P4-11-02: Insulin-Like Growth Factor-1 (IGF-1), Insulin-Like Growth Factor Binding Protein-3 (IGFBP-3) and Lobule Type among Women in the Nurses' Health Study II (NHS II)

In a previous analysis of women enrolled in NHSII, we found that among women diagnosed with benign breast disease (BBD), those with predominant type 1/no type 3 lobules were at lower risk of subsequent breast cancer compared to women with other lobule types. Additionally, studies in animal models suggest that higher levels of IGF-1, a polypeptide hormone involved in the proliferation/differentiation of normal mammary epithelium, may inhibit involution of breast lobules. However, the interaction between IGF-1 levels and lobule types in determining breast cancer risk has not been previously evaluated. Therefore, we examined the association between IGF-1 levels and lobule type among women with BBD.

Methods: We conducted a cross-sectional study among 484 women in NHSII with biopsy-confirmed BBD between 1993–2001 who had blood samples available for determining levels of IGF-1 and IGFBP-3. A pathologist, blinded to exposure status, classified lobule type on biopsy slides according to the number of acini per lobule (type 1 < 12; type 2∼50; type 3∼80 acini). Lobule type was classified into (1) predominant type 1/no type 3 lobules or (2) other lobule types. Multivariate logistic models were used to assess the associations between plasma IGF-1, IGFBP-3, and IGF-1/IGFBP-3 levels with lobule type. Models were adjusted for age, IGF-1 batch and additional potential confounders in secondary analyses.

Results: In univariate analyses, older age at biopsy, higher body mass index, postmenopausal status, nulliparity, and lower IGF-1 levels were associated with predominant type1/no type 3 lobules (p<0.05). In multivariate logistic models adjusting for age, higher IGF-1 levels were associated with a decreased risk of predominant type 1/no type 3 lobules (OR quartile 4 vs. quartile 1 = 0.35, 95%CI: 0.15−0.81). Greater IGF-1/IGFBP-3 ratio was also associated with a decreased risk of predominant type1/no type 3 lobules (OR quartile 4 vs. quartile 1 = 0.24, 95%CI: 0.10−0.57).

Defining breast cancer prognosis based on molecular phenotypes: results from a large cohort study

Abstract #1068

Aim
 Identification at the molecular level of breast cancers sub-types associated with different clinical outcomes would be of great value to help individualize therapeutic strategies and, in turn, improve survival. With large sample size, long follow-up, and geographical spread of the population any results derived from analysis of the Nurses' Health Study (NHS) data set may be more generalizable to the U.S population. Thus the purpose of this study was to define the survival outcomes associated with distinct molecular phenotypes of invasive breast cancer in women identified from the NHS.
 Methods
 2013 women enrolled in the NHS (1976-1996) with invasive non-metastatic breast cancer whose breast tumor samples were available for inclusion in tissue microarrays and subsequent immunohistochemical (IHC) analysis form the study population. Tumors were classified into one of 5 categories based on results of IHC assays for estrogen receptor (ER), progesterone receptor (PR), HER2, cytokeratin (CK) 5/6, and epidermal growth factor receptor (EGFR) as follows: 1) Luminal-A (ER and/or PR +ve and HER2 -ve), 2) Luminal-B (ER and/or PR +ve and HER2 +ve), 3) HER2 subtype (HER2 +ve with both ER and PR -ve), 4) Basal-like (-ve for ER, PR and HER2 and +ve for either CK5/6 and/or EGFR), 5) unclassifiable (-ve for all markers). Overall survival (OS), breast-cancer-specific survival (BCS) and recurrence-free survival (RFS) were estimated using the Kaplan-Meir product limit method and compared across groups using the log rank statistic. Cox-proportional hazards models were fitted to determine the association of molecular phenotype with survival outcomes after adjusting for age at diagnosis, stage, lymph nodes, tumor size, grade and body mass index at diagnosis.
 Results
 Median age at diagnosis was 57 years (34 – 75 years) with a median follow-up of 14 years. 1490 (74%) tumors were classified as luminal-A, 99 (4.9%) were classified as luminal-B, 106 (5.27%) were of HER2 subtype, 219 (10.9%) were classified as basal-like and 99 (4.9%) tumors were unclassifiable.726 (36%) patients had died of any cause, 433 (21.5%) had died of a breast cancer related event, and 459 (22.8%) experienced a recurrence. Five-year BCS for patients with luminal-A, luminal-B, HER2 , basal-like and unclassifiable tumors was 94%, 82%, 73%, 82% and 75% respectively (p<0.001). In the fully adjusted multivariable model compared to patients with luminal-A tumors patients with luminal-B (HR 1.73, 95% 1.18-2.53), HER2 (HR 1.39, 95% CI 0.97-1.20), basal-like (HR 1.50, 95% 1.32-1.20) and unclassifiable (HR 1.89, 95% CI 1.30-2.74) tumors had lower BCS. Similar trends were observed for OS and RFS.
 Conclusions
 Compared to women who have luminal-A tumors those with luminal-B, HER2 subtype, basal-like and unclassifiable tumors had a worse prognosis. A fifth, unclassifiable sub-group was identified that has survival outcomes similar to and may represent a subtype of basal-like tumors.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1068.

Fine-Needle Aspiration Biopsy of Nonpalpable Breast Lesions in a Multicenter Clinical Trial: Results from the Radiologic Diagnostic Oncology Group V

PURPOSE

To determine the diagnostic accuracy of ultrasonographically (US) and stereotactically guided fine-needle aspiration biopsy (FNAB) in the diagnosis of nonpalpable breast lesions.

MATERIALS AND METHODS

At 18 institutions, 442 women who underwent 22-25-gauge imaging-guided FNAB were enrolled. Definitive surgical, core-needle biopsy, and/or follow-up information was available for 423 (95.7%) of these women. The reference standard was established from additional clinical and imaging information for an additional six (1.4%) women who did not undergo further histopathologic evaluation. The FNAB protocol was standardized at all institutions, and all specimens were reread by one of two expert cytopathologists.

RESULTS

When insufficient samples were included in the analysis and classified as positive, the sensitivity and specificity of FNAB were 85%-88% and 55.6%-90.5%, respectively; accuracy ranged from 62.2% to 89.2%. The diagnostic accuracy of FNAB was significantly better for detection of masses than for detection of calcifications (67.3% vs. 53.8%, P =.006) and with US guidance than with stereotactic guidance (77.2% vs. 58.9%; P =.002).

CONCLUSION

FNAB of nonpalpable breast lesions has limited value given the high insufficient sample rate and greater diagnostic accuracy of other interventions, including core-needle biopsy and needle-localized open surgical biopsy.

Reovirus binding to cell surface sialic acid potentiates virus-induced apoptosis

Reovirus induces apoptosis in cultured cells and in vivo. Genetic studies indicate that the efficiency with which reovirus strains induce apoptosis is determined by the viral S1 gene, which encodes attachment protein sigma1. However, the biochemical properties of sigma1 that influence apoptosis induction are unknown. To determine whether the capacity of sigma1 to bind cell surface sialic acid determines the magnitude of the apoptotic response, we used isogenic reovirus mutants that differ in the capacity to engage sialic acid. We found that T3SA+, a virus capable of binding sialic acid, induces high levels of apoptosis in both HeLa cells and L cells. In contrast, non-sialic-acid-binding strain T3SA- induces little or no apoptosis in these cell types. Differences in the capacity of T3SA- and T3SA+ to induce apoptosis are not due to differences in viral protein synthesis or production of viral progeny. Removal of cell surface sialic acid with neuraminidase abolishes the capacity of T3SA+ to induce apoptosis. Similarly, incubation of T3SA+ with sialyllactose, a trisaccharide comprised of lactose and sialic acid, blocks apoptosis. These findings demonstrate that reovirus binding to cell surface sialic acid is a critical requirement for the efficient induction of apoptosis and suggest that virus receptor utilization plays an important role in regulating cell death.

Pathologic features of breast cancers in women with previous benign breast disease

To compare pathologic features of the cancers arising after different types of benign breast disease (BBD), we reviewed the invasive breast cancer slides of 169 women with a previous benign biopsy result. Lesions were categorized previously as nonproliferative, proliferative without atypia, or atypical hyperplasia. Pathologic features of the cancers were evaluated without knowledge of the previous BBD category. Estrogen and progesterone receptor immunohistochemistry was performed on available tissue blocks. The median times between a benign result and cancer were 100, 124, and 92 months for women with nonproliferative lesions, proliferative lesions without atypia, and atypical hyperplasia, respectively. Cancers in the 3 groups did not differ significantly in tumor size, axillary lymph node status, or histologic grade, and there was no significant difference in the distribution of histologic types of breast cancer. Lymphatic vessel invasion, extensive intraductal component, and hormone receptor status did not differ among BBD categories. The pathologic features of breast cancers that develop in women with a previous benign biopsy result do not vary according to the histologic category of the previous BBD.

Junction adhesion molecule is a receptor for reovirus

Virus attachment to cells plays an essential role in viral tropism and disease. Reovirus serotypes 1 and 3 differ in the capacity to target distinct cell types in the murine nervous system and in the efficiency to induce apoptosis. The binding of viral attachment protein sigma1 to unidentified receptors controls these phenotypes. We used expression cloning to identify junction adhesion molecule (JAM), an integral tight junction protein, as a reovirus receptor. JAM binds directly to sigma1 and permits reovirus infection of nonpermissive cells. Ligation of JAM is required for reovirus-induced activation of NF-kappaB and apoptosis. Thus, reovirus interaction with cell-surface receptors is a critical determinant of both cell-type specific tropism and virus-induced intracellular signaling events that culminate in cell death.

