Lumpectomy and radiation treatment for invasive lobular carcinoma of the breast

Breast conservation therapy versus mastectomy in the surgical management of invasive lobular carcinoma measuring 4 cm or greater

BACKGROUND

The safety of breast conservation therapy (BCT) has not been demonstrated in large ILC tumors, potentially contributing to the higher mastectomy rates seen in ILC.

METHODS

We queried a prospectively maintained database to identify patients with ILC measuring ≥4 cm and evaluated difference in recurrence free survival (RFS) between those treated with BCT versus mastectomy using a multivariate model.

RESULTS

Of 180 patients, 30 (16.7%) underwent BCT and 150 (83.3%) underwent mastectomy. Patients undergoing mastectomy were younger (56.6 vs. 64.3 years, p = 0.003) and had larger tumors (7.2 vs. 5.4 cm, p < 0.001). While tumor size, nodal stage, receptor subtype, and margin status were significantly associated with RFS, there was no difference in RFS at 5 (p = 0.88) or 10 (p = 0.65) years for individuals undergoing BCT versus mastectomy.

CONCLUSIONS

For patients with ILC ≥4 cm, BCT provides similar tumor control as mastectomy, provided that negative margins are achieved.

Invasive Lobular Breast Cancer as a Distinct Disease: Implications for Therapeutic Strategy

Invasive lobular carcinoma comprises 10-15% of all breast cancers and is increasingly recognised as a distinct and understudied disease compared with the predominant histological subtype, invasive ductal carcinoma. Hallmarks of invasive lobular carcinoma include E-cadherin loss, leading to discohesive morphology with cells proliferating in single-file strands and oestrogen receptor positivity, with favourable response to endocrine therapy. This review summarises the distinct histological and molecular features of invasive lobular carcinoma with focus on diagnostic challenges and the impact on surgical management and medical therapy. Emphasis is placed on recent advances in our understanding of the unique molecular biology of lobular breast cancer and how this is optimising our therapy approach in the clinic.

Outcomes in women with invasive ductal or invasive lobular early stage breast cancer treated with anastrozole or exemestane in CCTG (NCIC CTG) MA.27

BACKGROUND

Histological subtype, (invasive ductal breast cancer (IDBC)/invasive lobular breast cancer (ILBC)), might be a marker for differential response to endocrine therapy in breast cancer.

METHODS

Clinical trial MA.27 compared 5 years of adjuvant anastrozole or exemestane in postmenopausal patients with hormone receptor positive early breast cancer. We evaluated IDBC versus ILBC (based on original pathology reports) as predictor for event-free survival (EFS) and overall survival (OS).

RESULTS

A total of 5709 patients (5021 with IDBC and 688 with ILBC) were included (1876 were excluded because of missing or other histological subtype). Median follow-up was 4.1 years. Overall, histological subtype did not influence OS or EFS (HR (hazard ratio) 1.14, 95% confidence interval (CI) [0.79-1.63], P = 0.49 and HR 1.04, 95% CI [0.77-1.41], P = 0.81, respectively). There was no significant difference in OS between treatment with exemestane versus treatment with anastrozole in the IDBC group (HR = 0.92, 95% CI [0.73-1.16], P = 0.46). In the ILBC group, a marginally significant difference in favour of treatment with anastrozole was seen (HR = 1.79, 95% CI [0.98-3.27], P = 0.055). In multivariable analysis a prognostic effect of the interaction between treatment and histological subtype on OS (but not on EFS) was noted, suggesting a better outcome for patients with ILBC on anastrozole (HR 2.1, 95% CI [0.99-4.29], P = 0.05). After stepwise selection in the multivariable model, a marginally significant prognostic effect for the interaction variable (treatment with histological subtype) on OS (but not on EFS) was noted (Ratio of HR 2.1, 95% CI [1.00-4.31], P = 0.05).

CONCLUSION

Our data suggest an interaction effect between treatment and histology (P = 0.05) on OS. Here, patients with ILBC cancers had a better OS when treated with anastrozole versus exemestane, whereas no difference was noted for patients with IDBC.

CLINICAL TRIAL INFORMATION

NCT00066573.

