Long-lasting memory of jasmonic acid-dependent immunity requires DNA demethylation and ARGONAUTE1.

Stress can have long-lasting impacts on plants. Here we report the long-term effects of the stress hormone jasmonic acid (JA) on the defence phenotype, transcriptome and DNA methylome of Arabidopsis. Three weeks after transient JA signalling, 5-week-old plants retained induced resistance (IR) against herbivory but showed increased susceptibility to pathogens. Transcriptome analysis revealed long-term priming and/or upregulation of JA-dependent defence genes but repression of ethylene- and salicylic acid-dependent genes. Long-term JA-IR was associated with shifts in glucosinolate composition and required MYC2/3/4 transcription factors, RNA-directed DNA methylation, the DNA demethylase ROS1 and the small RNA (sRNA)-binding protein AGO1. Although methylome analysis did not reveal consistent changes in DNA methylation near MYC2/3/4-controlled genes, JA-treated plants were specifically enriched with hypomethylated ATREP2 transposable elements (TEs). Epigenomic characterization of mutants and transgenic lines revealed that ATREP2 TEs are regulated by RdDM and ROS1 and produce 21 nt sRNAs that bind to nuclear AGO1. Since ATREP2 TEs are enriched with sequences from IR-related defence genes, our results suggest that AGO1-associated sRNAs from hypomethylated ATREP2 TEs trans-regulate long-lasting memory of JA-dependent immunity.

Prediction and monitoring of relapse in stage III melanoma using circulating tumor DNA.

BACKGROUND: The advent of effective adjuvant therapies for patients with resected melanoma has highlighted the need to stratify patients based on risk of relapse given the cost and toxicities associated with treatment. Here we assessed circulating tumor DNA (ctDNA) to predict and monitor relapse in resected stage III melanoma. PATIENTS AND METHODS: Somatic mutations were identified in 99/133 (74%) patients through tumor tissue sequencing. Personalized droplet digital PCR (ddPCR) assays were used to detect known mutations in 315 prospectively collected plasma samples from mutation-positive patients. External validation was performed in a prospective independent cohort (n = 29). RESULTS: ctDNA was detected in 37 of 99 (37%) individuals. In 81 patients who did not receive adjuvant therapy, 90% of patients with ctDNA detected at baseline and 100% of patients with ctDNA detected at the postoperative timepoint relapsed at a median follow up of 20 months. ctDNA detection predicted patients at high risk of relapse at baseline [relapse-free survival (RFS) hazard ratio (HR) 2.9; 95% confidence interval (CI) 1.5-5.6; P = 0.002] and postoperatively (HR 10; 95% CI 4.3-24; P < 0.001). ctDNA detection at baseline [HR 2.9; 95% CI 1.3-5.7; P = 0.003 and postoperatively (HR 11; 95% CI 4.3-27; P < 0.001] was also associated with inferior distant metastasis-free survival (DMFS). These findings were validated in the independent cohort. ctDNA detection remained an independent predictor of RFS and DMFS in multivariate analyses after adjustment for disease stage and BRAF mutation status. CONCLUSION: Baseline and postoperative ctDNA detection in two independent prospective cohorts identified stage III melanoma patients at highest risk of relapse and has potential to inform adjuvant therapy decisions.

Multiplex immunohistochemistry accurately defines the immune context of metastatic melanoma.

A prospective study explored the heterogeneous nature of metastatic melanoma using Multiplex immunohistochemistry (IHC) and flow cytometry (FACS). Multiplex IHC data quantitated immune subset number present intra-tumoral (IT) vs the tumor stroma, plus distance of immune subsets from the tumor margin (TM). In addition, mIHC showed a close association between the presence of IT CD8+ T cells and PDL1 expression in melanoma, which was more prevalent on macrophages than on melanoma cells. In contrast, FACS provided more detailed information regarding the T cell subset differentiation, their activation status and expression of immune checkpoint molecules. Interestingly, mIHC detected significantly higher Treg numbers than FACS and showed preferential CD4+ T cell distribution in the tumor stroma. Based on the mIHC and FACS data, we provide a model which defines metastatic melanoma immune context into four categories using the presence or absence of PDL1+ melanoma cells and/or macrophages, and their location within the tumor or on the periphery, combined with the presence or absence of IT CD8+ T cells. This model interprets melanoma immune context as a spectrum of tumor escape from immune control, and provides a snapshot upon which interpretation of checkpoint blockade inhibitor (CBI) therapy responses can be built.

