Primary hyperparathyroidism in adults-(Part II) surgical management and postoperative follow-up: Position statement of the Endocrine Society of Australia, The Australian & New Zealand Endocrine Surgeons, and The Australian & New Zealand Bone and Mineral Society.

OBJECTIVE: To develop evidence-based recommendations to guide the surgical management and postoperative follow-up of adults with primary hyperparathyroidism. METHODS: Representatives from relevant Australian and New Zealand Societies used a systematic approach for adaptation of guidelines (ADAPTE) to derive an evidence-informed position statement addressing eight key questions. RESULTS: Diagnostic imaging does not determine suitability for surgery but can guide the planning of surgery in suitable candidates. First-line imaging includes ultrasound and either parathyroid 4DCT or scintigraphy, depending on local availability and expertise. Minimally invasive parathyroidectomy is appropriate in most patients with concordant imaging. Bilateral neck exploration should be considered in those with discordant/negative imaging findings, multi-gland disease and genetic/familial risk factors. Parathyroid surgery, especially re-operative surgery, has better outcomes in the hands of higher volume surgeons. Neuromonitoring is generally not required for initial surgery but should be considered for re-operative surgery. Following parathyroidectomy, calcium and parathyroid hormone levels should be re-checked in the first 24 h and repeated early if there are risk factors for hypocalcaemia. Eucalcaemia at 6 months is consistent with surgical cure; parathyroid hormone levels do not need to be re-checked in the absence of other clinical indications. Longer-term surveillance of skeletal health is recommended. CONCLUSIONS: This position statement provides up-to-date guidance on evidence-based best practice surgical and postoperative management of adults with primary hyperparathyroidism.

Primary hyperparathyroidism in adults-(Part I) assessment and medical management: Position statement of the endocrine society of Australia, the Australian & New Zealand endocrine surgeons, and the Australian & New Zealand bone and mineral society.

OBJECTIVE: To formulate clinical consensus recommendations on the presentation, assessment, and management of primary hyperparathyroidism (PHPT) in adults. METHODS: Representatives from relevant Australian and New Zealand Societies used a systematic approach for adaptation of guidelines (ADAPTE) to derive an evidence-informed position statement addressing nine key questions. RESULTS: PHPT is a biochemical diagnosis. Serum calcium should be measured in patients with suggestive symptoms, reduced bone mineral density or minimal trauma fractures, and in those with renal stones. Other indications are detailed in the manuscript. In patients with hypercalcaemia, intact parathyroid hormone, 25-hydroxy vitamin D, phosphate, and renal function should be measured. In established PHPT, assessment of bone mineral density, vertebral fractures, urinary tract calculi/nephrocalcinosis and quantification of urinary calcium excretion is warranted. Parathyroidectomy is the only definitive treatment and is warranted for all symptomatic patients and should be considered for asymptomatic patients without contraindications to surgery and with >10 years life expectancy. In patients who do not undergo surgery, we recommend annual evaluation for disease progression. Where the diagnosis is not clear or the risk-benefit ratio is not obvious, multidisciplinary discussion and formulation of a consensus management plan is appropriate. Genetic testing for familial hyperparathyroidism is recommended in selected patients. CONCLUSIONS: These clinical consensus recommendations were developed to provide clinicians with contemporary guidance on the assessment and management of PHPT in adults. It is anticipated that improved health outcomes for individuals and the population will be achieved at a decreased cost to the community.

Bi-national Review of Phaeochromocytoma Care: Is ICU Admission Always Necessary?

BACKGROUND: Post-operative management after phaeochromocytoma resection includes monitoring of blood pressure and blood sugar, and vigilance for haemorrhage. Guidelines recommend 24 h of continuous blood pressure monitoring, usually necessitating HDU/ICU admission. We hypothesised that most patients undergoing phaeochromocytoma resection do not require post-operative HDU/ICU admission. We aim to describe current Australian and New Zealand perioperative management of phaeochromocytoma and determine whether it is safe to omit HDU/ICU care for most patients. METHODS: We collected retrospective data on patients undergoing excision of phaeochromocytoma in 12 centres around Australia and New Zealand between 2007 and 2019. Data collected included preoperative medical management, anaesthetic management, vasopressor support, HDU/ICU admission and complications. RESULTS: A total of 223 patients were included in the study, 173 (77%) of whom were admitted to HDU/ICU post-operatively. The group of patients treated in ICU was similar to the group of patients treated on the ward in terms of demographic and tumour characteristics, and there were significant differences in the proportion of patients admitted to HDU/ICU between centres. Of patients admitted to ICU, 71 (41%) received vasopressor support. This was weaned within 24 h in 55 (77%) patients. Patients with larger tumours (> 6 cm) and a transfusion requirement are more likely to require prolonged inotropic support. Among patients admitted to the ward, there were no complications that required escalation of care. CONCLUSIONS: Although not widespread practice in Australia and New Zealand, it appears safe for the majority of patients undergoing minimally invasive resection of phaeochromocytoma to be admitted to the ward post-operatively.