Utilization of sialic acid as a coreceptor enhances reovirus attachment by multistep adhesion strengthening

Many serotype 3 reoviruses bind to two different host cell molecules, sialic acid and an unidentified protein, using discrete receptor-binding domains in viral attachment protein, final sigma1. To determine mechanisms by which these receptor-binding events cooperate to mediate cell attachment, we generated isogenic reovirus strains that differ in the capacity to bind sialic acid. Strain SA+, but not SA-, bound specifically to sialic acid on a biosensor chip with nanomolar avidity. SA+ displayed 5-fold higher avidity for HeLa cells when compared with SA-, although both strains recognized the same proteinaceous receptor. Increased avidity of SA+ binding was mediated by increased k(on). Neuraminidase treatment to remove cell-surface sialic acid decreased the k(on) of SA+ to that of SA-. Increased k(on) of SA+ enhanced an infectious attachment process, since SA+ was 50-100-fold more efficient than SA- at infecting HeLa cells in a kinetic fluorescent focus assay. Sialic acid binding was operant early during SA+ attachment, since the capacity of soluble sialyllactose to inhibit infection decreased rapidly during the first 20 min of adsorption. These results indicate that reovirus binding to sialic acid enhances virus infection through adhesion of virus to the cell surface where access to a proteinaceous receptor is thermodynamically favored.

Diagnostic accuracy of 99mTc-sestamibi breast imaging: multicenter trial results

Although mammography is well established as a first-line tool for breast cancer screening and detection, efforts to develop complementary procedures continue. Observation of 99mTc-sestamibi tumor uptake provided the impetus for its evaluation as an adjunctive technique. This trial's objectives were to determine in a multicenter trial the diagnostic accuracy of 99mTc-sestamibi in women with suspected breast cancer and to investigate factors influencing diagnostic accuracy.

METHODS

Our multicenter trial enrolled 673 women (387 with nonpalpable abnormalities; 286 with palpable abnormalities) scheduled for excisional biopsy or mastectomy. Blinded and unblinded interpretations of scintigraphic images were compared with core laboratory established histopathologic diagnoses to define the diagnostic accuracy of 99mTc-sestamibi breast imaging.

RESULTS

Blinded readers' diagnostic accuracy was 78%-81%. Inter-reader agreement was excellent, ranging from 95% to 100% (kappa = 0.82-0.99). Overall institutional sensitivity and specificity for 99mTc-sestamibi breast imaging were 75.4% and 82.7%, respectively. In this population with a 40.1% disease prevalence, the positive predictive value was 74.5% and the negative predictive value was 83.4%. The negative predictive value was 94% in patients with a 40% or lower mammographic likelihood of breast cancer. Sensitivity was higher for palpable abnormalities; specificity was higher for nonpalpable abnormalities. Sensitivity was decreased for tumors <1 cm in largest dimension but appeared not to be affected by patient's age.

CONCLUSION

As an adjunct to current procedures, 99mTc-sestamibi breast imaging may contribute to patient management decisions in selected populations, including women with dense breasts, mammographically indeterminate lesions >1 cm, and palpable abnormalities.

Biopsy confirmed benign breast disease, postmenopausal use of exogenous female hormones, and breast carcinoma risk

BACKGROUND

A history of proliferative benign breast disease has been shown to increase the risk of developing breast carcinoma, but, to the authors' knowledge, how postmenopausal exogenous female hormone use, in general, has affected breast carcinoma risk among women with a history of proliferative breast disease with or without atypia has not been well established.

METHODS

In the current case-control study, nested within the Nurses' Health Study, benign breast biopsy slides of 133 postmenopausal breast carcinoma cases and 610 controls with a history of benign breast disease, were reviewed. Reviewers had no knowledge of case status.

RESULTS

Women with proliferative disease without atypia had a relative risk for postmenopausal breast carcinoma of 1.8 (95%, confidence interval [CI]: 1.1 to 2.8), and women with atypical hyperplasia had a relative risk of 3.6 (95%, CI: 2.0 to 6.4) compared with women who had nonproliferative benign histology. Neither current postmenopausal use of exogenous female hormones nor long term use for 5 or more years further increased the risk of breast carcinoma in the study population beyond that already associated with their benign histology.

CONCLUSIONS

Women who had proliferative benign breast disease, with or without atypia, were at moderately to substantially increased risk of developing postmenopausal breast carcinoma compared with women who had nonproliferative benign conditions. In the current study, postmenopausal exogenous female hormone use in general did not further increase the breast carcinoma risk for women with proliferative benign breast disease. However, the analysis did not exclude the possibility of increased risk with a particular hormone combination or dosage.

Reovirus-induced G(2)/M cell cycle arrest requires sigma1s and occurs in the absence of apoptosis

Serotype-specific differences in the capacity of reovirus strains to inhibit proliferation of murine L929 cells correlate with the capacity to induce apoptosis. The prototype serotype 3 reovirus strains Abney (T3A) and Dearing (T3D) inhibit cellular proliferation and induce apoptosis to a greater extent than the prototype serotype 1 reovirus strain Lang (T1L). We now show that reovirus-induced inhibition of cellular proliferation results from a G(2)/M cell cycle arrest. Using T1L x T3D reassortant viruses, we found that strain-specific differences in the capacity to induce G(2)/M arrest, like the differences in the capacity to induce apoptosis, are determined by the viral S1 gene. The S1 gene is bicistronic, encoding the viral attachment protein sigma1 and the nonstructural protein sigma1s. A sigma1s-deficient reovirus strain, T3C84-MA, fails to induce G(2)/M arrest, yet retains the capacity to induce apoptosis, indicating that sigma1s is required for reovirus-induced G(2)/M arrest. Expression of sigma1s in C127 cells increases the percentage of cells in the G(2)/M phase of the cell cycle, supporting a role for this protein in reovirus-induced G(2)/M arrest. Inhibition of reovirus-induced apoptosis failed to prevent virus-induced G(2)/M arrest, indicating that G(2)/M arrest is not the result of apoptosis related DNA damage and suggests that these two processes occur through distinct pathways.

Is radiation alone adequate treatment to the axilla for patients with limited axillary surgery? Implications for treatment after a positive sentinel node biopsy

PURPOSE

To estimate the possible efficacy of axillary radiation therapy (AXRT) following a positive sentinel node biopsy (SNB), we evaluated the risk of regional nodal failure (RNF) for patients with clinical Stage I or II, clinically node-negative invasive breast cancer treated with either no dissection or a limited dissection (LD) defined as removal of 5 nodes or less followed by AXRT.

MATERIALS AND METHODS

From 1978 to 1987, 292 patients underwent AXRT in the absence of axillary dissection; 126 underwent AXRT following LD. The median dose to the axilla was 46 Gy. The median dose to the supraclavicular fossa was 45 Gy. Among patients found to have positive nodes on LD, adjuvant chemotherapy and tamoxifen were administered to 81% and 7% of subjects, respectively. All patients had potential 8-year follow-up.

RESULTS

Six of the 418 patients (1. 4%) developed RNF as a first site of failure within 8 years. Among these 6 patients (1.4%) with RNF as the first site of failure, 4 had simultaneous distant and regional recurrences; and 2 had isolated axillary failures. Three of the 292 patients (1%) with no axillary dissection, none of 84 patients with pathologically negative nodes and 3 of 42 patients (7%) with pathologically involved nodes had RNF as a first site of failure. Radiation pneumonitis developed in 5 patients (1.2%), brachial plexopathy in 5 (1.2%) and arm edema in 4 (1.2%). In all cases, radiation pneumonitis and brachial plexopathy were transient.

CONCLUSION

These results imply that AXRT may be an effective and safe alternative to completion dissection for treatment of the axilla following a positive SNB. Further studies comparing these two options in specific patient subgroups are needed.

The relationship between lymphatic vessell invasion, tumor size, and pathologic nodal status: can we predict who can avoid a third field in the absence of axillary dissection?

PURPOSE

Tangential (2-field) radiation therapy to the breast and lower axilla is typically used in our institution for treating patients with early-stage breast cancer who have 0-3 positive axillary nodes, as determined by axillary dissection, whereas a third supraclavicular/axillary field is added for patients with 4 or more positive nodes. However, dissection may result in complications and added expense. We, therefore, assessed whether clinical or pathologic factors of the primary tumor could reliably predict, in the absence of an axillary dissection, which patients with clinically negative axillary nodes have such limited pathologic nodal involvement that they might be effectively treated with only tangential fields. This would eliminate both the complications of axillary dissection and the added complexity and potential morbidity of a supraclavicular/axillary field.

METHODS AND MATERIALS

In this study, 722 women with clinical Stage I or II unilateral invasive breast cancer of infiltrating ductal histology, with clinically negative axillary nodes, at least 6 lymph nodes recovered on axillary dissection, and central pathology review were treated with breast-conserving therapy from 1968 to 1987. Pathologic nodal status was assessed in relation to clinical T stage, the presence of lymphatic vessel invasion (LVI), age, histologic grade, and the location of the primary tumor.