Subungual melanoma: Management in the modern era.

Subungual melanoma is a rare subtype of cutaneous melanoma that arises from the structures of the nail apparatus. It presents most commonly in older patients and at an advanced stage. A retrospective review of all patients with subungual melanoma in a single institution over a 15-year period was performed. In total, 54 patients were included (26 males, average age 62.9 years), of which 28 cases involved the upper limb. Median tumour thickness was 4.5 mm. Eighteen patients had lymph node metastasis at diagnosis, including 11 of 36 patients with positive sentinel lymph node biopsy. Median survival was 4.6 years. Subungual melanoma has a poor prognosis that is strongly associated with presence of nodal disease at diagnosis. Sentinel lymph node biopsy should be considered to determine stage and prognosis.

Localized melanoma in older patients, the impact of increasing age and comorbid medical conditions.

BACKGROUND: Elderly patients experience a different spectrum of disease and poorer outcomes than younger patients. This study investigated the impact of age and medical comorbidities on the management and outcome of patients ≥65 years. METHODS: A retrospective review of all patients ≥65 years (481 patients with 525 primary melanomas) presenting with AJCC clinical stage I-II melanoma to an Australian cancer centre between 2000 and 2008. RESULT: The median age was 74 years (65-94) with a male predominance (313 males, 65.0%) and median tumour thickness of 1.90 mm (IQR = 0.40-2.90, T1 = 33%, T2 = 20%, T3 = 24%, T4 = 23%). Inadequate surgical margins of excision (<10 mm) were common in older patients independent of site, thickness and ulceration (OR = 1.04, 95%CI = 1.00-1.07, p = 0.038). Inadequate excision margins were strongly associated with time to local recurrence, independent of age, thickness, ulceration and mitotic rate (HR = 3.00, 95%CI = 1.49-6.03, p = 0.0021), but not time to progression (p = 0.10) or disease specific survival (DSS, p = 0.27). Overall survival (OS) was strongly related to increasing age (HR = 1.04, 95%CI = 1.01-1.07, p = 0.015) and comorbid medical conditions (HR = 1.26, 95%CI = 1.12-1.42, p < 0.001), as assessed by the Charlson comorbidity index (CCI). DSS was significantly related to CCI (HR = 1.20, 95%CI = 1.01-1.42, p = 0.041) and not age (p = 0.46), when adjusting for thickness, ulceration and mitotic rate on multivariate analysis. CONCLUSION: Older patients present with poor prognosis melanomas yet are less likely to receive adequate surgical excision margins resulting in higher rates of local recurrence. In melanoma patients ≥65 years, the increasing number of medical comorbidities explains much of the age related variations in OS and DSS and should be considered when planning treatment.

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density.

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

Effects of Tamoxifen and oestrogen on histology and radiographic density in high and low mammographic density human breast tissues maintained in murine tissue engineering chambers.

Mammographic density (MD) is a strong risk factor for breast cancer. It is altered by exogenous endocrine treatments, including hormone replacement therapy and Tamoxifen. Such agents also modify breast cancer (BC) risk. However, the biomolecular basis of how systemic endocrine therapy modifies MD and MD-associated BC risk is poorly understood. This study aims to determine whether our xenograft biochamber model can be used to study the effectiveness of therapies aimed at modulating MD, by examine the effects of Tamoxifen and oestrogen on histologic and radiographic changes in high and low MD tissues maintained within the biochamber model. High and low MD human tissues were precisely sampled under radiographic guidance from prophylactic mastectomy fresh specimens of high-risk women, then inserted into separate vascularized murine biochambers. The murine hosts were concurrently implanted with Tamoxifen, oestrogen or placebo pellets, and the high and low MD biochamber tissues maintained in the murine host environment for 3 months, before the high and low MD biochamber tissues were harvested for histologic and radiographic analyses. The radiographic density of high MD tissue maintained in murine biochambers was decreased in Tamoxifen-treated mice compared to oestrogen-treated mice (p = 0.02). Tamoxifen treatment of high MD tissue in SCID mice led to a decrease in stromal (p = 0.009), and an increase in adipose (p = 0.023) percent areas, compared to placebo-treated mice. No histologic or radiographic differences were observed in low MD biochamber tissue with any treatment. High MD biochamber tissues maintained in mice implanted with Tamoxifen, oestrogen or placebo pellets had dynamic and measurable histologic compositional and radiographic changes. This further validates the dynamic nature of the MD xenograft model, and suggests the biochamber model may be useful for assessing the underlying molecular pathways of Tamoxifen-reduced MD, and in testing of other pharmacologic interventions in a preclinical model of high MD.