Clinical-pathologic features, long term-outcome and surgical treatment in a large series of patients with invasive lobular carcinoma (ILC) and invasive ductal carcinoma (IDC)

PURPOSE OF THE STUDY

A retrospective analysis on 1407 patients with invasive ductal carcinoma (IDC) and 243 invasive lobular carcinoma (ILC) was performed in order to compare the histological features, the immunohistochemical characteristics, the surgical treatment and the clinical outcome in the two groups.

RESULTS

ILC seems to be more likely multifocal, estrogen receptor positive, HER-2 negative and to have a lower proliferative index compared to IDC. ILC, when treated with conservative surgery, required more frequently re-excision and/or mastectomy because of positive resection margins. No difference was observed in terms of 5-year disease free survival and local relapse free survival between the two groups, in the whole series and in the subgroup of patients treated with breast-conserving treatment.

CONCLUSION

ILC can be safely treated with conservative surgery but a more accurate preoperative evaluation of tumor size and multifocality could be advocated, in order to reduce the re-excision rate.

Comparison of mastectomy with breast-conserving surgery in invasive lobular carcinoma: 15-Year results

BACKGROUND

Invasive lobular cancer (ILC) is biologically distinct from invasive ductal cancer and there is disagreement regarding appropriate local management of this disease.

AIM

The current study reports long term results comparing mastectomy with breast-conserving surgery (BCS) in the treatment of ILC.

MATERIAL AND METHODS

Study includes 235 women with ILC treated between 1983 and 1987. All of them underwent axillary dissection and either mastectomy (n = 163) or BCS (n = 72). 50 Gy adjuvant radiotherapy (RT) was given for 53 BCS and 81 mastectomy patients. The BCS group was compared with the mastectomy group.

RESULTS

Patients treated with mastectomy or BCS had a similar outcome at 15 years with regard to distant metastasis-free (62% vs. 70%; p, 0.2017) and breast cancer-specific (62% vs. 70%; p, 0.1728) survival. In the BCS group the actuarial rate of ipsilateral in breast recurrences was 10% with and 53% without RT at 15 years (relative risk [RR], 0.10; p < 0.0001). In the mastectomy group the actuarial rate of chest wall recurrences was 16% with and 13% without RT at 15 years (RR, 1.45; p, 0.3965). Isolated ipsilateral in breast recurrence did not (RR, 1.73; p, 0.2767) but isolated chest-wall recurrence did (RR, 2.65; p, 0.0089) adversely affect cause-specific survival.

CONCLUSION

Breast cancer specific survival is not affected by the type of surgical treatment. BCS and RT is a safe option to control local disease in patients with ILC.

Invasive lobular carcinoma of the breast: should this be regarded as a chronic disease?

BACKGROUND

The surgical treatment of patients with invasive lobular carcinoma is still controversial due to its different clinical and pathological features. Most studies report local recurrence after relatively short follow-up periods, which is usually 5 years. However there is some evidence to suggest that local recurrence may occur late in the course of follow-up.

AIM OF THE STUDY

To study the implications and outcome of extending the follow-up period of patients treated for invasive lobular carcinoma.

PATIENTS AND METHODS

Patients (268) treated between 1989 and 1996 were reviewed. Thirty-three patients were excluded as they had primary hormonal therapy. The outcomes for 235 patients were analyzed.

RESULTS

Seventy-nine patients (33.6%) had breast conservation surgery (group I), which was followed by re-excision due to positive margins in 23 patients (29%), and 156 patients (66.3%) had mastectomy (group II). Compared to group II, tumours in group I were smaller (mean size 17 vs. 37 mm, P=0.001), multifocal [20 (25%) vs. 14 (9%), P=0.003] and with more positive margins [23 (29%) vs. 24 (15%), P=0.0009]. Only 33 patients (21%) in group II, and all patients in group I had post-operative radiotherapy (P=0.0001). Forty-eight patients (17.9%) developed local recurrence [27 (34%) in group I and 21 (13.4%) in group II, P=0.0005] after a median follow-up period of 167.8 months. The mean time to local recurrence was 127 (range 24-196) months. Univariate analysis showed that the type of surgery, margin status, adjuvant radiotherapy and chemotherapy significantly affected local recurrence (P=0.0005, 0.02, 0.04 and 0.05 respectively). Cox regression analysis showed that the only factor affected local recurrence was the type of surgery (relative risk 2.43, 95% confidence interval 1.22-4.83, P=0.01) The overall survival was 99.3 months (78.2%). Univariate and Cox regression analyses showed that only the patients age at diagnosis significantly affected survival (P=0.003).