RESULTS

LVI, T stage, and tumor location were each significantly correlated with nodal status on univariate analysis. Ninety-seven percent of LVI-negative patients had 0-3 positive axillary nodes compared to 87% of LVI-positive patients. There was no association between T stage and extent of axillary involvement within LVI-negative and LVI-positive subgroups. In a logistic regression model, only LVI remained a significant predictor of having 4 or more positive nodes, although tumor size was of borderline significance. The odds ratio for LVI (positive vs. negative) as a predictor of having 4 or more positive nodes was 3.9 (95% CI, 2.0-7.6).

CONCLUSION

For patients with clinical T1-2, N0, infiltrating ductal carcinomas, the presence of LVI is predictive of having 4 or more positive axillary nodes. Only 3% of patients with clinical T1-2, N0, LVI-negative breast cancers had 4 or more positive nodes on axillary dissection. Such patients may be reasonable candidates for treatment with tangential radiation fields in the absence of axillary dissection.

Prognostic factors in breast cancer. College of American Pathologists Consensus Statement 1999

BACKGROUND

Under the auspices of the College of American Pathologists, a multidisciplinary group of clinicians, pathologists, and statisticians considered prognostic and predictive factors in breast cancer and stratified them into categories reflecting the strength of published evidence.

MATERIALS AND METHODS

Factors were ranked according to previously established College of American Pathologists categorical rankings: category I, factors proven to be of prognostic import and useful in clinical patient management; category II, factors that had been extensively studied biologically and clinically, but whose import remains to be validated in statistically robust studies; and category III, all other factors not sufficiently studied to demonstrate their prognostic value. Factors in categories I and II were considered with respect to variations in methods of analysis, interpretation of findings, reporting of data, and statistical evaluation. For each factor, detailed recommendations for improvement were made. Recommendations were based on the following aims: (1) increasing uniformity and completeness of pathologic evaluation of tumor specimens, (2) enhancing the quality of data collected about existing prognostic factors, and (3) improving patient care.

RESULTS AND CONCLUSIONS

Factors ranked in category I included TNM staging information, histologic grade, histologic type, mitotic figure counts, and hormone receptor status. Category II factors included c-erbB-2 (Her2-neu), proliferation markers, lymphatic and vascular channel invasion, and p53. Factors in category III included DNA ploidy analysis, microvessel density, epidermal growth factor receptor, transforming growth factor-alpha, bcl-2, pS2, and cathepsin D. This report constitutes a detailed outline of the findings and recommendations of the consensus conference group, organized according to structural guidelines as defined.

Reovirus-induced apoptosis requires activation of transcription factor NF-kappaB

Reovirus infection induces apoptosis in cultured cells and in vivo. To identify host cell factors that mediate this response, we investigated whether reovirus infection alters the activation state of the transcription factor nuclear factor kappa B (NF-kappaB). As determined in electrophoretic mobility shift assays, reovirus infection of HeLa cells leads to nuclear translocation of NF-kappaB complexes containing Rel family members p50 and p65. Reovirus-induced activation of NF-kappaB DNA-binding activity correlated with the onset of NF-kappaB-directed transcription in reporter gene assays. Three independent lines of evidence indicate that this functional form of NF-kappaB is required for reovirus-induced apoptosis. First, treatment of reovirus-infected HeLa cells with a proteasome inhibitor prevents NF-kappaB activation following infection and substantially diminishes reovirus-induced apoptosis. Second, transient expression of a dominant-negative form of IkappaB that constitutively represses NF-kappaB activation significantly reduces levels of apoptosis triggered by reovirus infection. Third, mutant cell lines deficient for either the p50 or p65 subunits of NF-kappaB are resistant to reovirus-induced apoptosis compared with cells expressing an intact NF-kappaB signaling pathway. These findings indicate that NF-kappaB plays a significant role in the mechanism by which reovirus induces apoptosis in susceptible host cells.

The relation between the presence and extent of lobular carcinoma in situ and the risk of local recurrence for patients with infiltrating carcinoma of the breast treated with conservative surgery and radiation therapy

BACKGROUND

When found in an otherwise benign biopsy, lobular carcinoma in situ (LCIS) has been associated with an increased risk of development of a subsequent invasive breast carcinoma. However, the association between LCIS and the risk of subsequent local recurrence in patients with infiltrating carcinoma treated with conservative surgery and radiation therapy has received relatively little attention.

METHODS

Between 1968 and 1986, 1625 patients with clinical Stage I-II invasive breast carcinoma were treated at the Joint Center for Radiation Therapy at Harvard Medical School with breast-conserving surgery (CS) and radiation therapy (RT) to a total dose to the primary site of > or =60 grays. Analysis was limited to 1181 patients with infiltrating ductal carcinoma, infiltrating lobular carcinoma, or infiltrating carcinoma with mixed ductal and lobular features who, on review of their histologic slides, had sufficient normal tissue adjacent to the tumor to evaluate for the presence of LCIS and also had a minimum potential follow-up time of 8 years. The median follow-up time was 161 months.

RESULTS

One hundred thirty-seven patients (12%) had LCIS either within the tumor or in the macroscopically normal adjacent tissue. The 8-year crude risk of recurrence was not significantly increased for patients with LCIS associated with invasive ductal, invasive lobular, or mixed ductal and lobular carcinoma. Among the 119 patients with associated LCIS adjacent to the tumor, the 8-year rate of local recurrence was 13%, compared with 12% for the 1062 patients without associated LCIS. For the 70 patients with moderate or marked LCIS adjacent to the tumor, the 8-year rate of local recurrence was 13%. The extent of LCIS did not affect the risk of recurrence. The risks of contralateral disease and of distant failure were similarly not affected by the presence or extent of LCIS.

CONCLUSIONS

Breast-conserving therapy involving limited surgery and radiation therapy is an appropriate method of treating patients with invasive breast carcinoma with or without associated LCIS. Neither the presence nor the extent of LCIS should influence management decisions regarding patients with invasive breast carcinoma. [See editorial counterpoint and reply to counterpoint on pages 978-81 and 982-3, this issue.]

The influence of infiltrating lobular carcinoma on the outcome of patients treated with breast-conserving surgery and radiation therapy

BACKGROUND

The role of conservative surgery and radiation therapy (CS and RT) in the treatment of patients with infiltrating ductal carcinoma is well established. However, the efficacy of CS and RT for patients with infiltrating lobular carcinoma is less well documented. The goal of this study was to examine treatment outcome after CS and RT for patients with infiltrating lobular carcinoma and to compare the results to those of patients with infiltrating ductal carcinoma and patients with mixed ductal-lobular histology.

METHODS

Between 1970 and 1986, 1624 patients with Stage I or II invasive breast cancer were treated with CS and RT consisting of a complete gross excision of the tumor and > or = 6000 cGy to the primary site. Slides were available for review for 1337 of these patients (82%). Of these, 93 had infiltrating lobular carcinoma, 1089 had infiltrating ductal carcinoma, and 59 had tumors with mixed ductal and lobular features; these patients constitute the study population. The median follow-up time for surviving patients was 133 months. A comprehensive list of clinical and pathologic features was evaluated for all patients. Additional histologic features assessed for patients with infiltrating lobular carcinoma included histologic subtype, multifocal invasion, stromal desmoplasia, and the presence of signet ring cells.

RESULTS

Five and 10-year crude results by site of first failure were similar for patients with infiltrating lobular, infiltrating ductal, and mixed histology. In particular, the 10-year crude local recurrence rates were 15%, 13%, and 13% for patients with infiltrating lobular, infiltrating ductal, and mixed histology, respectively. Ten-year distant/regional recurrence rates were 22%, 23%, and 20% for the three groups, respectively. In addition, the 10-year crude contralateral breast cancer rates were 4%, 13% and 6% for patients with infiltrating lobular, infiltrating ductal and mixed histology, respectively. In a multiple regression analysis which included established prognostic factors, histologic type was not significantly associated with either survival or time to recurrence.

CONCLUSIONS

Patients with infiltrating lobular carcinoma have a similar outcome following CS and RT to patients with infiltrating ductal carcinoma and to patients with tumors that have mixed ductal and lobular features. We conclude that the presence of infiltrating lobular histology should not influence decisions regarding local therapy in patients with Stage I and II breast cancer.

The significance of extracapsular extension of axillary lymph node metastases in early-stage breast cancer

PURPOSE

To investigate if extracapsular extension (ECE) of axillary lymph node metastases predicts for a decreased rate of disease-free survival or an increased rate of regional recurrence of breast carcinoma.

METHODS

The study population consisted of 368 patients with T1 or T2 breast cancer and pathologically-positive lymph nodes treated with breast-conserving therapy between 1968 and 1986. The median number of sampled lymph nodes was 10. Median follow-up time for the surviving patients was 139 months (range 70-244). Twenty percent of the patients were treated with supraclavicular RT, and 64% received both axillary and supraclavicular RT, with a median dose to the nodes of 45 Gy. The following factors were evaluated: presence of ECE, number of sampled lymph nodes (LN), number of involved LN, size of primary tumor, histologic grade of tumor, presence of lymphatic vessel invasion (LVI), presence of an extensive intraductal component (EIC), radiation dose, use of adjuvant chemotherapy, and age of patient. Recurrences were reported as the 5-year crude sites of first failure, and were divided into breast recurrences (LR), regional nodal failure (RNF, defined as isolated axillary, supraclavicular, or internal mammary recurrence), and distant metastases (DM).

