Optimal systemic therapy for early breast cancer in women: a clinical practice guideline

The Breast Cancer Disease Site Group of Cancer Care Ontario identified the need for new guidelines for the adjuvant systemic therapy of early-stage breast cancer. The specific question to be addressed was "What is the optimal adjuvant systemic therapy for female patients with early-stage operable breast cancer, when patient and disease factors are considered?" A systematic review was prepared based on literature searches conducted using the medline and embase databases for the period January 2008 to March 5, 2012, and updated to May 12, 2014. Guidelines were located from that search, from the Standards and Guidelines Evidence directory of cancer guidelines, and from the Web sites of major guideline organizations. The literature located was subdivided into the broad categories of chemotherapy, hormonal therapy, and therapy targeted to her2 (human epidermal growth factor receptor 2). Although several of the systemic therapies discussed in this guideline can be considered in the neoadjuvant setting, the review focused on trials with rates of disease-free and overall survival as endpoints and thus excluded several trials that used pathologic complete response as a primary endpoint. Based on the systematic review, the working group drafted recommendations on the use of chemotherapy, hormonal therapy, and targeted therapy; based on their professional experience, they also drafted recommendations on patient and disease characteristics and recurrence risk. The literature review and draft recommendations were circulated to a consensus panel of medical oncologists who had expertise in breast cancer and who represented the regions of Ontario. Items without initial consensus were discussed at an in-person consensus meeting held in Toronto, November 23, 2012. The final recommendations are those for which consensus was reached before or at the meeting. Some of the key evidence was revised after the updated literature search. Evidence reviews for systemic chemotherapy, endocrine therapy, and targeted therapy for her2-positive disease are reported in separate articles in this supplement. The full three-part 1-21 evidence-based series, including complete details of the development and consensus processes, can be found on the Cancer Care Ontario Web site at https://www.cancercare.on.ca/toolbox/qualityguidelines/diseasesite/breast-ebs.

Novel agents and associated toxicities of inhibitors of the pi3k/Akt/mtor pathway for the treatment of breast cancer

The pi3k/Akt/mtor (phosphatidylinositol 3 kinase/ Akt/mammalian target of rapamycin) signalling pathway is an established driver of oncogenic activity in human malignancies. Therapeutic targeting of this pathway holds significant promise as a treatment strategy. Everolimus, an mtor inhibitor, is the first of this class of agents approved for the treatment of hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer. Everolimus has been associated with significant improvements in progression-free survival; however, it is also associated with increased toxicity related to its specific mechanism of action.

METHODS

A comprehensive review of the literature conducted using a focused medline search was combined with a search of current trials at http://ClinicalTrials.gov/. Summary tables of the toxicities of the various classes of pi3k/Akt/mtor inhibitors were created. A broad group of Canadian health care professionals was assembled to review the data and to produce expert opinion and summary recommendations for possible best practices in managing the adverse events associated with these pathway inhibitors.

RESULTS

Differing toxicities are associated with the various classes of pi3k/Akt/mtor pathway inhibitors. The most common unique adverse events observed in everolimus clinical trials in breast cancer include stomatitis (all grades: approximately 60%), noninfectious pneumonitis (15%), rash (40%), hyperglycemia (15%), and immunosuppression (40%). To minimize grades 3 and 4 toxicities and to attempt to attain optimal outcomes, effective management of those adverse events is critical. Management should be interdisciplinary and should use approaches that include education, early recognition, active intervention, and potentially prophylactic strategies.

DISCUSSION

Everolimus likely represents the first of many complex oral targeted therapies for the treatment of breast cancer. Using this agent as a template, it is essential to establish best practices involving and integrating multiple disciplines for the management of future pi3k/Akt/mtor signalling pathway inhibitors.