Mammographic density-a review on the current understanding of its association with breast cancer.

There has been considerable recent interest in the genetic, biological and epidemiological basis of mammographic density (MD), and the search for causative links between MD and breast cancer (BC) risk. This report will critically review the current literature on MD and summarize the current evidence for its association with BC. Keywords 'mammographic dens*', 'dense mammary tissue' or 'percent dens*' were used to search the existing literature in English on PubMed and Medline. All reports were critically analyzed. The data were assigned to one of the following aspects of MD: general association with BC, its relationship with the breast hormonal milieu, the cellular basis of MD, the generic variations of MD, and its significance in the clinical setting. MD adjusted for age, and BMI is associated with increased risk of BC diagnosis, advanced tumour stage at diagnosis and increased risk of both local recurrence and second primary cancers. The MD measures that predict BC risk have high heritability, and to date several genetic markers associated with BC risk have been found to also be associated with these MD risk predictors. Change in MD could be a predictor of the extent of chemoprevention with tamoxifen. Although the biological and genetic pathways that determine and perhaps modulate MD remain largely unresolved, significant inroads are being made into the understanding of MD, which may lead to benefits in clinical screening, assessment and treatment strategies. This review provides a timely update on the current understanding of MD's association with BC risk.

Dynamic changes in high and low mammographic density human breast tissues maintained in murine tissue engineering chambers during various murine peripartum states and over time.

Mammographic density (MD) is a strong heritable risk factor for breast cancer, and may decrease with increasing parity. However, the biomolecular basis for MD-associated breast cancer remains unclear, and systemic hormonal effects on MD-associated risk is poorly understood. This study assessed the effect of murine peripartum states on high and low MD tissue maintained in a xenograft model of human MD. Method High and low MD human breast tissues were precisely sampled under radiographic guidance from prophylactic mastectomy specimens of women. The high and low MD tissues were maintained in separate vascularised biochambers in nulliparous or pregnant SCID mice for 4 weeks, or mice undergoing postpartum involution or lactation for three additional weeks. High and low MD biochamber material was harvested for histologic and radiographic comparisons during various murine peripartum states. High and low MD biochamber tissues in nulliparous mice were harvested at different timepoints for histologic and radiographic comparisons. Results High MD biochamber tissues had decreased stromal (p = 0.0027), increased adipose (p = 0.0003) and a trend to increased glandular tissue areas (p = 0.076) after murine postpartum involution. Stromal areas decreased (p = 0.042), while glandular (p = 0.001) and adipose areas (p = 0.009) increased in high MD biochamber tissues during lactation. A difference in radiographic density was observed in high (p = 0.0021) or low MD biochamber tissues (p = 0.004) between nulliparous, pregnant and involution groups. No differences in tissue composition were observed in high or low MD biochamber tissues maintained for different durations, although radiographic density increased over time. Conclusion High MD biochamber tissues had measurable histologic changes after postpartum involution or lactation. Alterations in radiographic density occurred in biochamber tissues between different peripartum states and over time. These findings demonstrate the dynamic nature of the human MD xenograft model, providing a platform for studying the biomolecular basis of MD-associated cancer risk.

High and low mammographic density human breast tissues maintain histological differential in murine tissue engineering chambers.

Mammographic density (MD) is the area of breast tissue that appears radiologically white on mammography. Although high MD is a strong risk factor for breast cancer, independent of BRCA1/2 mutation status, the molecular basis of high MD and its associated breast cancer risk is poorly understood. MD studies will benefit from an animal model, where hormonal, gene and drug perturbations on MD can be measured in a preclinical context. High and low MD tissues were selectively sampled by stereotactic biopsy from operative specimens of high-risk women undergoing prophylactic mastectomy. The high and low MD tissues were transferred into separate vascularised biochambers in the groins of SCID mice. Chamber material was harvested after 6 weeks for histological analyses and immunohistochemistry for cytokeratins, vimentin and a human-specific mitochondrial antigen. Within-individual analysis was performed in replicate mice, eliminating confounding by age, body mass index and process-related factors, and comparisons were made to the parental human tissue. Maintenance of differential MD post-propagation was assessed radiographically. Immunohistochemical staining confirmed the preservation of human glandular and stromal components in the murine biochambers, with maintenance of radiographic MD differential. Propagated high MD regions had higher stromal (p = 0.0002) and lower adipose (p = 0.0006) composition, reflecting the findings in the original human breast tissue, although glands appeared small and non-complex in both high and low MD groups. No significant differences were observed in glandular area (p = 0.4) or count (p = 0.4) between high and low MD biochamber tissues. Human mammary glandular and stromal tissues were viably maintained in murine biochambers, with preservation of differential radiographic density and histological features. Our study provides a murine model for future studies into the biomolecular basis of MD as a risk factor for breast cancer.