RESULTS

One hundred twenty-two patients (33%) had ECE and 246 patients did not. The median number of LN with ECE was 1 (range 1-10) and 20% of patients had ECE in > or =4 LN. Patients with ECE tended to be older (median age 51 vs. 47, p = 0.01), and had a higher number of involved LN (median 3 vs. 2, p = 0.005) than patients without ECE. Forty-three percent of patients with ECE had > or =4 involved LN compared to 15% of patients without ECE (p<0.0001). Models of ECE and the above factors revealed no significant correlation between ECE and either disease-free or overall survival. There was no statistically significant increase in local, regional nodal, or distant failures in patients with ECE as compared to patients without ECE.

CONCLUSION

In this population of patients with nodal involvement, the presence of ECE correlates with the number of involved LN but does not appear to add predictive power to models of local, regional, or distant recurrence when the number of positive LN is included.

Factors associated with regional nodal failure in patients with early stage breast cancer with 0-3 positive axillary nodes following tangential irradiation alone

PURPOSE

Recent randomized trials have suggested that improved local-regional control after radiation therapy significantly increases survival for breast cancer patients with positive axillary nodes treated with adjuvant systemic therapy (1, 2). It has been our policy to use a third radiation field only in patients with 4 or more positive nodes. The purpose of this study was to assess whether there are any clinical or pathologic factors associated with an increased risk of regional nodal failure (RNF) in patients with 0-3 positive nodes treated with tangential radiotherapy (RT) alone with or without systemic therapy.

METHODS AND MATERIALS

We retrospectively analyzed the incidence of RNF for 691 patients with clinical Stage I or II invasive breast cancer treated with complete gross excision of the primary tumor and tangential RT alone between 1978-87; 12% also received systemic therapy. All had 0-3 positive nodes on axillary dissection that had histologic examination of > or =6 nodes, and all had potential 8-year follow-up. The median number of axillary nodes removed was 11 (range 6-36). RNF was defined as any recurrence in ipsilateral axillary, internal mammary, supraclavicular, or infraclavicular nodes in the absence of recurrence in the breast, with or without simultaneous distant metastasis. Crude rates for first sites of failure within the first 8 years after treatment were calculated. A polychotomous logistic regression was used to identify factors prognostic for RNF and other sites of first failure.

RESULTS

Within 8 years, RNF was the first site of failure for 27 patients for a crude 8-year rate of 3.9%. Isolated axillary failure occurred in 8 patients (1.2%). Isolated supraclavicular and/or infraclavicular failure occurred in 5 (1.3%) and 3 (0.4%) patients, respectively. Isolated internal mammary node failure occurred in 2 patients (0.3%). A polychotomous logistic regression model of first site of failure (local failure, regional nodal, distant/ opposite breast, dead without recurrence, no evidence of disease) within 8 years found age <50 years, moderate or marked necrosis, size greater than 1 cm, and presence of an extensive intraductal component (EIC) to be significantly correlated with site of first failure, but only the last two were associated with a significantly larger relative risk of RNF versus being no evidence of disease at 8 years. The incidence of RNF was 0.7% for patients with tumors < or =1 cm compared to 5.7% among patients with larger tumors. Among patients with EIC-positive tumors the incidence of RNF was 7.6% compared to 3.1% among those whose tumors were EIC-negative.

CONCLUSIONS

Although the incidence of RNF has been shown to be somewhat higher in patients with tumors measuring greater than 1 cm and those with an EIC, RNF is uncommon among all subsets of patients with negative or 1-3 positive lymph nodes treated with conservative surgery, axillary dissection, and only tangential RT fields. Therefore, giving only tangential RT (without a separate nodal field) appears generally acceptable for patients with 0-3 positive nodes.

Association of age and reproductive factors with benign breast tissue composition

Reproductive breast cancer risk factors are hypothesized to act by increasing exposure of the breast to endogenous estrogens, but few studies have quantitatively examined the association of these risk factors with breast tissue composition. This study is part of a case-control study of breast histological characteristics and breast cancer risk, nested within the Nurses' Health Study, a prospective study of 121,700 registered nurses. We studied 300 women who had not been diagnosed with breast cancer, but for whom we obtained slides from a prior benign breast biopsy. We used a computer-assisted image analysis technique to assess the proportion of epithelial and fibrous stromal tissue on benign breast biopsy slides, excluding obvious mass lesions. Mean epithelial proportion was 5.3% (0.1-23%), and mean stromal proportion was 58.7% (3-93%). Women with proliferative breast disease without atypia had higher epithelial and stromal proportions than women with nonproliferative breast disease (P < 0.001). Postmenopausal women had a lower epithelial proportion (P = 0.01), and increasing age at biopsy was associated with decreasing stromal proportion among postmenopausal parous women (P = 0.004). Among premenopausal women, increasing years since last birth was associated with lower epithelial proportion (P < 0.001). Other reproductive risk factors were not independently associated with epithelial or stromal proportion. Epithelial and stromal breast tissue were associated with different factors with the exception of proliferative breast disease, which was associated with an increase in both epithelial and stromal proportion. The quantitative measurement of epithelial and stromal proportion may be useful for measuring changes in breast composition.

Structural basis of activation and GTP hydrolysis in Rab proteins

BACKGROUND

Rab proteins comprise a large family of GTPases that regulate vesicle trafficking. Despite conservation of critical residues involved in nucleotide binding and hydrolysis, Rab proteins exhibit low sequence identity with other GTPases, and the structural basis for Rab function remains poorly characterized.

RESULTS

The 2. 0 A crystal structure of GppNHp-bound Rab3A reveals the structural determinants that stabilize the active conformation and regulate GTPase activity. The active conformation is stabilized by extensive hydrophobic contacts between the switch I and switch II regions. Serine residues in the phosphate-binding loop (P loop) and switch I region mediate unexpected interactions with the gamma phosphate of GTP that have not been observed in previous GTPase structures. Residues implicated in the interaction with effectors and regulatory factors map to a common face of the protein. The electrostatic potential at the surface of Rab3A indicates a non-uniform distribution of charged and nonpolar residues.

CONCLUSIONS

The major structural determinants of the active conformation involve residues that are conserved throughout the Rab family, indicating a common mode of activation. Novel interactions with the gamma phosphate impose stereochemical constraints on the mechanism of GTP hydrolysis and provide a structural explanation for the large variation of GTPase activity within the Rab family. An asymmetric distribution of charged and nonpolar residues suggests a plausible orientation with respect to vesicle membranes, positioning predominantly hydrophobic surfaces for interaction with membrane-associated effectors and regulatory factors. Thus, the structure of Rab3A establishes a framework for understanding the molecular mechanisms underlying the function of Rab GTPases.

Radial scars in benign breast-biopsy specimens and the risk of breast cancer

BACKGROUND

Radial scars are benign breast lesions of uncertain clinical significance. In particular, it is not known whether these lesions alter the risk of breast cancer in women with benign breast disease. We conducted a case-control study of women who had benign breast lesions with or without radial scars.

METHODS

We reviewed benign breast-biopsy specimens from 1396 women enrolled in the Nurses' Health Study, including 255 women in whom breast cancer subsequently developed and 1141 women without subsequent breast cancer (controls). The controls were matched to the women with subsequent breast cancer according to age and the year when the benign lesion was identified. The median follow-up after biopsy of the benign lesions was 12 years.

RESULTS

Radial scars were identified in biopsy specimens from 99 women (7.1 percent). Most biopsy specimens with radial scars had only one radial scar (60.6 percent), and they tended to be incidental microscopical findings (median size, 4.0 mm). The women with radial scars had a risk of breast cancer that was almost twice the risk of the women without scars, regardless of the histologic type of benign breast disease (relative risk, 1.8; 95 percent confidence interval, 1.1 to 2.9). Among women who had proliferative disease without atypia as compared with women who had nonproliferative disease, the relative risk of breast cancer was 3.0 (95 percent confidence interval, 1.7 to 5.5) for those with radial scars and 1.5 (95 percent confidence interval, 1.1 to 2.1) for those without radial scars. Among women with atypical hyperplasia as compared with women with nonproliferative disease, the relative risk of breast cancer was 5.8 (95 percent confidence interval, 2.7 to 12.7) for those with radial scars and 3.8 (95 percent confidence interval, 2.4 to 5.9) for those without radial scars.

CONCLUSIONS

Radial scars are an independent histologic risk factor for breast cancer.

Correlation of tumor size and axillary lymph node involvement with prognosis in patients with T1 breast carcinoma

BACKGROUND

The prognosis of patients with T1 breast carcinoma remains controversial. Some studies have shown a low risk of lymph node metastasis and distant failure whereas others have not, possibly due to differences in the definition of tumor size. In this study, the authors assessed the relation between macroscopic tumor size, microscopic invasive tumor size, axillary lymph node involvement, and prognosis in a group of patients with clinically lymph node negative disease.