Investigation of prolonged hypobaric hypoxia-induced change in rat brain using T2 relaxometry and diffusion tensor imaging at 7T

The present study examines the change in water diffusion properties of the corpus callosum (CC) and the hippocampus, in response to prolonged hypobaric hypoxia (HH) stress, using in vivo magnetic resonance imaging (MRI) modalities such as T2 relaxometry and diffusion tensor imaging (DTI). Three groups of rats (n=7/group) were exposed to a simulated altitude of 6700m above sea level for the duration of 7, 14 and 21days, respectively. Data were acquired pre-exposure, post-exposure and after 1week of normoxic follow-up in each group. The increment in T2 values with no apparent diffusion coefficient (ADC) change in the CC after 7 and 14days of HH exposure indicated mixed (vasogenic and cytotoxic) edema formation. After 1week of normoxia, 7-day HH-exposed rats showed a decrease in ADC values in the CC, probably due to cytotoxic edema. A delayed decrease in ADC values was observed in the hippocampus after 1week normoxic follow-up in 7- and 14-day HH groups giving an insight of cytotoxic edema formation. Interestingly, 21-day HH-exposed rats did not show change in ADC values. The decrease in T2 values after 14 and 21days in the hippocampal region depicts iron deposition, which was confirmed by histopathology. This study successfully demonstrated the use of MRI modality to trace water diffusion changes in the brain due to prolonged HH exposure.

Oculoleptomeningeal Amyloidosis associated with transthyretin Leu12Pro in an African patient

Oculoleptomeningeal amyloidosis is a rare manifestation of hereditary transthyretin (TTR) amyloidosis. Here, we present the first case of leptomeningeal amyloidosis associated with the TTR variant Leu12Pro mutation in an African patient. A 43-year-old right-handed Nigerian man was referred to our centre with rapidly progressive neurological decline. He presented initially with weight loss, confusion, fatigue, and urinary and erectile dysfunction. He then suffered recurrent episodes of slurred speech with right-sided weakness. He went on to develop hearing difficulties and painless paraesthesia. Neurological examination revealed horizontal gaze-evoked nystagmus, brisk jaw jerk, increased tone, brisk reflexes throughout and bilateral heel-shin ataxia. Magnetic resonance imaging showed extensive leptomeningeal enhancement. Cerebrospinal fluid analysis showed a raised protein of 6.4 g/dl. Nerve conduction studies showed an axonal neuropathy. Echocardiography was characteristic of cardiac amyloid. TTR gene sequencing showed that he was heterozygous for the leucine 12 proline mutation. Meningeal and brain biopsy confirmed widespread amyloid angiopathy. TTR amyloidosis is a rare cause of leptomeningeal enhancement, but should be considered if there is evidence of peripheral or autonomic neuropathy with cardiac or ocular involvement. The relationship between different TTR mutations and clinical phenotype, disease course, and response to treatment remains unclear.

Unravelling mitochondrial pathways to Parkinson's disease

Mitochondria are essential for cellular function due to their role in ATP production, calcium homeostasis and apoptotic signalling. Neurons are heavily reliant on mitochondrial integrity for their complex signalling, plasticity and excitability properties, and to ensure cell survival over decades. The maintenance of a pool of healthy mitochondria that can meet the bioenergetic demands of a neuron, is therefore of critical importance; this is achieved by maintaining a careful balance between mitochondrial biogenesis, mitochondrial trafficking, mitochondrial dynamics and mitophagy. The molecular mechanisms that underlie these processes are gradually being elucidated. It is widely recognized that mitochondrial dysfunction occurs in many neurodegenerative diseases, including Parkinson's disease. Mitochondrial dysfunction in the form of reduced bioenergetic capacity, increased oxidative stress and reduced resistance to stress, is observed in several Parkinson's disease models. However, identification of the recessive genes implicated in Parkinson's disease has revealed a common pathway involving mitochondrial dynamics, transport, turnover and mitophagy. This body of work has led to the hypothesis that the homeostatic mechanisms that ensure a healthy mitochondrial pool are key to neuronal function and integrity. In this paradigm, impaired mitochondrial dynamics and clearance result in the accumulation of damaged and dysfunctional mitochondria, which may directly induce neuronal dysfunction and death. In this review, we consider the mechanisms by which mitochondrial dysfunction may lead to neurodegeneration. In particular, we focus on the mechanisms that underlie mitochondrial homeostasis, and discuss their importance in neuronal integrity and neurodegeneration in Parkinson's disease.