The impact of public performance reporting on cancer elective surgery waiting times: a data linkage study.

BACKGROUND: Excessive waiting times for cancer elective surgery are a concern in publicly funded healthcare systems. Several countries including Australia have introduced healthcare reforms involving time-based targets and public performance reporting (PPR) of hospital data. However, there is mixed evidence of their benefits. We sought to examine the impact of targets and PPR of cancer elective surgery waiting times on access to breast, bowel and lung cancer elective surgery. METHODS: We analysed routinely-collected linked data on admissions and waiting times for patients aged 15 years or over (n = 199,885) who underwent cancer surgery in a public hospital in Victoria, Australia over a 10-year period. We conducted difference-in-differences analyses to compare waiting times before (2006-07 to 2011-12) and after (2012-13 to 2015-16) the introduction of PPR in meeting these targets. RESULTS: Across all cancer types, urgent patients were all treated within 30 days before and after PPR. Following PPR, there was a slight increase in the mean waiting times across all cancer types and urgency categories. Patients with lung cancer waited on average two and half days longer for treatment and patients with breast cancer waited on average half-a-day less. There was no effect of PPR on waiting times for patients with bowel cancer across urgency categories. CONCLUSIONS: Our findings suggest that time-based targets and PPR had minimal impact on surgical waiting times. This may be due to reasonable waiting times prior to PPR, improved efficiency being masked by 20% growth in the population, lack of public knowledge that waiting times are publicly reported, or lack of real-time reporting to drive behavioural change. The use of generic elective surgery recommended waiting time measures for cancer is discussed.

Practice Patterns in Parathyroid Surgery: A Survey of Asia-Pacific Parathyroid Surgeons.

BACKGROUND: Practice variations exist amongst parathyroid surgeons depending on their expertise and resources. Our study aims to elucidate the choice of surgical techniques and adjuncts used in parathyroid surgery by surgeons in the Asia-Pacific region. METHODS: A 25-question online survey was sent to members of five endocrine surgery associations. Questions covered training background, practice environment and preferred techniques in parathyroid surgery. Respondents were divided into three regions: Australia/New Zealand, South/South East Asia and East Asia, and responses were analysed according to region, specialty, case volume and years in practice. RESULTS: One hundred ninety-six surgeons returned the questionnaire. Most surgeons (98%) routinely perform preoperative imaging, with 75% preferring dual imaging with 99mTcsestamibi and ultrasound. Ten per cent of surgeons use parathyroid 4DCT as first-line imaging, more commonly in East Asia (p = 0.038). Minimally invasive parathyroidectomy is the favoured technique of choice (97%). Most surgeons reporting robotic or endoscopic approaches are from East Asia. Rapid intraoperative parathyroid hormone is accessible to just under half of the surgeons but less available in Australian/New Zealand (p < 0.001). The use of intraoperative neuromonitoring is not commonly used, even less so amongst Asian surgeons (p = 0.048) and surgeons with low case load (p = 0.013). CONCLUSION: Dual localisation techniques are the preferred choice of investigations in preparation for parathyroid surgery, with minimally invasive surgery without neuromonitoring the preferred approach. Use of adjuncts is sporadic and limited to certain centres.

Four-Dimensional Computed Tomography: Clinical Impact for Patients with Primary Hyperparathyroidism.

BACKGROUND: In recent years, four-dimensional computed tomography (4DCT) has emerged as a new localization study for primary hyperparathyroidism (pHPT). OBJECTIVE: We aimed to assess the added value of 4DCT in our institution in the first 4 years of use. METHODS: A retrospective cohort study was conducted from February 2004 to June 2015. Since 2011, patients over 50 years of age without concordant sestamibi-SPECT (SeS) and ultrasound (US) findings underwent 4DCT. Imaging results, surgical findings, histopathology, and postoperative biochemistry were collected. RESULTS: A total of 536 parathyroid operations in 510 patients were performed during the study period. The overall cure rate was 99.2% after reoperation in some patients, and the overall sensitivity for SeS was 76.0%, and 74.8% for US. Since 2011, 100 patients without concordant SeS/US findings have undergone 4DCT, with a sensitivity of 72.9%. This is in comparison to the sensitivities for SeS (48.3%) and US (52.3%). 4DCT was more sensitive in patients with persistent/recurrent disease (60.0% compared with SeS 43.8% and US 36.4%) and patients with multigland disease (67.4% compared with SeS 40.9% and US 42.1%). Comparison between outcomes in the pre- versus post-CT era demonstrated no difference in the initial cure rate (95.4 vs. 95.9%, p = 0.85) or the rate of minimally invasive parathyroidectomies (74.5 vs. 79.9%, p = 0.22). CONCLUSION: Parathyroid 4DCT can aid surgical planning in cases without concordant SeS/US findings; however, the introduction of 4DCT as a second-line test did not change our overall cure rate or rate of minimally invasive parathyroidectomy. The role of 4DCT as the primary localization study for pHPT merits further investigation.