METHODS

Between 1968 and 1986, 1865 women with American Joint Committee on Cancer clinical Stage I or II infiltrating carcinoma of the breast were treated at the Joint Center for Radiation Therapy with conservative surgery and radiation therapy. The study population was limited to 118 patients with clinically negative axillary lymph nodes for whom the macroscopic pathologic tumor size was identified unambiguously as being < or = 2.0 cm, who underwent an axillary lymph node dissection with at least 6 lymph nodes sampled, and for whom the microscopic size of the invasive component could be determined. The median follow-up time for surviving patients was 134 months (range, 90-208 months). No patients with pathologically negative axillary lymph nodes received systemic therapy.

RESULTS

Macroscopic and microscopic tumor sizes differed by > 5 mm in 17 patients (14%), by 3-5 mm in 24 patients (20%), and by < or = 2 mm in 77 patients (65%). The macroscopic tumor size was smaller than the microscopic size in 37 patients (31%), larger in 55 patients (47%), and equal in 26 patients (22%). Pathologic axillary lymph node involvement was present in 21% of all patients. The risk of lymph node involvement was not significantly different for those patients with tumors < or = 1 cm compared with patients with tumors > or = 1.1 cm, regardless of whether tumor size was measured by macroscopic or microscopic examination. The 10-year actuarial rate of freedom from distant recurrence (FFDR) was 91% for lymph node negative patients with macroscopic tumors measuring < or = 1.0 cm compared with 77% for patients with macroscopic tumors measuring > or = 1.1 cm (P = 0.07). When measured microscopically, the rates were 96% and 72%, respectively (P = 0.001).

CONCLUSIONS

There often is a discrepancy between microscopic tumor size and macroscopic tumor size. T1 tumors have a substantial risk of axillary lymph node metastasis whether measured macroscopically or microscopically. Among those patients with pathologic lymph node negative tumors who are not treated with systemic adjuvant therapy, microscopic invasive tumor size is a better predictor of 10-year FFDR than macroscopic tumor size. There is a substantial risk of distant failure for patients with tumors whose invasive component microscopically measure > or = 1.1 cm, whereas the prognosis for patients with tumors that microscopically measured < or = 1 cm is excellent. These results suggest that the microscopic size of the invasive component of breast carcinomas < or = 2.0 cm routinely should be reported.

Columnar alteration with prominent apical snouts and secretions: a spectrum of changes frequently present in breast biopsies performed for microcalcifications

We have noted in breast biopsies performed for microcalcifications a spectrum of lesions in the terminal duct lobular unit (TDLU) characterized by columnar epithelial cells with prominent apical cytoplasmic snouts, intraluminal secretions, and varying degrees of nuclear atypia and architectural complexity. The appearance of some of these lesions is worrisome, but diagnostic difficulties arise because the histologic features do not fulfill established criteria for the diagnosis of atypical ductal hyperplasia or ductal carcinoma in situ (DCIS). We have termed such lesions columnar alteration with prominent apical snouts and secretions (CAPSS). The purpose of this study was to define the pathologic spectrum and mammographic features of these lesions. We reviewed histologic sections and mammograms from 100 consecutive breast biopsies performed for microcalcifications. The prevalence and histologic features of CAPSS and the association with other histologic findings were recorded. CAPSS was identified in 42% of cases. At the lower end of the spectrum were lesions similar to columnar alteration of lobules but in which apical cytoplasmic secretion and nuclear stratification were more pronounced and cells with a hobnail configuration were common. More advanced lesions showed columnar epithelial cell tufts, bridges, and micropapillations with prominent apical cytoplasmic snouts and with greater degrees of nuclear stratification and atypia. At the upper end of the spectrum were lesions that could arguably be considered DCIS. Calcifications were present within CAPSS in 74% of cases, were frequently psammomatous, and were typically nonbranching and often round on mammography. Columnar alteration of lobules was more common in biopsies with than without CAPSS (74 versus 36%, p < 0.001). Ductal carcinoma in situ was seen with similar frequency in biopsies with and without CAPSS (38 versus 41%). However, DCIS in cases with CAPSS was more often of the low-grade micropapillary-cribriform type than in cases without CAPSS (56 versus 17%, p < 0.01), and CAPSS and DCIS commonly coexisted in the same or adjacent TDLUs. In conclusion, 1) CAPSS encompasses a spectrum of lesions bounded at the lower end by columnar alteration of lobules and at the upper end by low-grade DCIS. Lesions recently described by Page as "hypersecretory hyperplasia with atypia" fall within this spectrum. 2) Some CAPSS lesions present architectural or cytologic features that create diagnostic difficulties and raise the possibility of atypical ductal hyperplasia or DCIS; however, the level of cancer risk associated with CAPSS lesions that do not fulfill established criteria for atypical ductal hyperplasia or DCIS is unknown and requires evaluation in follow-up studies.

Reovirus growth in cell culture does not require the full complement of viral proteins: identification of a sigma1s-null mutant

The reovirus sigma1s protein is a 14-kDa nonstructural protein encoded by the S1 gene segment. The S1 gene has been linked to many properties of reovirus, including virulence and induction of apoptosis. Although the function of sigma1s is not known, the sigma1s open reading frame is conserved in all S1 gene sequences determined to date. In this study, we identified and characterized a variant of type 3 reovirus, T3C84-MA, which does not express sigma1s. To facilitate these experiments, we generated two monoclonal antibodies (MAbs) that bind different epitopes of the sigma1s protein. Using these MAbs in immunoblot and immunofluorescence assays, we found that L929 (L) cells infected with T3C84-MA do not contain sigma1s. To determine whether sigma1s is required for reovirus infection of cultured cells, we compared the growth of T3C84-MA and its parental strain, T3C84, in L cells and Madin-Darby canine kidney (MDCK) cells. After 48 h of growth, yields of T3C84-MA were equivalent to yields of T3C84 in L cells and were fivefold lower than yields of T3C84 in MDCK cells. After 7 days of growth following adsorption at a low multiplicity of infection, yields of T3C84-MA and T3C84 did not differ significantly in either L cells or MDCK cells. To determine whether sigma1s is required for apoptosis induced by reovirus infection, T3C84-MA and T3C84 were tested for their capacity to induce apoptosis, using an acridine orange staining assay. In these experiments, the percentages of apoptotic cells following infection with T3C84-MA and T3C84 were equivalent. These findings indicate that nonstructural protein sigma1s is not required for reovirus growth in cell culture and does not influence the capacity of reovirus to induce apoptosis. Therefore, reovirus replication does not require the full complement of virally encoded proteins.

Predictors of breast recurrence after conservative surgery and radiation therapy for invasive breast cancer

The majority of women with breast cancer are adequately treated with breast-conserving surgery and radiation therapy. Although most women need very limited surgery, some require a larger volume of resection to attain a high level of local control, and some might even require a mastectomy. This article summarizes the current state of knowledge concerning the assessment of the adequacy of excision.

Skin recurrences after breast-conserving therapy for early-stage breast cancer

PURPOSE

To assess the frequency and prognosis of skin recurrences after breast-conserving therapy (BCT) compared with other breast recurrences.

MATERIALS AND METHODS

From 1968 to 1986, 1,624 patients with unilateral stage I or II breast cancer treated with BCT at the Joint Center for Radiation Therapy (Boston, MA) underwent gross tumor excision and received a dose of > or = 60 Gy to the tumor bed. Skin recurrences (SR) were defined as breast recurrences without associated parenchymal disease. An invasive breast recurrence with any parenchymal disease noted clinically or radiographically was scored as an other breast recurrence (OBR). Median follow-up for survivors was 137 months.

RESULTS

SR represented 8% (18 of 229) of all breast recurrences and occurred in 1.1% of all patients. The outcome after local recurrence was different for patients with SR and invasive OBR. Patients with SR more frequently had uncontrolled local failure (50%; 9 of 18) than did patients with OBR (14%; 26 of 188) (P = .0007). Forty-four percent (8 of 18) of patients with SR had distant metastasis simultaneously or within 2 months of the recurrence compared with 5% (9 of 188) of invasive OBR patients (P < .0001). For patients without distant metastasis at the time of recurrence, the 5-year actuarial rate of development of distant metastasis was 60% for SR patients compared with 39% for invasive OBR patients (P = .07), and the corresponding 5-year actuarial survival rates beyond the time of local failure were 51% and 79%, respectively (P = .06).

CONCLUSION

In contrast to other types of invasive breast recurrence after breast-conserving therapy, skin recurrences are rare and are associated with a significantly higher rate of distant metastasis and uncontrolled local disease as well as a lower rate of survival.

Risk of breast cancer associated with atypical hyperplasia of lobular and ductal types

Epidemiological studies using the histological classification of Page for benign breast disease consistently demonstrate a positive association between atypical hyperplasia and the subsequent development of breast cancer. However, atypical hyperplasia is of either lobular or ductal types, and breast cancer risk in relation to type of atypical hyperplasia has not been studied extensively. Thus, we investigated prospectively the risk of breast cancer associated with histological subtypes of benign proliferative breast disease, including the types of atypical hyperplasia, among participants in the Nurses' Health Study who had biopsy-confirmed benign breast disease. Women who subsequently developed breast cancer were matched by year of birth and year of biopsy to participants who were free from breast cancer. Benign biopsy slides were classified according to the criteria of Page. Odds ratios (ORs) of breast cancer and 95% confidence intervals (CIs), adjusted for the matching variables and other breast cancer risk factors, were computed using unconditional logistic regression with benign nonproliferative breast disease as the referent group. Atypical ductal hyperplasia (OR = 2.4; 95% CI, 1.3-4.5) or atypical lobular hyperplasia (OR = 5.3; 95% CI, 2.7-10.4) in a prior biopsy were associated with increased breast cancer risk. Atypical lobular hyperplasia was more strongly associated with the risk of premenopausal breast cancer (OR = 9.6; 95% CI, 3.3-27.8) than with the risk of postmenopausal breast cancer (OR = 3.7; 95% CI, 1.3-10.2). The association of atypical ductal hyperplasia and breast cancer risk varied little by menopausal status. The magnitude of breast cancer risk seems to vary according to the type of atypical hyperplasia present at biopsy.