A rare conglomeration of neurovascular variations in the brachium-antebrachium: clinico-embryological elucidation

During routine dissection in left upper limb in an elderly male cadaver, variations in the arterial and neural pattern were noticed. The undersized brachial artery divided terminally into radial and ulnar artery at a distance of 15.4 cm from the tip of coracoid process, proximal to its usual division in cubital fossa. Additionally, the superior and inferior ulnar collateral artery instead of arising from the brachial artery, emanated from ulnar artery. The course of the median nerve also deserves a brief mention as it crossed the brachial artery from medial to lateral side to position itself laterally in the midbrachium. Coursing further, it shifted from lateral to medial side over the ulnar artery in the distal third of arm, thus placing itself medial to ulnar artery in the cubital fossa. There was also a communication between a medial offshoot of the musculocutaneous nerve and the median nerve 3 cm from the bifurcation of the brachial artery. Although the variations in the origin, termination, course and branching pattern of upper limb vessels and nerves are well documented, but the multitude of disparity in morphology with confusing neurovascular assembly put together in the same limb denotes an outstanding case. An attempt has been made to correlate the present anatomical variations with embryological aspects. Moreover, the clinical inferences of such variations are discussed for planning, performing and analyzing invasive and noninvasive clinical procedures in this region.

Posterior reversible encephalopathy syndrome in children with kidney disease

Posterior reversible encephalopathy syndrome (PRES) is a clinic-radiographic entity of heterogeneous etiologies that are grouped together because of similar findings on neuro-imaging and associated symptom complex of headache, vision loss, altered mentation, and seizures. Although usually considered benign and reversible, characteristics of this syndrome in pediatric patients remain obscure. This case series included 11 patients (8 males, 3 females, age 3-15 years) of PRES during September 2010 to February 2012 out of a total 660 renal pediatric patients (1.66%). We studied their clinical profile, contributory factors, and outcome. Presenting symptoms were headache in 73%, dimness of vision or cortical blindness in 36%, seizures in 91%, and altered mentation in 55%. The associated renal diseases were acute renal failure (55%), chronic renal failure (9%), and 36% had normal renal function. The contributory factors were uncontrolled hypertension (100%), severe hypoproteinemia (9%), persistent hypocalcemia (9%), hemolytic uremic syndrome (36%), cyclosporine toxicity (9%), lupus nephritis (9%), high hematocrit (9%), and pulse methylprednisolone (9%). Brain imaging showed involvement of occipito-parietal area (100%) and other brain areas (63%). All but one patient of hemolytic uremic syndrome had complete clinical neurological recovery in a week, and all had normal neurological imaging after 4-5 weeks. PRES is an underdiagnosed entity in pediatric renal disease patients. Associated hypertension, renal disease, and immunosuppressive treatment are important triggers. Early diagnosis and treatment of comorbid conditions is of prime importance for early reversal of syndrome.

An unusual array of extensor musculature and tendons of the hand clinico-anatomical insight

Extensor tendon injury is a frequent finding in clinical practice. During a routine dissection class of undergraduate medical students examining the extensor aspect of the right hand, they found an interesting pattern of extensor tendons. The extensor digitorum (ED) exhibited three tendons for the middle and ring fingers. The intermediate tendon of the ED was found to pass to the junctura connecting the tendons of the ring and middle fingers. Additionally the Extensor carpi ulnaris displayed two tendinus slips. The lateral slip was inserted on the base of fifth metacarpal as usual, whereas the medial slip divided into two strands- proximal and distal. Apart from the above findings in the current case specimen, there was an accessory muscle belly for the index finger and the extensor digiti minimi bifurcated into two tendinus slips which gained attachment to the dorsal digital expansion of the little finger. These accessory muscle bellies and tendons could possibly be utilized for tendon reconstructions such as repairs, tenoplasties or tendon transfers.

Outcomes of her2-positive early-stage breast cancer in the trastuzumab era: a population-based study of Canadian patients

Breast cancer is heterogenous, with variable expression of the estrogen receptor (er), progesterone receptor (pr), and human epidermal growth factor receptor 2 (her2). Overexpression of her2 is generally considered a negative prognostic feature, but whether outcomes for her2-positive early breast cancer remain different from those for other subtypes in the era of trastuzumab-based adjuvant therapy is unknown.