Reorganization of vascular care in Canada.

The management of vascular disease requires knowledge of clinical assessment, pharmacotherapeutics, endovascular procedures and vascular surgery. In Canada, interventional cardiology, vascular surgery, interventional radiology and neurosurgery specialists may be involved in the care of patients with vascular disease, and they all claim to have expertise and an advantage in treating specific patients. The present article identifies the sources of the potential 'turf war' in vascular medicine, and proposes some possible solutions through reorganization of vascular care, with particular reference to the modern era of Canadian medicine.

Primary tumour expression of the cysteine cathepsin inhibitor Stefin A inhibits distant metastasis in breast cancer.

Using the clinically relevant 4T1-derived syngeneic murine model of spontaneous mammary metastasis to bone, we have identified the cysteine cathepsin inhibitor Stefin A as a gene differentially expressed in primary and metastatic mammary tumours. In primary tumours, Stefin A expression correlated inversely with metastatic potential in 4T1-derived lines and was not detected in tumour cells in culture, indicating induction only within the tumour microenvironment. Enforced expression of Stefin A in the highly metastatic 4T1.2 cell line significantly reduced spontaneous bone metastasis following orthotopic injection into the mammary gland. Consistent with the mouse data, Stefin A expression correlated with disease-free survival (absence of distant metastasis) in a cohort of 142 primary tumours from breast cancer patients. This was most significant for patients with invasive ductal carcinoma expressing Stefin A, who were less likely to develop distant metastases (log rank test, p = 0.0075). In a multivariate disease-free survival analysis (Cox proportional hazards model), Stefin A expression remained a significant independent prognostic factor in patients with invasive ductal carcinoma (p = 0.0014), along with grade and progesterone receptor (PR) status. In human lung and bone metastases, we detected irregular Stefin A staining patterns, with expression often localizing to micrometastases (<0.2 mm) in direct contact with the stroma. We propose that Stefin A, as a cysteine cathepsin inhibitor, may be a marker of increased cathepsin activity in metastases. Using immunohistology, the cathepsin inhibitor was detected co-expressed with cathepsin B in lung and bone metastases in both the murine model and human tissues. We conclude that Stefin A expression reduces distant metastasis in breast cancer and propose that this may be due to the inhibition of cysteine cathepsins, such as cathepsin B.

Clinical, pathological and genetic features of women at high familial risk of breast cancer undergoing prophylactic mastectomy.

Prophylactic mastectomy (PM) is a risk-management option for women at high familial risk of breast cancer (BC). This study describes the PM experience of women enrolled in a large observational cohort study involving families with a history of hereditary breast cancer. Within 357 multiple-case BC families [119 (33%) BRCA1 or BRCA2 mutation positive], identified via family cancer clinics, 49 cases of PM [21 (43%) BRCA1 or BRCA2 mutation positive] were identified and their clinical, pathological and genetic features reviewed. Families with at least one incidence of PM displayed stronger breast/ovarian cancer histories than did families without PM. Median age at time of PM was 45 years (range 28-58). Ten cases (21%) were bilateral PMs in unaffected women and 39 cases were contralateral PMs in women with prior invasive BC (71%) or ductal carcinoma in situ (DCIS) (8%). Most (88%) underwent total mastectomy. Unnecessary axillary surgery occurred in eight subjects (16%). Malignant histology was found in three PM specimens (6%). Prior to genetic testing, PM was performed in two women who were subsequently shown not to carry the mutation specific to their family. Optimal utilization of genetic testing to guide surgical decision making, appropriate surgical technique and careful pathology examination of PM specimens, are important issues to consider prior to PM in women at high familial risk of BC.

Radical surgery with omental flap for uncontrolled locally recurrent breast cancer.