The relationship between shaved margin and inked margin status in breast excision specimens

BACKGROUND

The presence of tumor at the inked margins (IMs) of breast specimens is associated with an increased risk of local recurrence after breast-conserving therapy for invasive breast carcinoma and ductal carcinoma in situ (DCIS). Given the importance of margin status, some have advocated the use of shaved margins (SMs) as a means of conducting a more complete examination of the specimen margins than could be done with sections taken perpendicular to the IMs. However, it is not known whether these two methods of margin assessment provide comparable information.

METHODS

To address this issue, the authors studied 22 consecutive breast reexcision specimens (10 DCIS, 6 infiltrating ductal carcinomas, and 6 infiltrating lobular carcinomas) in which the specimen surfaces were inked, the margins were shaved, and tumor was present in at least one of the SM sections. A total of 199 SMs were examined. The SMs were originally embedded in a way that permitted histologic sections to be cut opposite the inked surface. Sections of SM stained with hematoxylin and eosin (H & E) were reviewed and scored for the presence and extent (number of low-power fields) of cancer. The remaining tissue from the SM was then removed from the blocks, cut perpendicular to the IM, and reembedded to permit visualization of tumor in relation to the IM. Sections were then cut from two different levels of each reembedded block and stained with H & E. An SM was considered positive if tumor was present anywhere on the section. An IM was considered positive when tumor extended to the inked surface.

RESULTS

Although all 22 excisions had at least 1 positive SM, tumor was present at an IM in only 12 specimens (55%). Among 69 positive SMs, the corresponding IM was positive in only 42 (61%). The likelihood of a positive IM increased with the number of low-power fields of involvement by invasive carcinoma or DCIS on the SM, as follows: 19% with 1 low power-field, 67% with 2 low-power fields, and 97% with > or = 3 low-power fields (all P < 0.02). When the SM was negative, the corresponding IM was negative in 98% of cases.

CONCLUSIONS

Many patients with positive SMs do not have positive IMs. A positive SM more reliably predicts a positive IM when tumor involves > or = 3 low-power fields of the SM. The authors conclude that the clinical implications of a positive SM may not be the same as those of a positive IM. Clinical outcome studies are needed to define further the implications of positive SMs. [See editorial counterpoint on pages 1453-8 and reply to counterpoint on pages 1459-60, this issue.]

Breast-conserving therapy for stage I-II synchronous bilateral breast carcinoma

BACKGROUND

Synchronous bilateral breast carcinoma (SBBC) is an uncommon presentation, and the management of patients with this disease is not well established.

METHODS

In order to evaluate whether patients with early-stage SBBC could be safely and effectively treated with bilateral breast-conserving therapy (BCT), the authors retrospectively reviewed the records of 24 patients with clinical Stage I-II SBBC treated during the period 1977-1989 with bilateral BCT. SBBC was defined as bilateral invasive carcinomas diagnosed no more than 1 month apart. The median age at diagnosis was 56 years (range, 32-85 years), and the median follow-up for surviving patients was 95 months (range, 68-157 months). Pathology slides were available for review in 19 cases. Cosmetic results and complications after BCT were scored. Outcome was compared with that of 1314 patients with unilateral Stage I or II breast carcinoma, within the same age range, treated during the same time period.

RESULTS

There were no significant differences between the SBBC and unilateral groups in actuarial disease free survival (70% and 74%, respectively, at 5 years), overall survival (88% and 87%, respectively, at 5 years), or crude distribution of sites of first failure. Multivariate analysis of overall survival and disease free survival also did not show bilaterality to be a significant factor. The cosmetic results for the SBBC group were not significantly different from those for the unilateral group. Physician assessment of cosmetic outcome was excellent in 57% and good in 43% of SBBC patients evaluated 25-48 months after BCT. Long term complications were rare in both groups.

CONCLUSIONS

Patients with early-stage SBBC can be safely treated with carefully planned, bilateral BCT, with outcome that appears to be comparable to that of patients with early-stage unilateral breast carcinoma.

Pathologic margin involvement and the risk of recurrence in patients treated with breast-conserving therapy

BACKGROUND

The relationship between the microscopic margins of resection and ipsilateral breast recurrence (IBR) after breast-conserving therapy for carcinomas with or without an extensive intraductal component (EIC) has not been adequately defined.

METHODS

Of 1,790 women with unilateral clinical Stage I or II breast carcinoma treated with radiation therapy as part of breast-conserving therapy, 343 had invasive ductal histology evaluable for an extensive intraductal component (EIC), had inked margins that were evaluable for an review of their pathology slides, and received > or = 60 Gray to the tumor bed; these 343 women constitute the study population. The median follow-up was 109 months. All available slides were reviewed by one of the study pathologists. Final inked margins of excision were classified as negative > 1 mm (no invasive or in situ ductal carcinoma within 1 mm of the inked margin); negative-1 mm, or close carcinoma < or = 1 mm from the inked margin but not at the margin); or positive (carcinoma at the inked margin). A focally positive margin was defined as invasive or in situ ductal carcinoma at the margin in three or fewer low-power fields. The first site of recurrent disease was classified as either ipsilateral breast recurrence (IBR) or distant metastasis/regional lymph node failure.

RESULTS

Crude rates for the first site of recurrence were calculated first for all 340 patients evaluable at 5 years, then separately for the 272 patients with EIC-negative cancers and the 68 patients with EIC-positive cancers. The 5-year rate of IBR for all patients with negative margins was 2%; and for all patients with positive margins, the rate was 16%. Among patients with negative margins, the 5-year rate of IBR was 2% for all patients with close margins (negative < or = 1 mm) and 3% for those with negative > 1 mm margins. For patients with close margins, the rates were 2% and 0% for EIC-negative and EIC-positive tumors, respectively; the corresponding rates for patients with negative margins > 1 mm were 1% and 14%. The 5-year rate of IBR for patients with focally positive margins was 9% (9% for EIC-negative and 7% for EIC-positive patients). The 5-year crude rate of IBR for patients with greater than focally positive margins was 28% (19% for EIC-negative and 42% for EIC-positive patients).

CONCLUSIONS

Patients with negative margins of excision have a low rate of recurrence in the treated breast, whether the margin is > 1 mm or < or = 1 mm and whether the carcinoma is EIC-negative or EIC-positive. Among patients with positive margins, those with focally positive margins have a considerably lower risk of local recurrence than those with more than focally positive margins, and could be considered for breast-conserving therapy.

Widespread loss of gelsolin in breast cancers of humans, mice, and rats

Down-regulation of gelsolin, an actin-binding protein, is frequently found in several types of transformed cells and tumors. The present study demonstrates that gelsolin protein and RNA were absent or markedly reduced in human breast cancer cell lines relative to "normal" mortal human mammary epithelial cells and benign, immortalized cell lines. Moreover, actin filaments were usually attenuated coincident with the reduction in gelsolin. Gelsolin was also missing or greatly decreased in 70% of 30 human sporadic, invasive breast carcinomas examined by immunocytochemistry and in 100% of virally induced mouse and chemically induced rat mammary carcinomas evaluated by Northern analysis. Southern analysis revealed no major mutations in the gelsolin gene of human breast cancer cells. Our results show that partial or total loss of gelsolin expression is common to the majority of breast cancers of diverse etiologies in three animal species and point to gelsolin as a candidate suppressor of breast cancer.

Relationship of tumor grade to other pathologic features and to treatment outcome of patients with early stage breast carcinoma treated with breast-conserving therapy

BACKGROUND

Although histologic grade has previously been described as a predictor of distant failure, it is uncertain whether histologic grade should be used to decide which patients should undergo axillary lymph node dissection and whether grade should be considered as a selection factor for breast-conserving therapy.

METHODS

The authors retrospectively analyzed data from 1081 patients with American Joint Committee on Cancer Stage I or II infiltrating ductal carcinoma treated with breast-conserving therapy at the Joint Center for Radiation Therapy between 1970 and 1986. All patients had pathology slides reviewed by one of two study pathologists. Using the Elston modification of the Bloom-Richardson grading system, patients were divided by histologic grade into 3 groups (219 with Grade I, 482 with Grade II, and 380 with Grade III). The median follow-up time for 716 survivors was 134 months. The incidence of various pathologic features was examined with respect to histologic grade. In addition, the 10-year crude rates of failure (by first site) were examined as they related to grade. A polychotomous logistic regression model was used to determine the effect of grade on local and distant failure.