CONCLUSION

Local recurrence may be a late event in patients treated for invasive lobular carcinoma of the breast and extended follow-up may be considered. In this study mastectomy offers better local control.

Patient selection for accelerated partial-breast irradiation (APBI) after breast-conserving surgery: recommendations of the Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) breast cancer working group based on clinical evidence (2009)

PURPOSE

To give recommendations on patient selection criteria for the use of accelerated partial-breast irradiation (APBI) based on available clinical evidence complemented by expert opinion.

METHODS AND MATERIALS

Overall, 340 articles were identified by a systematic search of the PubMed database using the keywords "partial-breast irradiation" and "APBI". This search was complemented by searches of reference lists of articles and handsearching of relevant conference abstracts and book chapters. Of these, 3 randomized and 19 prospective non-randomized studies with a minimum median follow-up time of 4 years were identified. The authors reviewed the published clinical evidence on APBI, complemented by relevant clinical and pathological studies of standard breast-conserving therapy and, through a series of personal communications, formulated the recommendations presented in this article.

RESULTS

The GEC-ESTRO Breast Cancer Working Group recommends three categories guiding patient selection for APBI: (1) a low-risk group for whom APBI outside the context of a clinical trial is an acceptable treatment option; including patients ageing at least 50 years with unicentric, unifocal, pT1-2 (<or=30 mm) pN0, non-lobular invasive breast cancer without the presence of an extensive intraductal component (EIC) and lympho-vascular invasion (LVI) and with negative surgical margins of at least 2mm, (2) a high-risk group, for whom APBI is considered contraindicated; including patients ageing <or=40 years; having positive margins, and/or multicentric or large (>30 mm) tumours, and/or EIC positive or LVI positive tumours, and/or 4 or more positive lymph nodes or unknown axillary status (pNx), and (3) an intermediate-risk group, for whom APBI is considered acceptable only in the context of prospective clinical trials.

CONCLUSIONS

These recommendations will provide a clinical guidance regarding the use of APBI outside the context of a clinical trial before large-scale randomized clinical trial outcome data become available. Furthermore they should promote further clinical research focusing on controversial issues in the treatment of early-stage breast carcinoma.

The impact of postmastectomy radiotherapy on local control in patients with invasive lobular breast cancer

PURPOSE

The aim of this population-based study was to examine the impact of postmastectomy radiotherapy on the risk of local recurrence in patients with invasive lobular breast cancer (ILC).

METHODS

The population-based Eindhoven Cancer Registry was used to select all patients with ILC, who underwent mastectomy in five general hospitals in the southern part of the Netherlands between 1995 and 2002. Of the 499 patients 383 patients fulfilled the eligibility criteria. Of these patients, 170 (44.4%) had received postmastectomy radiotherapy. The median follow-up was 7.2 years. Fourteen patients (3.7%) were lost to follow-up.

RESULTS

During follow-up 22 patients developed a local recurrence, of whom 4 had received postmastectomy radiotherapy. The 5-year actuarial risk of local recurrence was 2.1% for the patients with and 8.7% for the patients without postmastectomy radiotherapy. After adjustment for age at diagnosis, tumour stage and adjuvant systemic treatment, the patients who underwent postmastectomy radiotherapy were found to have a more than 3 times lower risk of local recurrence compared to the patients without (Hazard Ratio 0.30; 95% Confidence Interval: 0.10-0.89).

CONCLUSION

Local control is excellent for patients with ILC who undergo postmastectomy radiotherapy and significantly better than for patients not receiving radiotherapy.

Identifying patients at risk of compromised margins following breast conservation for lobular carcinoma

BACKGROUND

The association of invasive lobular carcinoma with high rates of compromised margins in breast conservation makes choice of operation for these patients difficult. We sought to identify patients at risk of compromised margins following breast conservation surgery.

METHODS

We reviewed all patients with invasive lobular and invasive ductal carcinoma over a 5-year period (1999-2004). The imaging, pathology and surgical details of patients with invasive lobular carcinoma undergoing breast conservation were analyzed.