BACKGROUND: Uncontrolled chest wall disease due to breast cancer is a highly morbid condition causing pain, ulceration, malodour and the need for frequent dressings. Aggressive surgical approaches are rarely justified because most patients will succumb to metastatic breast cancer within a short period. A highly selected group of patients with minimal or no evidence of metastatic disease and good performance status may benefit from radical chest wall surgery. Omental transposition flaps are ideal for reconstructing extensive surgical defects following chest wall surgery. METHODS: A retrospective review was carried out of 61 female patients treated consecutively between 1980 and 1995. The surgical technique is described herein. RESULTS: All patients were symptomatic preoperatively. Symptoms included ulceration (80%), pain (44%) and malodour (40%). Twenty-nine patients had uncontrolled local recurrence following initial treatment for locally advanced breast cancer and 32 patients developed uncontrolled recurrence after treatment for operable breast cancer by mastectomy or conservation surgery. Median survival following chest wall surgery was 21 months and the median local recurrence-free interval was 20 months. Morbidity was -limited. There were no cases of major flap loss. Twenty-nine patients (48%) had no further local disease. Eighteen patients (30%) developed soft-tissue recurrence at the edge of the omental flap or in surrounding skin and 14 (23%) developed recurrence beneath the flap. CONCLUSION: In a highly selected group of patients with symptomatic uncontrolled chest wall recurrence who are fit and have an expectation of at least moderate-term survival, radical chest wall surgery and omental flap transposition offers excellent palliation and local control in the majority of patients

Isolated limb infusion for melanoma: a simple alternative to isolated limb perfusion.

OBJECTIVE: To describe initial experience with the new technique of isolated limb infusion (ILI) for in-transit melanoma. DESIGN: A prospective case series. SETTING: The major tertiary care oncology centre for the state of Victoria, Australia. PATIENTS: Nine patients having for extensive in-transit limb melanoma INTERVENTIONS: All patients received ILI (13 treatments). OUTCOME MEASURES: Patient survival, response to treatment and complications of treatment. RESULTS: There were no perioperative deaths and morbidity was limited to deep venous thrombosis and pulmonary embolism in 1 patient. Control of the in-transit metastases was achieved to some degree in all patients and was complete in 4. CONCLUSIONS: ILI is an alternative treatment modality for patients suffering from multiple, advanced in-transit melanoma metastases. It provides effective palliation with limited morbidity and offers a safe, quick, inexpensive alternative to isolated limb perfusion with comparable results.

Tubular carcinoma of the breast: prognosis and response to adjuvant systemic therapy.

BACKGROUND: Tubular carcinoma of the breast is an uncommon and usually small tumour, and is thought to have a favourable prognosis. The present study examined the long-term prognosis of patients with tubular breast carcinoma and the roles of axillary dissection and adjuvant therapy. METHODS: Eighty-six tubular cases were identified from a large worldwide database of 9520 breast carcinoma patients entered into randomized adjuvant therapy trials run by the International Breast Cancer Study Group from 1978 to 1999. These patients were followed for a median of 12 years. RESULTS: Forty-two (49%) cases were node-positive, of which 33 (79%) had 1-3 nodes involved. Ten (32%) of the 31 smaller tumours (< or = 1 cm in size) were node-positive. Patients with node-positive tubular carcinoma had a significantly better 10-year relapse-free survival (P = 0.006) and survival (P < 0.0001) compared with non-tubular node-positive cases. Overall survival was similar for node-positive and node-negative tubular carcinoma. Overall, 71 patients (83%) received some form of adjuvant systemic therapy. Of the 86 cases, 43 (50%) received more than one course of chemotherapy. There was an 85% decrease in the risk of death for patients who received more than one course of chemotherapy compared to those who did not (hazard ratio 0.15, 95% confidence interval (CI): 0.03-0.82; P = 0.03). CONCLUSIONS: Compared to other histological types of breast cancer, tubular carcinoma has a better long-term prognosis. Adjuvant chemotherapy may further improve prognosis and involvement of axillary nodes may not be an indicator for early death due to breast carcinoma.

Handheld gamma probe localization of accessory splenic tissue in recurrent idiopathic thrombocytopenic purpura.

Recurrent idiopathic thrombocytopenic purpura due to residual splenic tissue after splenectomy is uncommon. Location of the offending splenic tissue can be technically demanding. A small accessory spleen was localized intraoperatively with a handheld gamma probe after standard technetium-labeled heat-damaged red blood cell scan of the liver and spleen.

Urokinase plasminogen activator system gene expression is increased in human breast carcinoma and its bone metastases--a comparison of normal breast tissue, non-invasive and invasive carcinoma and osseous metastases.