RESULTS

High grade tumors tended to be larger, to exhibit more mononuclear cellular reaction and necrosis, and were more likely to be estrogen receptor negative. Patients with high grade tumors were also younger than those with lower grade tumors. The incidence of an extensive intraductal component and lymphatic vessel invasion did not vary significantly by histologic grade. The incidence of pathologic lymph node metastases also did not vary by grade, even when stratified by tumor size. In both univariable and multivariable analyses, the 10-year crude rate of local recurrence was not related to histologic grade (P = 0.44). Distant recurrence rates, however, were significantly higher as grade increased (p = 0.002).

CONCLUSIONS

Higher histologic grade predicted an increased incidence of distant recurrence, but not a greater likelihood of axillary lymph node metastases or local recurrence after breast-conserving therapy. The authors conclude that grade should not be used to make decisions regarding local management.

A prospective study of conservative surgery alone in the treatment of selected patients with stage I breast cancer

BACKGROUND

Randomized clinical trials have clearly demonstrated that the use of radiation therapy (RT) following breast-conserving surgery (CS) substantially reduces the risk of local recurrence. However, the low rate of local recurrence after CS and RT for patients without known risk factors, and the recent increase in the detection of smaller cancers due to mammographic screening have led to the speculation that a subgroup of patients who have a low risk of local recurrence without RT might be identified. In 1986, we initiated a one-arm, prospective clinical trial of CS alone for treatment of highly selected breast cancer patients without known risk factors for local recurrence.

METHODS

The study had a sequential design with a planned accrual of 90 patients. Criteria for entry into the trial were: a unicentric, clinical TI infiltrating ductal, mucinous or tubular carcinoma without an extensive intraductal component or lymphatic vessel invasion; a wide excision with a pathologically-documented negative margin of at least 1 cm; and histologically negative axillary lymph nodes. No adjuvant RT or systemic therapy was administered. Seventy-six per cent of the lesions were detected by mammography alone. The median gross pathologic tumor size was 0.9 cm. The median patient age was 67 years.

RESULTS

Eighty-seven patients were enrolled in the trial before it closed prematurely in 1992 because the predefined stopping boundary was crossed (i.e., the sixth local recurrence was observed). At that time, the average annual local recurrence rate was 4.2%. With a median follow-up of 56 months, there are now 14 patients (16%) with local recurrence as their site of first failure (average annual local recurrence rate: 3.6%). Four patients without local recurrence developed distant metastases. Three patients have died, one of metastatic breast cancer and two of unrelated causes.

CONCLUSIONS

Even in a highly selected group of patients with early-stage breast cancer, there is a substantial risk of early local recurrence for those treated with wide excision alone.

Local recurrence after conservative surgery and radiation therapy for ductal carcinoma in situ: Possible importance of family history

PURPOSE

The optimal treatment of ductal carcinoma in situ is controversial. Traditionally, women with this disease have been treated with mastectomy with excellent results, but recently the need for such extensive surgery has been questioned. Long-term data on the use of conservative surgery and radiation therapy for treatment are limited. A retrospective analysis was performed to assess treatment outcome and prognostic factors for patients with ductal carcinoma in situ treated with conservative surgery and radiotherapy.

PATIENTS AND METHODS

From 1976 to 1990, 76 women with ductal carcinoma in situ were treated with conservative surgery followed by radiation therapy. The median age at diagnosis was 48 years. Seventeen patients had a positive family history of breast cancer in a first-degree (n=8) or second-degree (n=9) relative. Median follow-up interval was 74 months for the 71 survivors. In 54 patients, the carcinoma was detected by mammography alone; in 13 patients, by mammography and physical examination; and in 4 patients, by physical examination with a normal mammogram; and in 5 patients, by physical examination alone without mammography. Fifty patients had re-excision after initial biopsy. Final margins were positive in 11, close in 11, negative in 34, and unknown in 20. The median volume of excised tissue was 60 cm3. The axilla was surgically staged in 30 patients (39%) and all were negative. The whole breast was irradiated to a dose of 45 to 50 Gy in all patients. Seventy-two patients also received a boost to the primary site. The median total radiation dose to the primary site was 61 Gy (range, 46 to 71).

RESULTS

Seven patients had a recurrence in the treated breast at 16, 18, 41, 63, 72, 83, and 104 months after treatment. The 5- and 10-year actuarial rates of local recurrence were 4% and 15%, respectively. Six of seven recurrences occurred in the vicinity of the original lesion. Four local recurrences were invasive, and three were ductal carcinoma in situ. Two patients developed a contralateral invasive carcinoma. The 5- and 10-year cause-specific survival rates were 100% and 96%, respectively. The 10-year actuarial rate of local recurrence was 25% in the group with a total excision volume less than 60 cm3, as compared with 0% in those with 60 cm3 or more excised (P=0.04). In patients with a positive family history, the 10-year actuarial rate of local recurrence was 37%, as compared with 9% in patients with a negative family history (P=0.008). Of the 17 patients with a positive family history, four developed either an ipsilateral or contralateral invasive breast cancer, whereas 1 of the 58 patients without a family history developed a subsequent invasive breast cancer (P=0.008).

CONCLUSION

These results suggest that patients with ductal carcinoma in situ treated with conservative surgery and radiotherapy (including a boost to the primary site) appear to benefit from wide, rather than limited, resection. These results also suggest that family history may be an important prognostic factor for progression of disease.

Expression of vascular permeability factor (vascular endothelial growth factor) and its receptors in breast cancer

Solid tumors must induce a vascular stroma to grow beyond a minimal size, and the intensity of the angiogenic response has been correlated with prognosis in breast cancer patients. Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), is a secreted protein that has been implicated in tumor-associated angiogenesis. Vascular permeability factor directly stimulates endothelial cell growth and also increases microvascular permeability, leading to the extravasation of plasma proteins, which alter the extracellular matrix in a manner that promotes angiogenesis. To determine whether VPF has a role in breast cancer, we used in situ hybridization to study VPF mRNA expression in normal breast tissue (13 specimens), comedo-type ductal carcinoma in situ (DCIS) (four specimens), infiltrating ductal carcinoma (12 specimens), infiltrating lobular carcinoma (two specimens), metastatic ductal carcinoma (three specimens) and metastatic lobular carcinoma (one specimen). Vascular permeability factor mRNA was expressed at a low level by normal duct epithelium but was expressed at high levels in tumor cells in all cases of comedo-type DCIS, infiltrating ductal carcinoma, and metastatic ductal carcinoma. In contrast, VPF mRNA was not expressed at high levels in infiltrating lobular carcinoma. We also used in situ hybridization to study the expression of two recently described endothelial cell surface VPF receptors, flt-1 and kdr. Vascular permeability factor receptor mRNA was strongly expressed in endothelial cells of small vessels adjacent to malignant tumor cells in DCIS, infiltrating ductal carcinoma, and metastatic ductal carcinoma. In contrast, no definite labeling for receptor mRNA was detected in infiltrating lobular carcinoma or nonmalignant breast tissue. The intense expression of VPF mRNA by breast carcinoma cells and of VPF receptor mRNA by endothelial cells of adjacent small blood vessels provides strong evidence linking VPF expression to the angiogenesis associated with comedo-type DCIS, infiltrating ductal, and metastatic ductal breast carcinoma.

The relationship between microscopic margins of resection and the risk of local recurrence in patients with breast cancer treated with breast-conserving surgery and radiation therapy

BACKGROUND

The relationships among the involvement of tumor at the final margins of resection, the presence of an extensive intraductal component (EIC), and the risk of local recurrence are important considerations in patients treated with conservative surgery and radiation therapy for early stage breast cancer but have not been defined adequately.

METHODS

Between 1982 and 1985, 885 patients were treated for clinical Stage I or II invasive breast cancer. The study population was limited to 181 patients with an infiltrating ductal carcinoma who received a radiation dose to the surgical site of 60 Gy or greater, whose final microscopic margins of resection were evaluable, and who had at least 5 years of follow-up. A positive margin was defined as tumor present at the inked margin of resection, a close margin as tumor within 1 mm of the inked margin, and a negative margin as no tumor within 1 mm of the inked margin. A focally positive margin was defined as tumor at the margin in three or fewer low-power fields. In 157 patients (87%), the tumor was evaluable for the presence or absence of an EIC. The median follow-up was 86 months.

RESULTS

In 12 of 181 patients (7%), a recurrence developed at or near the primary site (true recurrence/marginal miss [TR/MM]) within 5 years. The 5-year rate of TR/MM (with 95% confidence intervals) among patients with negative, close, focally positive, and more than focally positive margins was 0% (0-4%), 4% (0-20%), 6% (1-17%) and 21% (10-37%), respectively. Patients with positive margins also were more likely to have a distant failure within 5 years (14%, 8%, 25%, and 32% in the four groups, respectively). However, patients with positive margins more often had positive axillary lymph nodes than patients with negative or close margins (59% vs. 38%, P < 0.02). The 5-year rate of TR/MM was 20% for patients with an EIC-positive tumor and 7% for patients with an EIC-negative tumor. However, among the 127 patients with an EIC-negative tumor, the 5-year rate of TR/MM was less than 10% in all margin groups. Among the 30 patients with an EIC-positive tumor, the 5-year rate of TR/MM was 0% when margins were negative or close but 50% when margins were more than focally positive.

CONCLUSIONS

These results provide support for the use of breast-conserving surgery and breast irradiation in all patients with uninvolved margins, whether the tumor is EIC-positive or EIC-negative. This study suggests that breast-conserving therapy (including a radiation boost to the primary site) also may be a reasonable option for some patients with an EIC-negative tumor and margin involvement.