RESULTS

A total of 991 patients with invasive ductal carcinoma and 150 patients with invasive lobular carcinoma were identified. Lobular carcinomas had a compromised margin rate of 49% (n = 38/77) in breast conservation compared to 24% (n = 143/588) of ductal carcinomas (P < .0001). Mammographic size (P = .017), pathological size (P = .01), age (P = .03), multifocality (P < .0001), and lymphovascular invasion (P = .015) were significantly associated with compromised margins.

CONCLUSION

Invasive lobular carcinoma has a 49% rate of compromised margins following breast conservation. Mammographic size greater than 1.5 cm and young age were preoperative factors predictive of compromised margins.

Ultrasonographic findings of invasive lobular carcinoma differentiation of invasive lobular carcinoma from invasive ductal carcinoma by ultrasonography

BACKGROUND

Although controversy exists, invasive lobular carcinoma (ILC) differs in its high frequency of microscopically positive margins after conservative therapy compared to invasive ductal carcinoma (IDC). If ILC could be recognized by imaging modalities, it would provide important information for surgeons. We tried to confirm whether it is possible to distinguish ILC from other invasive carcinomas by ultrasonography (US).

METHODS

A total of 81 histologically confirmed cases of IDC, including 26 cases of papillotubular carcinoma, 28 cases of solid-tubular carcinoma and 27 cases of scirrhous carcinoma, as well as 24 cases of ILC were selected and retrospectively studied with regard to the features of mass lesions on US examination.

RESULTS

The sensitivities of US for papillotubular carcinoma, solid-tubular carcinoma, scirrhous carcinoma and ILC were 88.5%, 100%, 92.6% and 91.7% respectively. We could divide invasive breast cancer into two groups by US findings. One group had a low frequency of malignant findings and consisted of papillotubular and solid-tubular carcinomas, and the other group had a high frequency of malignant findings and consisted of scirrhous carcinomas and ILC. However, there were no statistical differences between papillotubular carcinoma and solid-tubular carcinoma or between scirrhous carcinoma and ILC with regard to the US findings.

CONCLUSIONS

Scirrhous carcinoma, the most common type of IDC, and ILC are difficult to distinguish by US. Therefore it is difficult to separate ILC from IDC by US.

Treatment trends in early-stage invasive lobular carcinoma: a report from the National Cancer Data Base

OBJECTIVE

To examine treatment trends in invasive lobular carcinoma (ILC) over the last 15 years and, in particular, to compare rates of recurrence and disease-free survival associated with breast conservation therapy compared with mastectomy.

SUMMARY BACKGROUND DATA

The biologic characteristics of ILC make it difficult to estimate the extent of the disease by either clinical examination or mammography, and can also make it difficult to detect axillary lymph node metastases. Because of this, there has been a bias toward treating ILC with aggressive therapy.

METHODS

Patients with ILC were selected from the National Cancer Data Base (1989-2001) using an extensive set of inclusion and exclusion criteria. A total of 21,596 patients were selected, including 8108 who received breast conservation therapy and 13,488 who received mastectomy. Analysis included demographic characteristics, trends in usage of sentinel lymph node biopsy, rates of local and distant recurrence, and 5-year disease-free survival rates.

RESULTS

The use of breast conversation therapy increased almost threefold during the study period. From 1998 to 2001, the use of sentinel node biopsy increased more than twofold in the breast conservation group (an average of 23% in 1998 versus 57% in 2001), compared with limited usage in the mastectomy group (an average of 10% in 1998 versus 23% in 2001). Local recurrence rates were very low and disease-free survival rates were correspondingly high in both treatment groups for all diagnosis years and across all pathologic tumor size/lymph node status designations.

CONCLUSIONS

Less invasive treatment options are becoming widely used for invasive lobular carcinoma, yielding outcomes equivalent to those seen with more aggressive treatment.