METHODS

Using a retrospective chart review, we compared overall survival (os) and relapse-free survival (rfs) in 3 groups of patients with early-stage breast cancer: er-positive or pr-positive (or both) and her2-negative ["hormone receptor-positive" (hr+)]; her2-positive (her2+); and er-negative, pr-negative, and her2-negative ["triple-negative" (tn)].

RESULTS

In the 503 charts analyzed (332 hr+, 94 her2+, 77 tn), the 5-year os and rfs were, respectively, 94.2% and 87.2% for hr+ patients, 88.6% and 74.9% for her2+ patients, and 85.4% and 76.2% for tn patients. On multivariate analysis, the os for the her2+ subtype was similar to that for the hr+ subtype (hazard ratio:1.07; 95% confidence interval: 0.31 to 3.67 with hr+ as reference), but os was significantly worse for tn patients than for hr+ patients (hazard ratio: 4.37; 95% confidence interval: 1.56 to 12.24). In her2+ patients, the 5-year os and rfs trended better for patients with er+ or pr+ disease than for patients with er-negative and pr-negative disease (5-year os: 92.1% vs. 86.9%; 5-year rfs: 79.8% vs. 71.4%). Of her2+ patients, just 80.9% received trastuzumab, including 33.3% of her2+ patients with sub-centimetre tumours.

CONCLUSIONS

In the trastuzumab era, patients with her2+ and hr+ early breast cancer have similar outcomes, while tn patients experience a significantly worse os than either of the foregoing groups. Outcomes for her2+ patients may differ by er and pr status. Trastuzumab was underutilized in this cohort.

Meta-analysis: colonoscopic post-polypectomy bleeding in patients on continued clopidogrel therapy

BACKGROUND

Current guidelines recommend the cessation of clopidogrel therapy 5 days and 7-10 days prior to colonoscopic polypectomy. Recent studies have advocated for continued clopidogrel as post-polypectomy bleeding (PPB) rates have been similar to those in the general population not on antithrombotic therapy.

AIM

To assess colonoscopic post-polypectomy bleeding in patients on continued clopidogrel therapy.

METHODS

A literature search was conducted for studies that investigated PPB in patients on continued clopidogrel therapy. The primary outcome of interest was the pooled relative risk ratio (RR) of colonoscopic PPB in patients on continued clopidogrel therapy vs. controls. Secondary outcomes were a comparison of immediate and delayed colonoscopy PPB in patients on continued clopidogrel therapy vs. controls.

RESULTS

Five observational studies included 574 subjects on continued clopidogrel therapy and 6169 control subjects. The pooled RR for PPB on continued clopidogrel therapy was 2.54 (95% CI 1.68-3.84, P < 0.00001). For immediate PPB there was a nonsignificant pooled RR of 1.76 (95% CI 0.90-3.46, P = 0.10), and delayed PPB there was a significant pooled RR of 4.66 (95% CI 2.37-9.17, P < 0.00001).

CONCLUSIONS

The results of this meta-analysis suggest that continued clopidogrel increases the risk of delayed but not immediate post-polypectomy bleeding. Clopidogrel interruption in individuals with coronary artery disease predisposes to serious acute ischaemic events. In high-risk patients, endoscopists should be cognisant of these risks and consider deferring elective colonoscopy and polypectomy until it is considered safe to interrupt clopidogrel therapy.

Retroaortic left renal vein associated with unilateral superior renal polar artery: a clinico-embryological perspective

The aim of the current study is to report an unusual occurrence of a retroaortic left renal vein in an adult male cadaver of Caucasian origin. This unusual variant was discovered during the course of preclinical educational training programme for undergraduate medical students. The vascular anomaly was dissected and the surrounding adnexa carefully studied for associated variations. Subsequently, morphometry was performed on the specimen to measure certain important parameters. The left renal vein was found to emerge from lower part of renal hilum and traversed posterior to abdominal aorta and finally terminated into Inferior vena cava. Additionally, the left renal artery was higher in position and originated from the abdominal aorta at the level of upper border of body of Ist lumbar vertebra. This type of anomaly is very important as it may be associated with varicocoele. Furthermore, in preoperative planning for nephrectomy, partial nephrectomy and living donor nephrectomy, the surgeons should keep in mind the possibility of this vascular anomaly. It is also stated that left renal vein appears to be at the centre of a huge venous network which makes the nephrectomy hazardous and permits the spread of infectious material and neoplasms.

