Scar formation after breast-conserving surgery for cancer. Sir Charles Gairdner Hospital Breast Cancer Group

Residual disease after re-excision for tumour-positive surgical margins in both ductal carcinoma in situ and invasive carcinoma of the breast: The effect of time

BACKGROUND AND OBJECTIVES

To assess the effect of time on finding residual breast cancer in re-excision specimens after non-radical breast-conserving surgery for both DCIS and invasive breast carcinoma.

METHODS

315 breast-conserving surgical procedures with tumour-positive margins were retrospectively reviewed. The significance of association between the presence of finding residual tumour in the re-excision specimen and mean time interval was calculated with Student's t-test. A multivariate logistic regression model was used to assess the independent relative risk of time on presence of residual tumour.

RESULTS

Residual tumour was found in 240 (76.2%) of the re-excision specimens. For primary invasive carcinomas time was a risk-reducing factor for finding residual disease (OR 0.89, 95% CI 0.82-0.98, P = 0.01). If invasive carcinoma was transected, the absence of residual disease was significantly related with a longer mean time interval (OR 0.98, 95% CI 0.95-0.99, P = 0.04).

CONCLUSIONS

An increased time interval between primary surgery and re-excision for tumour-positive surgical margins for invasive carcinoma is associated with a decreased incidence of finding residual tumour. This could be explained by inflammatory responses after surgical trauma. For DCIS there was no influence of time on finding residual tumour, which could be explained by a more protective microenvironment of DCIS or re-growth of surviving malignant cells.

Scar formation after stereotactic vacuum-assisted core biopsy of benign breast lesions

AIM

To evaluate scar formation of impalpable breast lesions with benign histological outcome using stereotactic 11-gauge vacuum-assisted core biopsy (VACB).

MATERIALS AND METHODS

Two hundred and ten lesions with benign histology for which follow-up mammograms were available, were assessed for scar formation at the biopsy site. All biopsies were performed using stereotactic VACB with 11-gauge needle. The incidence of post-biopsy scar formation and the number of specimens removed were determined.

RESULTS

In 4.3% (9/210) of the lesions for which a biopsy was performed with 11-gauge directional vacuum-assisted technique, the follow-up mammogram revealed a scar formation. Of these, six were minimal scars, two were moderate scars and one was a marked scar. Minimal and moderate scars were diagnosed on imaging only. However, the case with marked scar formation required tissue diagnosis to rule out malignancy.

CONCLUSION

Although uncommon, scar formation can be seen in the follow-up mammograms after percutaneous breast biopsies. It is important that the radiologist interpreting follow-up mammograms is aware of the features of this lesion and its relationship to the biopsy procedure.

A cosmetic evaluation of breast cancer treatment: A randomized study of radiotherapy boost technique

PURPOSE

To compare cosmetic results of two different radiotherapy (RT) boost techniques used in the treatment of breast cancer after whole breast radiotherapy and to identify factors affecting cosmetic outcomes.

METHODS AND MATERIALS

Between 1996 and 1998, 142 patients with Stage I and II breast cancer were treated with breast conservative surgery and adjuvant RT. Patients were then randomly assigned to receive a boost dose of 15 Gy delivered to the tumor bed either by iridium 192, or a combination of photons and electrons. Cosmetic evaluations were done on a 6-month basis, with a final evaluation at 36 months after RT. The evaluations were done using a panel of global and specific subjective scores, a digitized scoring system using the breast retraction assessment (BRA) measurement, and a patient's self-assessment evaluation. As cosmetic results were graded according to severity, the comparison of boost techniques was done using the ordinal logistic regression model. Adjusted odds ratios (OR) and their 95% confidence intervals (CI) are presented.