The urokinase plasminogen activator (uPA) system has been widely associated with the development of breast carcinoma. However, the role of the urokinase pathway in the development of osseous breast cancer metastases has been largely overlooked. We studied the expression of uPA, urokinase plasminogen activator receptor (uPAR)- and plasminogen activator inhibitor type-1 (PAI-1) in human breast carcinomas and their bone metastases, using in situ hybridisation. Studies were performed using paraffin-embedded tissue from 13 ductal carcinomas, 23 invasive ductal carcinomas, five normal breasts and 25 bone metastases. The majority of the tumours examined expressed low to moderate levels of uPA mRNA and low to high levels of uPAR and PAI-1 mRNA, which was predominantly localised to the epithelial tumour cells. There was slight over-expression of uPA and PAI-1 mRNA and a marked increase in uPAR mRNA expression in the malignant tumours compared with benign tissue. Overall, uPAR and PAI-1 mRNA expression was found to be more variable than uPA mRNA, suggesting a possible role of the receptor and inhibitor in the regulation of uPA activity. Increased alpha1(I) procollagen (COL) and osteopontin (OPN) mRNA expression was detected, primarily in the stromal cells, in malignant tumours compared with the benign tissue. The increased expression of the components of the uPA system on the epithelial tumour cells may account for the activation of the proteolytic cascade that occurs during breast cancer metastasis to bone. Furthermore, the over-expression of COL and OPN suggests a possible interaction between these matrix proteins and the uPA system.

Axillary dissection and ductal carcinoma in situ of the breast: a change in practice.

BACKGROUND: Axillary dissection may be associated with significant morbidity and, while it is necessary in the treatment of invasive breast cancer, is not indicated for the treatment of pure ductal carcinoma in situ (DCIS), although it is being performed in a significant number of cases. The present study examined the incidence of elective axillary dissection in the treatment of DCIS cases detected in a mammographic screening programme over a 4-year period, and whether surgeons have changed their practice in this respect. METHODS: BreastScreen Victoria records were examined retrospectively for the period from January 1995 to December 1998 to identify patients treated for DCIS. The incidence and indications for axillary surgery were investigated. RESULTS: There were 579 cases of DCIS and 93 (16%) had some form of axillary surgery, which was thought to be inappropriate in 57 (10%), the latter being performed by 21 city surgeons and 20 rural surgeons. Before surgery, 36 (63%) cases were diagnosed by core biopsy or excision, and 21 (37%) had imaging and cytology alone for diagnosis. The rate of unnecessary axillary dissections dropped steadily from 14% in 1995 to 4% in 1998, a significant reduction (P = 0.01). CONCLUSION: The incidence of axillary dissection for DCIS has dropped significantly over the last 4 years in Victoria, possibly due to increased awareness through education and guidelines. Surgeons are now more aware that in situ lesions do not need axillary dissection, and that axillary dissection should not be performed for breast cancer unless invasion has been proved histologically.

Tumor cells are the source of osteopontin and bone sialoprotein expression in human breast cancer.

Bone sialoprotein (BSP) and osteopontin (OPN) are secreted glycoproteins with a conserved Arg-Gly-Asp (RGD) integrin-binding motif and are expressed predominantly in bone. The RGD tripeptide is commonly present in extracellular attachment proteins and has been shown to mediate the attachment of osteosarcoma cells and osteoclasts. To determine the origin and incidence of BSP and OPN mRNA expression in primary tumor, a cohort of archival, primary invasive breast carcinoma specimens was analyzed. BSP transcripts were detected in 65% and OPN transcripts in 77% of breast cancers examined. In general, BSP and OPN transcripts were detected in both invasive and in situ carcinoma components. The transcripts were not detected in surrounding stromal cells or in peritumoral macrophages. Despite its abundance in carcinomas, BSP expression was not detected in a panel of 11 human breast cancer cell lines (MCF-7, T47D, SK-Br-3, MDA-MB-453, MDA-MB-231, MDA-MB-436, BT549, MCF-7ADR, Hs578T, MDA-MB-435, and LCC15-MB) and OPN expression was detected only in two of these (MDA-MB-435 and LCC15-MB). To examine the possibility that expression of these genes was down-regulated in cell culture, several cell lines were grown as nude mouse xenografts in vivo; however, these tumors also failed to express BSP. OPN expression was identified in all cell lines grown as nude mouse xenografts. Our data suggest that in human primary breast tumors, the origin of BSP and OPN mRNA is predominantly the breast cancer cells and that expression of these transcripts is influenced by the tumor environment.