Energetic and myocellular pathways in cardiac and skeletal muscle following anthracycline chemotherapy

Background

Anthracycline-related cardiac dysfunction is a recognised consequence of cancer therapies. Here we assess resting cardiac and skeletal muscle energic status as an early mechanistic pathway of myocyte derangement and explore molecular targets of skeletal myocyte metabolism, protein synthesis/degradation and mitochondrial biogenesis signalling.

Methods

We conducted a prospective, mechanistic, observational, longitudinal study of chemotherapy-naive breast cancer patients undergoing anthracycline-based chemotherapy, compared to a healthy control group. 31P-Magnetic Resonance spectroscopy in cardiac and skeletal muscle (phosphocreatine/gamma adenosine triphosphate (PCr/yATP) and inorganic phosphate/phosphocreatine (Pi/PCr) ratios respectively), cardiac magnetic resonance (CMR) imaging inclusive of T1 and T2 mapping, echocardiography-derived global longitudinal strain function, serum NT-pro-BNP and skeletal muscle biopsies from the right vastus lateralis were assessed before and after 3 cycles of Flurouracil, Epirubicin and Cyclophosphamide followed by 3 cycles of Docetaxel. Statistical significance was set at p<0.05.

Results

Twenty-five female breast cancer patients (median age 53 years, range 32–74 years) receiving a mean epirubicin dose 307 mg/m2) and twenty-eight controls (median age 44 years, range 23–65) were recruited. All study assessments in breast cancer patients at pre-chemotherapy stage were comparable to the matched healthy controls. However, following chemotherapy, breast cancer patients demonstrated a small but significant reduction in cardiac function (global longitudinal strain −22.9±3.9 vs −19.1±3.3%, p=0.01 and CMR-derived ejection fraction 65±5 vs 62±4%, p=0.047), a mild increase in CMR-derived indexed left ventricular volumes (end diastolic 65±10 vs 74±11 ml/m2, p=0.014 and end systolic 23±5 vs 28±5 ml/m2, p=0.01) as well as an increase in left ventricular T1 and T2-mapping (1289±29 vs 1321±31 ms, p=0.004 and 50±4 vs 55±7 ms, p=0.027, respectively) and serum NT-Pro-BNP (49±25 vs 108±84 pg/m, p=0.008). After epirubicin, there was significant reduction in cardiac PCr/yATP ratio (2.0±0.7 vs 1.2±0.6, p=0.007) and a significant increase in skeletal muscle Pi/PCr ratio (0.13±0.04 vs 0.22±0.2, p=0.008) – Figure 1.

Following chemotherapy, there was significant upregulation of skeletal myocyte protein synthesis (mammalian target of rapamycin, 0.44±0.4 vs 0.53±0.2, p<0.001) and degradation (Calcium/calmodulin dependent protein kinase II, 1.4±0.7 vs 2.7±1.1, p<0.001), metabolism (peroxisome proliferator-activated receptor gamma, 0.35±0.2 vs 0.60±0.1, p<0.001) and muscle mass regulator myostatin-2 (0.16±0.1 vs 0.24±0.1, p<0.001).

Conclusion

Contemporary doses of epirubicin for breast cancer result in significant reduction of cardiac and skeletal muscle high energy 31P-metabolism alongside skeletal myocellular alterations of protein synthesis and metabolic regulation pathways.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Tenovus ScotlandNHS Grampian Endowment fund

Abstract P4-13-01: Oncoplastic breast conservations – The Scottish Audit: Surgical techniques, oncological outcomes, complication rates and variations in practice across the country based on the analysis of 589 patients

Introduction: current evidence for oncoplastic breast conservation (OBC) is based on single institutional series. We studied the outcomes of OBC practice in Scotland and compare individual breast units.

Methods: a predefined database of patients treated with OBC was completed retrospectively in 11 breast units in Scotland. Patients were treated with OBC from 2005 onwards were included. For statistical calculations Chi-test, ANOVA and Pearson correlation analysis were used.

Results: Altogether 589 patients were included. Median age was 56 years [21-86]. Patients were diagnosed between September 2005 and March 2017. Number of patients treated with OBC per unit ranged between 4 and 145. High volume units were doing a mean of 19.3 OBCs per year [17.3 – 26.5] vs. low volume units doing 11.1 OBCs per year [7 .7– 14.4] (p=0.012).