Chronic type B aortic dissection in association with Hemolyticuremic syndrome in a child

Aortic dissection (AD) is a potentially life-threatening medical emergency usually encountered in the elderly. Here, we report a 9-year-old child who was incidentally detected to have asymptomatic chronic type B dissecting aneurysm of aorta when he presented with relapse of Hemolytic uremic syndrome (HUS) without any genetic abnormalities like Marfan or Ehler-Danlos syndrome. To the best of our knowledge, this is the first case of AD associated with HUS in a child without any known associated genetic or inherited risk factors.

Abstract P4-16-14: Salvage Radiotherapy and Cisplatin for Triple Negative Breast Cancer: A Multi-Centre Study

Background/Rationale: Patients with locally advanced, triple negative(TN) breast cancer may undergo neo-adjuvant chemotherapy(NAC) prior to definitive surgery. For tumours that demonstrate progression during NAC or rapid recurrence, the optimal second-line or ‘salvage’ therapy is not well defined.

Purpose: To examine the efficacy and toxicity of salvage radiotherapy (XRT) and Cisplatin(CDDP) in patients with locally advanced, triple-negative breast cancer.

Methods: A retrospective review of LABC databases was performed at 3 quaternary cancer centres to identify patients with TN disease who had salvage XRT +/− CDDP. (Local research ethics board approval was obtained at each centre independently.) Patient demographics, initial staging information and primary pathology reports were reviewed to confirm eligibility. Details of NAC and salvage treatments were collected. Clinical tumour response was determined by physical assessments and imaging and categorized retrospectively using standardized definitions of response and progression. Pathological response was evaluated in all cases if available. Toxicity, loco-regional control, distant disease progression and survival were assessed up to the last available follow-up and reported. Patients who underwent previous XRT were excluded.

Results: 12 patients who underwent salvage treatment were identified. All patients had TN, LABC, including 10 patients with invasive ductal carcinoma; 1 metaplastic carcinoma; 1 poorly differentiated carcinoma with neuroendocrine features. The most common indications for salvage treatment were tumour progression during NAC (n = 6) and loco-regional recurrence shortly after NAC and mastectomy (n = 3). The median age was 48 (range, 30–85). 9 patients underwent concurrent XRT + CDDP; 3 patients had salvage radiotherapy only due to poor performance status or co-morbidities. Cisplatin was administered weekly, median dose was 30mg/m2 (range, 25–40mg/m2). Median XRT dose was 65 Gy (range, 50–70 Gy) with 5 patients receiving a BID hyper-fractionated regimen. The median follow-up duration was 8 months (range, 2–60 months). 11 of 12 patients demonstrated a partial or complete clinical response to XRT +/− CDDP. 4 out of 8 patients who had surgery following salvage treatment achieved a complete pathological response (pCR). All patients developed grade 2 or 3 radiation dermatitis. No grade 4–5 toxicity was observed. One patient missed one cycle of CDDP due to grade 1 thrombocytopenia. At the last available follow-up, 4 patients were deceased or developed distant metastasis, 5 patients were alive with no evidence of disease, 3 patients had partial tumour response with surgery pending.

Conclusions: Patients with locally advanced, triple-negative breast cancer who progressed during or shortly after NAC had a high clinical response rate when treated with salvage XRT+ CDDP. In patients who underwent surgery after salvage treatment, 50% achieved pCR. Salvage treatments appeared to be relatively well tolerated and safe.

This subset of patients is at very high risk for tumour recurrence. Prospective, multi-centre studies of concurrent cisplatin and radiotherapy in the setting of locally advanced, triple negative breast cancer are needed to further assess efficacy and toxicity.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-16-14.