Infiltrating lobular carcinoma—a comparison of diagnosis, management and outcome with infiltrating duct carcinoma

The treatment and outcomes for 182 patients with lobular carcinoma were compared with 1612 patients with infiltrating ductal carcinoma managed concurrently at The Strathfield Breast Centre. The lobular carcinomas were larger (P < 0.0001) but of lower grade (P < 0.0001). Diagnosis with mammography and FNA was less sensitive in ILC (mammography P = 0.0002, FNA P < 0.0001). Although similar numbers of patients underwent initial attempted conservation, patients with ILC were more likely to have positive margins at attempted breast conservation surgery and the final mastectomy rate was higher (58.2% ILC versus 47% IDC, P = 0.0041). Of the patients who had successful conservation, the local recurrence rates for ILC (3.9%) were equivalent to the patients with IDC (5.3%). There was no significant difference in overall survival (90% ILC, 87% IDC, median follow-up 3.6 years ILC, 4.3 years IDC) or disease free survival (87.9% ILC, 81.6% IDC). Although mastectomy is more likely to be necessary to obtain clear margins, breast conservation therapy is reasonable in patients with infiltrating lobular carcinoma where clear margins can be obtained.

Breast Conservation Therapy for Invasive Lobular Carcinoma: The Impact of Lobular Carcinoma in Situ in the Surgical Specimen on Local Recurrence and Axillary Node Status

Forty patients undergoing breast-conserving therapy for invasive lobular carcinoma were studied for the volume of lobular carcinoma in situ (LCIS) in the surgical specimen and its relationship to the surgical margins. The pathology of all cases was reviewed for margin status as well as the volume of LCIS in the surgical specimen. Mean follow-up time was 67 months. There were no local recurrences despite the fact that 38 per cent of patients had close or involved margins. There was one cancer-related death. Increasing tumor size and moderate or extensive involvement of the surgical specimen with LCIS were found to be independent predictors of axillary node metastases. The volume of LCIS in the surgical did not appear to have an impact on local recurrence. This paper adds to the growing body of literature suggesting that in patients undergoing breast-conserving therapy, LCIS in the surgical margin does not impact the risk of local recurrence and therefore may not require reexcision for close or involved surgical margins.

Surgical treatment for invasive lobular carcinoma of the breast

The management and outcome of 131 women with infiltrating lobular carcinoma treated in the Belfast City Hospital between October 1987 and February 1999 were reviewed. Two patients had primary hormonal treatment and were excluded from the statistical analysis, and 129 patients were followed up. Fifty-four patients (41%) had initial breast conservation surgery, which was followed by re-excision of margins in eight patients (14.8%) and completion total mastectomy in 26 patients (48.1%). The breast conservation surgery group, 28 patients (21.7%), was compared with the total mastectomy group, 101 patients (78.2%), after a median follow-up period of 90 months (range 24-160 months). The overall survival was 68.7%. Survival analysis was performed using Kaplan-Meier and Cox regression which showed that lymph node involvement and tumour grade were the only variables affecting survival (P<0.0001, and 0.01, respectively). The type of surgery performed did not affect survival (P=0.42). The total number of patients who developed local recurrence was 17 patients (13.1%, 12 patients in the breast conservation surgery group and five patients in the total mastectomy group, P<0.0001). Kaplan-Meier analysis of local recurrence showed that the type of surgery (P<0.0001), patient age (P=0.02), tumour grade (P=0.002), adjuvant radiotherapy (P=0.013), chemotherapy (P=0.031) and hormonal treatment (P=0.003) significantly affected local recurrence. Cox regression analysis showed that the only factor significantly affecting local recurrence was the type of surgery performed (P=0.02). Patients who underwent mastectomy had less local recurrence than those who had breast conservation surgery. Local recurrence after breast conservation surgery is high, even with clear surgical margins and post-operative radiotherapy. The authors believe that total mastectomy for infiltrating lobular carcinoma is a safer option to control local disease, especially in younger patients and those with high-grade tumours. Overall survival is not affected by the type of surgical treatment. Local recurrence can be a late event and a long-term follow-up is recommended.

Differences in risk factors for local and distant recurrence after breast-conserving therapy or mastectomy for stage I and II breast cancer: pooled results of two large European randomized trials

PURPOSE

Risk factors for local and distant recurrence after breast-conserving therapy and mastectomy were compared to define guidelines for the decision making between both treatments.

PATIENTS AND METHODS

The data of two randomized clinical trials for stage I and II breast cancer patients were pooled. The total number of patients in the study was 1,772, of whom 879 underwent breast conservation, and 893, modified radical mastectomy. Representative slides of the primary tumor were available for histopathologic review in 1,610 cases (91%).