23 different oncoplastic surgical techniques were applied. Range of oncoplastic techniques used was associated with case-loads: high volume units used a wider range (8 – 14 different techniques) compared to low volume units (3 – 6) (p=0.004). Volume displacement was done in 515 patients (91.3%), volume replacement in 49 patients (8.7%). OBC was carried out as a joint operation between a breast and a plastic surgeon in 66.3% (389 patients). Immediate contralateral symmetrisation rate was significantly higher when the procedure was carried out as a joint operation (70.7% vs. not joint operations: 29.8%; p<0.001).

Incomplete excision rate was 10.4% (60 of 578). Incomplete excision was significantly higher after invasive lobular carcinoma (18.9%; 10 of 43; p=0.0292). After neoadjuvant chemotherapy incomplete excision rate was significantly lower (3%; 2 of 66 vs. no neoadjuvant chemotherapy: 11%; 35 of 319; p=0.031).

Neodjuvant systemic treatment rate was 28.6% (142 of 496 patients). Of those 68 patients received neoadjuvant chemotherapy (13.7%) and 74 patients had neoadjuvant hormonal treatment (14.9%). Neoadjuvant systemic treatment rate varied amongst the units from 9.7% to 57.2% for patients with invasive carcinoma.

259 patients diagnosed with (non)invasive carcinoma had a median follow-up time of 5 years [35-124]. Of these 7 patients (2.7%) developed isolated local recurrence. 5-year local recurrence rate after DCIS was higher than after pure invasive ductal carcinoma (DCIS: 8.3%; 3 of 36 vs. ductal: 1.6%; 3 of 181; p=0.02567). 5-year disease-free survival of these patients was 91.7%, overall survival was 93.8%, and cancer-specific survival was 96.1%.

145 of 510 patients developed complications, which is 28.4% overall complication rate. 71 patients had major complications (13.9%) and 74 patients had minor complications (14.5%). Overall complication rate was significantly lower after neoadjuvant chemotherapy (15.9%; 11 of 69) compared to patients who did not receive neoadjuvant chemotherapy (27.9%; 127 of 455 patients) (p=0.035).

Conclusion: this national audit demonstrated similar outcomes overall compared to relevant published data. Units should be urged to build stronger collaboration in order to reduce variability in OBC practices.

None of the authors have conflict of interest to declare.

Citation Format: Romics L, Macaskill J, Fernandez T, Morrow E, Simpson L, Pitsinis V, Barber M, Tovey S, Masannat Y, Young O, Mansell J, Stallard S, Doughty J, Dixon M. Oncoplastic breast conservations – The Scottish Audit: Surgical techniques, oncological outcomes, complication rates and variations in practice across the country based on the analysis of 589 patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-13-01.

Properties and characteristics of the dyes injected to assist axillary sentinel node localization in breast surgery

AIMS

A review of the safety profile of dyes injected to assist in sentinel lymph node biopsy (SLNB) in breast cancer.

METHODS

A literature search was performed of the medline database 1966-2005 using the Ovid web Gateway detailing the words sentinel node, breast cancer, allergic reactions, blue dye, isosulfan blue, patent blue and methylene blue.

RESULTS

There are reported side-effects from the parenteral administration of dyes, which range from minor to life threatening in severity. There are differences between the dyes as regards their effects. These aspects are discussed.

CONCLUSION

Many dyes have been used for SLNB with acceptable identification rates. There are variable side-effects for each of those dyes. Further research is needed to clarify the safety profile of these dyes.

Chronic contained rupture of abdominal aortic aneurysm presenting with longstanding back pain

Abdominal aortic aneurysm (AAA) is one of the important differential diagnoses of back pain which is often missed. Chronic contained rupture is a rare event that can cause diagnostic difficulties, presenting in different ways such as back pain, neuropathy or groin mass. We are presenting a case of 46-year-old man who presented with history of recurrent low back pain radiating to his left leg, associated with sensory deficit in the left thigh. His complaint proved to be resulting from chronic contained AAA leak.

Leiomyosarcoma of the inferior vena cava presenting as a left-sided variocele

Leiomyosarcomas of the great vessels are rare, but the most common site for them is the inferior vena cava. Due to non-specific clinical signs, diagnosis is usually late. At present, surgery is the treatment of choice. This is a case report of a 44-year-old man who presented with left groin discomfort and a left varicocele which were secondary to leiomyosarcoma of the inferior vena cava.