The relation between the surgery-radiotherapy interval and treatment outcome in patients treated with breast-conserving surgery and radiation therapy without systemic therapy

PURPOSE

This analysis was performed to clarify the relationship between the surgery-radiotherapy interval and the risk of recurrence in patients treated with breast-conserving therapy for early stage invasive cancers.

METHODS AND MATERIALS

We retrospectively analyzed data from 653 patients with American Joint Commission on Cancer Stage I or II, pathologically node-negative breast cancer treated by breast-conserving therapy without adjuvant systemic therapy between 1968 and 1985. All patients received a dose of at least 60 Gy to the tumor bed. Two hundred and eighty-three patients started radiotherapy within 4 weeks of surgery, 308 started 5-8 weeks after surgery, and 54 started 9-12 weeks after surgery. Median follow-up in the 531 survivors was 100 months.

RESULTS

Pathologic features and treatment characteristics were well balanced between the groups with surgery-radiotherapy intervals of 0-4 weeks and 5-8 weeks. There was no statistically difference in the risk of overall recurrence among patients starting radiotherapy 5-8 weeks after surgery compared with those treated within 4 weeks. Analysis of the 5-year crude rates of failure further demonstrated no difference in the distribution of sites of failure in the 5-8 week group compared with the 0-4 week group. A multivariate model controlling for known risk factors, as well as potential treatment-related confounders, also failed to demonstrate an increased risk of recurrence with the longer surgery-radiotherapy interval (risk ratio = 0.89, p = 0.44).

CONCLUSION

This retrospective analysis suggests that a delay of up to 8 weeks in the interval between the last breast surgery and the start of radiotherapy is not associated with an increased risk of recurrence in patients with early stage breast cancer treated with breast irradiation to at least 60 Gy without systemic therapy.

Relationship of patient age to pathologic features of the tumor and prognosis for patients with stage I or II breast cancer

PURPOSE

This analysis was performed to clarify the relationship of young age at diagnosis to the pathologic features of the tumor and prognosis in patients with early-stage breast cancer.

PATIENTS AND METHODS

We retrospectively analyzed data from 1,398 patients with American Joint Committee on Cancer Staging stage I or II breast cancer treated by breast-conserving therapy between 1968 and 1985. One hundred seven patients were younger than 35 years at the time of diagnosis. The median follow-up duration for the 1,032 survivors was 99 months.

RESULTS

Patients younger than 35 years had a significantly higher overall recurrence rate (P = .002), as well as a greater risk for developing distant metastases (P = .03), when compared with older patients. The cancers in younger patients more commonly showed factors associated with a worse prognosis (including grade 3 histology, lymphatic vessel invasion [LVI], necrosis, and estrogen receptor [ER] negativity) as compared with older patients. In a proportional hazards model that included clinical and treatment-related variables, as well as these pathologic features, age younger than 35 years remained a significant predictor for time to recurrence (relative risk [RR], 1.70), time to distant failure (RR, 1.60), and overall mortality (RR, 1.50).

CONCLUSION

Breast cancer patients younger than 35 years have a worse prognosis than older patients. This difference is only partially explained by a higher frequency of adverse pathologic factors seen in younger patients.

Contralateral breast cancer: clinical characteristics and impact on prognosis

PURPOSE

To determine the characteristics of patients with unilateral breast cancer who subsequently develop contralateral breast cancer (CBC), to assess their prognosis relative to patients who do not develop a CBC, and to assess the feasibility of using conservative surgery (CS) and radiotherapy (RT) to treat CBC.

MATERIALS AND METHODS

Of 1,624 women treated with CS and RT for unilateral stage I or II breast cancer at the Joint Center for Radiation Therapy, 77 developed an invasive CBC. Sixty-two CBCs were treated with CS and RT. The median follow-up duration was 95 months from the time of initial breast cancer diagnosis, and 63 months from CBC diagnosis.

RESULTS

The cumulative actuarial rate of CBC was 7.0% at 10 years, and the annual incidence rate for CBC was relatively constant. Young age predicted for CBC. When age was analyzed by decade the relative risk (RR) for older patients compared with younger patients was 0.79 (95% confidence interval [CI], 0.62 to 1.01). The presence of lobular carcinoma in situ (LCIS), higher tumor stage, and lack of adjuvant systemic therapy also predicted for CBC with borderline significance. Multivariate analyses showed that CBC was associated with a statistically significant greater likelihood of local recurrence (LR) or distant recurrence (RR, 1.68; 95% CI, 1.03 to 2.71), and distant-only recurrence (RR, 2.17; 95% CI, 1.28 to 3.69). Among assessable patients treated with bilateral RT, 28 of 31 ipsilateral and 11 of 11 contralateral breasts had an excellent or good overall cosmetic outcome at 5 years, and treatment-related complications were minimal.

CONCLUSION

We conclude that (1) young age is associated with a greater likelihood of CBC, (2) patients who develop a CBC have a greater subsequent risk of distant relapse as compared with patients without CBC, and (3) it is feasible to deliver sequential nonoverlapping bilateral RT without compromising the cosmetic outcome or increasing complications.

Clinical and histologic aspects of proliferative and non-proliferative benign breast disease

It has been known for years that benign breast disease is correlated with an increased risk for the development of breast cancer. Over the years, there have been many studies linking histological changes in benign breast biopsies and subsequent risk of breast cancer. In many of these reports, there was no attempt to standardize criteria and often the patient population under study was relatively small. Over the past decade, three large groups have agreed to use the same definition of benign changes and a unified set of criteria for the diagnosis of these lesions. The results from these three groups [Nashville, Nurses Health Study (NHS), and the Breast Cancer Detection Demonstration Project (BCDDP)] are strikingly similar. All three studies reported that if the biopsy revealed proliferative disease without atypia, the subsequent risk was approximately 1.5x. If the biopsy revealed atypical hyperplasia (AH), the risk was approximately 4.5x. If the patients with AH had a family history of breast cancer, their subsequent risk approached that of patients with in situ carcinoma (approximately 8-10x). In addition to family history, menopausal status seemed to play a role. In patients with AH, the breast cancer risk was much higher in pre- than post-menopausal patients. While the classification scheme proposed by Page and co-workers is useful in assigning different levels of risk to women with benign breast disease, it has not been universally accepted. Our major short-term goal should be to encourage pathologists to apply these criteria in a reproducible manner in their daily practice.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognosis following salvage mastectomy for recurrence in the breast after conservative surgery and radiation therapy for early-stage breast cancer

PURPOSE

The prognosis and factors that influence prognosis following salvage mastectomy in patients with recurrence in the treated breast after conservative surgery (CS) and radiation therapy (RT) were investigated.

MATERIALS AND METHODS

A total of 1,593 patients with stage I or II invasive breast cancer were treated following gross total excision of the tumor at the Joint Center for Radiation Therapy (JCRT) between 1968 and 1985. One hundred sixty-six of the 1,593 (10%) had subsequent recurrence in the breast. Of these, 123 had salvage mastectomy and constitute the study population. The recurrent tumor was predominantly invasive in 99 patients, noninvasive in 14, and focally invasive in 10. Following mastectomy, chemotherapy or hormonal therapy was administered to 29 patients. The median follow-up time was 39 months after salvage mastectomy.

RESULTS

The 5-year actuarial rate of further local or distant relapse for the entire group was 41%. None of the 24 patients with focally invasive or noninvasive tumors had a subsequent relapse. In comparison, the 5-year actuarial rate of further relapse in the 99 patients with a predominantly invasive recurrence was 52% (P = .001). The method of detection of the recurrence, the age of the patient at initial diagnosis, the disease-free interval, and the location of the recurrence in the breast were not found to have a statistically significant association with the risk of further relapse.

CONCLUSION

We conclude that the histology of the recurrent tumor is an important prognostic factor for the risk of further relapse. Patients with purely noninvasive or focally invasive tumors have an excellent prognosis following salvage mastectomy. In contrast, patients with predominantly invasive tumors are at substantial risk for further relapse.

Interobserver reproducibility in the diagnosis of ductal proliferative breast lesions using standardized criteria

Although the categorization of proliferative breast lesions provides valuable information regarding subsequent risk of breast cancer, the ability of pathologists to classify such lesions in a reproducible fashion has not been adequately evaluated. To assess further interobserver reproducibility in the categorization of proliferative breast lesions, six pathologists each reviewed 24 proliferative ductal lesions and classified them as either usual hyperplasia (H), atypical hyperplasia (AH), or carcinoma in situ (CIS). Before evaluation of the study slides, all the participants were instructed to use the diagnostic criteria of Page and co-workers and were provided with both a written summary of these criteria and a set of teaching slides with representative examples of each type of lesion. Complete agreement among all six pathologists was seen in 14 cases (58%); five or more agreed in 17 cases (71%); and four or more arrived at the same diagnosis in 22 cases (92%). No pathologist consistently rendered more "benign" or "malignant" diagnoses than any other. After assigning numerical values for each diagnostic category (H = 1, AH = 2, CIS = 3), the scores for the group of 24 cases did not differ significantly by pathologist (p = 0.68; average score range, 1.7-2.0). Our results indicate that with the use of standardized criteria, interobserver concordance in the diagnosis of proliferative ductal breast lesions can be obtained in the majority of cases.