RESULTS

There were 79 patients with local recurrence after breast-conservation and 80 after mastectomy, the 10-year rates being 10% (95% confidence interval [CI], 8% to 13%) and 9% (95% CI, 7% to 12%), respectively. Age no more than 35 years (compared with age >60: hazard ratio [HR], 9.24; 95% CI, 3.74 to 22.81) and an extensive intraductal component (HR, 2.52; 95% CI, 1.26 to 5.00) were significantly associated with an increased risk of local recurrence after breast-conserving therapy. Vascular invasion was predictive of the risk of local recurrence, irrespective of the type of primary treatment (P <.01). Tumor size, nodal status, high histologic grade, and vascular invasion were all highly significant predictors of distant disease after breast-conserving therapy and mastectomy (P <.01). Age no more than 35 years and microscopic involvement of the excision margin were additional independent predictors of distant disease after breast-conserving therapy (P <.01).

CONCLUSION

Age no more than 35 years and the presence of an extensive intraductal component are associated with an increased risk of local recurrence after breast-conserving therapy. Vascular invasion causes a higher risk of local recurrence after mastectomy as well as after breast-conserving therapy and should therefore not be used for deciding between the two treatments.

MR imaging of the breast in patients with invasive lobular carcinoma

OBJECTIVE

Our objective was to assess the usefulness of MR imaging in patients diagnosed with invasive lobular carcinoma of the breast.

MATERIALS AND METHODS

Between July 1993 and September 1999, 32 women (33 cases) diagnosed with pure invasive lobular carcinoma of the breast underwent contrast-enhanced MR imaging examination. One woman was excluded because of lack of follow-up. Correlation was made between the mammographic and sonographic findings, the MR imaging findings, and the final pathology results for the remaining 32 cases.

RESULTS

In 18 women who did not undergo excisional biopsy before the MR imaging, MR imaging showed more extensive tumor burden or the detection of the primary lesion that was occult on conventional imaging in seven (38.9%) of 18 women. In nine (50%) of 18 women, MR imaging performed equally as well as mammography and sonography. In one case (5.6%), MR imaging and mammography underestimated disease extent. In another patient (5.6%), MR imaging overestimated tumor burden, although mammography failed to show the cancer. In 14 patients who had excisional biopsy before the MR imaging, residual tumor was shown in eight women (57.1%) with extensive tumor or additional separate foci in five of the eight patients. In two cases (14.3%) that were interpreted as equivocal, residual tumor was shown in both cases on reexcision. In three cases (21.4%), the MR imaging was interpreted as negative, but microscopic tumor was shown around seroma on reexcision. False-positive enhancement was seen in one case (7.1%).

CONCLUSION

MR imaging showed more extensive tumor than conventional imaging and affected the clinical management in 16 (50%) of 32 patients with invasive lobular carcinoma.

Resection margin status in lumpectomy specimens of infiltrating lobular carcinoma

AIMS

To study the status of resection margins in specimens from patients with infiltrating lobular carcinoma (ILC) treated with lumpectomy.

MATERIALS AND METHODS

Sixty-six consecutive cases of ILC were compared with the same number of consecutive cases of infiltrating ductal carcinoma (IDC). All cases were treated with lumpectomy.

RESULTS

ILCs were divided into 42 cases of typical ILC, 15 variants of ILC (alveolar or solid types) and 9 cases of mixed ILC and IDC. These groups were associated with positive or close resection margins in 22 (52%), 5 (33%) and 3 (33%) cases, respectively. For the group of IDC with partial mastectomies, matched for patient's age and tumor size, positive or close resection margins were observed in 26%. ILCs, measuring less than 2 cm in greatest diameter and having low nuclear grade, had rates of positive or close margins comparable with those of IDC. Typical ILCs, measuring more than 2 cm in diameter, had rates of positive or close margins of 70%. All cases with a positive extensive intraductal component had positive margins. Furthermore, in all types of ILC, tumors with a high nuclear grade tended to be associated with a high rate of positive margins.

CONCLUSIONS

The status of resection margins in lumpectomy specimens for infiltrating lobular carcinoma is related to the extensive intraductal component status, tumor size and grade, and the presence of variants of ILC or mixed ILC and IDC. Most of these factors can be determined preoperatively by mammography and histopathological evaluation of breast core biopsies, therefore, aiding in planning the surgical strategy of mastectomy.

