of these cases, the SCBB showed microscopic invasion (n = 15) or foci that were suspicious for invasion (n = 14). Likelihood for invasive disease in subsequent lx/mx samples from each case then was compared with various parameters, including DCIS grade, extent and mammographic findings.

RESULTS

Overall, 13% of cases in which the SCBB showed DCIS only (i.e., without any evidence of invasion), had invasive disease in the subsequent excision. This finding was significantly correlated with DCIS grade (low: 0/26 [0%], intermediate: 2/31 [6%], high: 10/36 [28%], P <.001). Invasive lesions were usually small (nine T1a, one T1b, and two T1c) and typically present within more extensive fields of DCIS (no invasion: 1.5 cm DCIS size; invasion: 2.8 cm mean DCIS size, P =.01). This was reflected by greater extent of involvement in the SCBB (5/8 cases with invasion had >15 ducts involved, versus 4/23 with <15 ducts involved, P =.03). SCBB that were suspicious or positive for microinvasion demonstrated invasion in most subsequent excision (susp: 7/14 [50%], microinv: 11/15 [73%]), generally of significant extent (11/18 T(1b-c)).

CONCLUSIONS

1. Patients with SCBB showing high grade DCIS and DCIS suspicious or positive for microinvasion have a significant and high likelihood, respectively, of harboring occult invasive neoplasm. They should accordingly be carefully evaluated radiographically, and possibly with sentinel node biopsy to facilitate axillary staging. 2. Likelihood of occult invasion is correlated with overall DCIS size/extent.

Adequate histologic sampling of breast core needle biopsies

OBJECTIVE

To determine the degree of histologic sampling necessary for adequate examination of breast core needle biopsy specimens.

DESIGN

The results of all breast core needle biopsies (11 and 14 gauge) with a diagnosis of atypical small acinar proliferation or atypical ductal hyperplasia and subsequent excisional biopsies, for a 50-month period were reviewed. Blocks of all cores were sectioned entirely in 8 slides to determine the amount of sectioning needed to detect these foci, and the results were correlated with those from the excision specimen.

SETTING

Large community hospital practice.

RESULTS

Of 3026 cases, 216 (7.1%) were diagnosed as atypical ductal hyperplasia or atypia not otherwise specified. Subsequent resections were available in 105 (49%) cases, and after review, 95 (92%) qualified as atypical ductal hyperplasia and 2 were determined to be atypical small acinar proliferations. The 2 small acinar proliferations were first detected on the second and fourth slides. Of the atypical ductal hyperplasia cases, 43% were detected on the first slide, 17% on the second, 23% on the third, 8% on the fourth, and 8% on the fifth. No lesions were initially detected after this level. Ductal carcinoma in situ was detected in the excision specimens from 1 case each of those detected initially on the fourth and fifth slides.

CONCLUSION

Five sections of breast core needle biopsy specimens are necessary to ensure that all atypical small acinar proliferations and atypical ductal hyperplasia lesions are sampled.

Atypical ductal hyperplasia in breast core needle biopsies. Correlation of size of the lesion, complete removal of the lesion, and the incidence of carcinoma in follow-up biopsies

We reviewed the results of all breast core needle biopsies with a diagnosis of atypical ductal hyperplasia (ADH) or atypia not otherwise specified and subsequent excisional biopsies for a 50-month period and correlated the results. Of 3,026 biopsies, 216 were diagnosed as ADH or atypia not otherwise specified, and subsequent resection was available for 105. After review, 95 qualified as ADH. Subsequent resection showed ductal carcinoma in situ (DCIS) in 13 excisions, ADH in 31, lobular carcinoma in situ in 6, and benign proliferative lesions in the remaining 45. In none of the 8 biopsies in which DCIS was found and radiographs were available for review was the radiographic lesion entirely removed. For comparison, the incidence of carcinoma in resections done for a diagnosis of DCIS, low or intermediate grade (solid, cribriform, or micropapillary type), on core needle biopsy was significantly greater (8 of 10 cases). However, the size of the lesions diagnosed as carcinoma also was significantly greater than that of the lesions diagnosed as ADH, and in none of the 8 biopsies with DCIS at excision was the lesion entirely removed at the time of biopsy. The incidence of carcinoma in excisional biopsies done for a diagnosis of ADH in core needle biopsies in our institution is relatively low, while the incidence of ADH is relatively high. Possible reasons for this include total removal of small lesions at the time of biopsy and use of the diagnostic term ADH for lesions that are not associated with coexistent DCIS.

Improved reporting methods for atypia and atypical ductal hyperplasia in breast core needle biopsy specimens. Potential for interlaboratory comparisons

The incidence of atypia and atypical ductal hyperplasia (ADH) in breast core needle biopsies varies widely (900%). I sought to identify methods to reduce the dependence of this measure on variability in the patient population. The results of all breast core needle biopsies with a diagnosis of ADH or atypia not otherwise specified for a 50-month period were reviewed. These were separated into different groups by age, and the variability of different reporting methods was compared. Of 3,026 cases, 216 were diagnosed as ADH or atypia not otherwise specified. The overall incidence of atypia by age group varied significantly from 0.029 to 0.10. The variability was reduced when atypia was expressed in relation to ductal carcinoma in situ (range, 1.0-2.1) or fibrocystic changes (range, 0.15-0.28). However, variability by age was the least when atypia was expressed in relation to the number of cases performed for calcifications (range, 0.13-0.17). Variability in atypia rates associated with age is reduced significantly when atypia is expressed in relation to the number of biopsies done for calcifications. This method of reporting atypia may allow interlaboratory comparisons with less dependence on the characteristics of the patient population.