Extending Neoadjuvant Care through Multi-Disciplinary Collaboration: Proceedings from the Fourth Annual Meeting of the Canadian Consortium for Locally Advanced Breast Cancer

The use of systemic therapy before surgery (“neoadjuvant therapy”) is the standard of care for the treatment of locally advanced and nonoperable breast cancer. The advantages of neoadjuvant therapy include improved rates of breast-conserving surgery, the possibility of early measurement of response, and potentially improved outcomes for certain subgroups of high-risk patients. The use of neoadjuvant therapy in operable breast cancer is increasing, although there are no clear guidelines in Canada to help guide patient selection and management. Multidisciplinary experts in the diagnosis and treatment of locally advanced breast cancer (labc) converged at the fourth annual meeting of the Canadian Consortium for LABC (colab) to further their goals of improved standards for neoadjuvant care and clinical research through education and collaboration. Canadian clinical researchers were joined by Dr. Michael Untch of the Helios Hospital Berlin–Buch—representing the German neoadjuvant treatment groups German Gynecologic Oncology Working Group (Arbeitsgemeinschaft Gynakologische Onkologie) and German Breast Group—to discuss the advancement of research in the neoadjuvant setting and important issues of clinical care and investigator-led research. The group reached a consensus on the importance of multidisciplinary collaboration, the use of clips to mark tumour location, and core biopsy testing for the estrogen and progesterone receptors and the human epidermal growth factor receptor 2 at the time of diagnosis. Other initiatives—including creation of a prospective database, inception of the colab Neoadjuvant Network, and development of a clinical survey to evaluate current practice—continue to further the colab mandate of transforming the neoadjuvant treatment landscape in Canada.

P4-01-04: Effects of CYP2D6 Phenotype and Drug Adherence on Tamoxifen Metabolite Levels

Background

Although the activity of cytochrome P450 2D6 (CYP2D6), the enzyme responsible for conversion of tamoxifen (TAM) to its most important active metabolite endoxifen, varies significantly with genotype. Routine genotype testing in patients on TAM has recently been discouraged. Conflicting results in publications regarding the prognostic utility of this test remain unexplained. Confounding factors could be lack of predicted correlation between CYP2D6 genotype and TAM active metabolites, or variability of patient compliance

Methods: Consecutive breast cancer patients on TAM were asked to enroll in a study to examine the relationship between CYP 2D6 phenotype, patient-reported treatment adherence, and TAM metabolites levels. Patients were genotyped for CYP2D6 polymorphisms using long-range PCR allele-specific amplification and single-nucleotide primer extension assay. From the genotypes, four phenotype groups were defined: Ultra rapid Metabolizer (UM), Extensive Metabolizer (EM), Intermediate Metabolizer (IM) and Poor Metabolizer (PM). Plasma was collected after at least 6 weeks of TAM (20 mg daily). The parent drug TAM, as well as 4-hydroxy N-desmethyl tamoxifen (endoxifen), 4 hydroxy tamoxifen (4OHtam) and N-desmethyl-tamoxifen (NDtam), were determined by Liquid Chromatography tandem mass-spectrometry (LC-MS/MS). Patients also completed a questionnaire about ethinicity, side effects, concurrent medications and tamoxifen adherence. Correlation between metabolite/TAM ratio and phenotype was tested by Spearman correlation test. Relationship between metabolite levels and adherence was tested by Wilcoxon rank sum test. Chi square test was used to compare proportions.

Results: Of the 100 patients enrolled there were 62 Caucasians, 25 Asians, 4 Africans and 6 Unknown. We found a strong correlation between ratio of endoxifen/TAM and phenotype (p &lt;.0001) (Table 1) Over a 2 week period 68 never missed a TAM dose, 25 missed 1–2 times, 2 missed 3–5 times and 2 &gt; 5times (2 missing data). In EM group we found significantly lower levels of TAM (p &lt;.0001), NDtam (p=.008), 4OHtam (p=.003) in less adherent patients. A trend to decreased levels was also shown for endoxifen (p=.081). No associations were found between adherence or phenotype activity and side effects.