Histological determinants for different types of local recurrence after breast-conserving therapy of invasive breast cancer. Dutch Study Group on local Recurrence after Breast Conservation (BORST)

The purpose of this study was to determine which histological factors are associated with an increased risk for local recurrence in the breast after breast-conserving therapy for early breast cancer (TNM stage I and II) and whether risk patterns vary according to menopausal status and type of local recurrence. Through complete follow-up of the patients of eight regional radiation oncology departments, two cancer institutes and one surgical clinic in The Netherlands, 360 patients were identified with local recurrence in the breast after having received breast-conserving therapy (local tumour excision, axillary dissection and irradiation of the whole breast and a boost to the tumour bed) during the 1980s. For each case, two controls with a follow-up of similar duration without local recurrence were randomly selected. Histological slides of the primary tumour were reviewed. Among premenopausal patients the risk of recurrence for those younger than 35 years was significantly higher than that for premenopausal patients of 45 years or older (relative risk (RR) 2.9; 95% confidence interval (95% CI) 1.3-6.6, P < 0.05). The risk of recurrence at or near the site of the primary tumour was most significantly increased for patients with high grade extensive intraductal component (EIC) adjacent to the primary tumour (RR 4.1; 95% CI 1.7-9.8, P < 0.01). Microscopic margin involvement was an important risk indicator for diffuse recurrence and recurrence in the skin of the breast, especially in the presence of vascular invasion (RR 25; 95% CI 4.0-150, P < 0.001). To prevent local recurrence at or near the site of the primary tumour, local excision with a 1-2 cm margin of healthy tissue and a 15 Gy boost seemed adequate local treatment for patients with well differentiated EIC. In contrast, a wider surgical margin, a higher boost dose or mastectomy should be considered for patients with poorly differentiated EIC. Microscopic margin involvement in the presence of vascular invasion significantly increases the risk of diffuse recurrence or recurrence in the skin.

Conservative surgery and radiation therapy for invasive lobular carcinoma of the breast

BACKGROUND

There is debate as to whether infiltrating lobular carcinoma (ILC) can be effectively treated with breast conservative surgery (CS) and radiotherapy (RT) because of a perceived high risk of local recurrence. This retrospective study examined the outcome of patients with ILC treated by CS and RT.

METHODS

Between November 1979 and December 1994, 57 women with UICC Stage I or II ILC were treated by CS and RT at Westmead Hospital, New South Wales, Australia. The median age was 55 years (range 28-79). Twelve patients (21%) underwent a re-excision after initial CS. The final margins were clear for 43 patients (75.4%), positive (invasive or in situ) for nine patients (15.8%), and indeterminate for five patients (8.8%). All patients received whole-breast irradiation (45-50.4 Gy) usually supplemented by a boost (10-30 Gy). Fifty-three of 57 patients (93%) had their pathology reviewed at Westmead Hospital.

RESULTS

After a median follow up of 69 months (range 36-162) three patients (5.3%) developed a local recurrence. One of 43 patients (2.3%) with known clear margins developed a local recurrence compared with two of 14 patients (14.3%) with positive or indeterminate margins (P = NS). The 5- and 10-year rates of freedom from local recurrence were 96 and 93%, respectively. The 5-year disease-free survival was 85% (node-negative, 92%; node-positive, 66%). Overall survival was 94% at 5 years. No patient developed a contralateral breast cancer.

CONCLUSION

Patients with ILC can be effectively treated with CS and RT.

Reproducibility of a diagnosis of invasive lobular carcinoma

BACKGROUND AND OBJECTIVES

THE fact that invasive lobular carcinoma (ILC) is often multicentric has led to mastectomies being regularly performed for this disease in some settings. Reproducibility of the histological typing of breast cancer was investigated.

METHODS

Fifty slides from breast cancers were assessed individually by 10 pathologists from different institutions, whose findings were compared.

RESULTS

The extent of matching of the reported histological types between the various pairs of pathologists ranged between 28 and 88%. Agreement was better for pathologists with special experience in breast pathology. The kappa values for the exact histological type, for pure ILC and for the presence of an ILC component, were 0.23, 0.31, and 0.32, respectively (0.64, 0.43, and 0.46 for pathologists experienced in breast pathology).

CONCLUSIONS

The study demonstrates that there are equivocally interpreted tumors and the presence of ILC in the histological report should not serve as the sole determinant for the performance of mastectomy.