RESULTS

At 36 months of follow-up, there was no significant difference between the two groups with respect to the global subjective cosmetic outcome (OR = 1.40; 95%CI = 0.69-2.85, p = 0.35). Good to excellent scores were observed in 65% of implant patients and 62% of photon/electron patients. At 24 months and beyond, telangiectasia was more severe in the implant group with an OR of 9.64 (95%CI = 4.05-22.92, p < 0.0001) at 36 months. The only variable associated with a worse global cosmetic outcome was the presence of concomitant chemotherapy (OR = 3.87; 95%CI = 1.74-8.62). The BRA value once adjusted for age, concomitant chemotherapy, and boost volume showed a positive association with the boost technique. The BRA value was significantly greater in the implant group (p = 0.03). There was no difference in the patient's final self-assessment score between the two groups. Three variables were statistically associated with an adverse self-evaluation: an inferior quadrant tumor localization, postoperative hematoma, and concomitant chemotherapy.

CONCLUSIONS

Although this trial showed that at 36 months of follow-up, there were no significant differences in the overall global cosmetic scores between the implant boost group and the photon/electron boost group, telangiectasia was more severe and the BRA value was greater in the implant group.

Effect of time interval on residual disease in breast cancer

The histologic responses of breast tissue to injury are limited. Needle core biopsies of the breast are associated with displacement of tumor cells, and the incidence of tumor displacement decreases as the time interval between needle core biopsy and subsequent excision increases. This suggests that displaced tumor cells are destroyed by reparative processes induced by tissue injury. Residual tumor in a lumpectomy site may also be subjected to the same destructive processes associated with tissue repair. A total of 259 consecutive cases of infiltrating ductal carcinoma with margin-positive lumpectomies and their associated reexcision specimens obtained over a 7-year period were analyzed for the presence, type, and quantity of residual disease. The overall incidence of residual disease was 69%. Residual infiltrating ductal carcinoma was present in 35% of cases, and residual ductal carcinoma in situ was present in 50%. An increased time interval between lumpectomy and reexcision was associated with a decreased incidence of residual infiltrating carcinoma (p <0.0043); this decrease was not found associated with ductal carcinoma in situ. These findings suggest that the host response to injury may destroy residual infiltrating carcinoma cells in some margin-positive cases.

Diagnosis of breast tumors after breast reduction

We conducted a retrospective study to evaluate the diagnosability of breast tumors after breast reductions as this is a frequent surgical procedure. The data should shed light on the hypothesis that routine screening methods concerning the diagnosis of breast tumors prove more difficult after breast operations. All women who had undergone breast reduction at our department between January 1989 and December 1994 were examined. During this period we counted 166 patients; the majority of them (n = 144) had undergone a bilateral breast reduction and the rest of them (n = 22) a unilateral breast reduction for various reasons. After the operation, all patients were checked in standardized intervals. Those who developed any kind of breast mass (n = 6) were recorded and examined by ultrasound and mammography, and occasionally by an additional fine-needle biopsy. In case any doubt about the dignity had remained, an excisional biopsy was carried out. In none of our patients was it possible to get a precise diagnosis of an ill-defined mass with ultrasound. With mammography, some of the existing masses, which were really scars, mimicked different kinds of tumors, and once a carcinoma was initially interpreted as scar tissue with oil cysts. The diagnosis of breast masses after breast reductions with routinely used screening methods has proved to be more difficult as breast reductions lead to architectural alterations of the remaining breast parenchyma. Such alterations can and should be documented shortly after the operation so that later occurring tumors are distinguished more easily. Therefore, a basic mammography 3 months after each breast reduction has to be claimed in order to facilitate further breast tumor diagnosis.

New aspects in the histological diagnosis of breast carcinoma

The wide use of mammographic screening and breast conservation surgery, as well as the introduction of a variety of new morphological and immunohistological assessment methods, has markedly changed the practice of breast histopathology. These changes have led to the emergence of new macroscopic and microscopic interpretation demands and difficulties. It is hoped that in the future the role played by diagnostic histopathology in the management of breast cancer will continue to be refined, so that it can provide more detailed information about individual tumors that will help in deciding the most likely approach to obtain the best treatment results.