Dynamic CT for Parathyroid Adenoma Detection: How Does Radiation Dose Compare With Nuclear Medicine?

OBJECTIVE: Dynamic CT is increasingly used for preoperative localization of parathyroid adenomas, but concerns remain about the radiation effective dose of CT compared with that of 99mTc-sestamibi scintigraphy. The purpose of this study was to compare the radiation dose delivered by three-phase dynamic CT with that delivered by 99mTc-sestamibi SPECT/CT performed in accordance with our current protocols and to assess the possible reduction in effective dose achieved by decreasing the scan length (i.e., z-axis) of two phases of the dynamic CT protocol. MATERIALS AND METHODS: The effective dose of a 99mTc-sestamibi nuclear medicine parathyroid study performed with and without coregistration CT was calculated and compared with the effective dose of our current three-phase dynamic CT protocol as well as a proposed protocol involving CT with reduced scan length. RESULTS: The median effective dose for a 99mTc-sestamibi nuclear medicine study was 5.6 mSv. This increased to 12.4 mSv with the addition of coregistration CT, which is higher than the median effective dose of 9.3 mSv associated with the dynamic CT protocol. Reducing the scan length of two phases in the dynamic CT protocol could reduce the median effective dose to 6.1 mSv, which would be similar to that of the dose from the 99mTc-sestamibi study alone. CONCLUSION: Dynamic CT used for the detection of parathyroid adenoma can deliver a lower radiation dose than 99mTc-sestamibi SPECT/CT. It may be possible to reduce the dose further by decreasing the scan length of two of the phases, although whether this has an impact on accuracy of the localization needs further investigation.

Cousins not twins: intratumoural and intertumoural heterogeneity in syndromic neuroendocrine tumours.

Hereditary endocrine neoplasias, including phaeochromocytoma/paraganglioma and medullary thyroid cancer, are caused by autosomal dominant mutations in several familial cancer genes. A common feature of these diseases is the presentation of multiple primary tumours, or multifocal disease representing independent tumour clones that have arisen from the same initiating genetic lesion, but have undergone independent clonal evolution. Such tumours provide an opportunity to discover common cooperative changes required for tumourigenesis, while controlling for the genetic background of the individual. We performed genomic analysis of synchronous and metachronous tumours from five patients bearing germline mutations in the genes SDHB, RET, and MAX. Using whole exome sequencing and high-density single-nucleotide polymorphism arrays, we analysed two to four primary tumours from each patient. We also applied multi-region sampling, to assess intratumoural heterogeneity and clonal evolution, in two cases involving paraganglioma and medullary thyroid cancer, respectively. Heterogeneous patterns of genomic change existed between synchronous or metachronous tumours, with evidence of branching evolution. We observed striking examples of evolutionary convergence involving the same rare somatic copy-number events in synchronous primary phaeochromocytoma/paraganglioma. Convergent events also occurred during clonal evolution of metastatic medullary thyroid cancer. These observations suggest that genetic or epigenetic changes acquired early within precursor cells, or pre-existing within the genetic background of the individual, create contingencies that determine the evolutionary trajectory of the tumour. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The impact of delayed diagnosis and treatment due to COVID-19 on Australian thyroid cancer patients: a qualitative interview study.

OBJECTIVES: The study aims to investigate the perceptions of patients with thyroid cancer on the potential impact of diagnosis and treatment delays during the COVID-19 pandemic. DESIGN: This study involved qualitative semi-structured telephone interviews. The interviews were transcribed verbatim, analysed using the thematic framework analysis method and reported using the Consolidated Criteria for Reporting Qualitative Research. SETTING: Participants in the study were treated and/or managed at hospital sites across New South Wales and Victoria, Australia. PARTICIPANTS: 17 patients with thyroid cancer were interviewed and included in the analysis (14 females and 3 males). RESULTS: The delays experienced by patients ranged from <3 months to >12 months. The patients reported about delays to diagnostic tests, delays to surgery and radioactive iodine treatment, perceived disease progression and, for some, the financial burden of choosing to go through private treatment to minimise the delay. Most patients also reported not wanting to experience delays any longer than they did, due to unease and anxiety. CONCLUSIONS: This study highlights an increased psychological burden in patients with thyroid cancer who experienced delayed diagnosis and/or treatment during COVID-19. The impacts experienced by patients during this time may be similar in the case of other unexpected delays and highlight the need for regular clinical review during delays to diagnosis or treatment.

The role of seabird guano in maintaining North Atlantic summertime productivity.

Nutrients supplied via seabird guano increase primary production in some coastal ecosystems. A similar process may occur in the open ocean. To investigate this directly, we first measured bulk and leachable nutrient concentrations in guano sampled in the North Atlantic. We found that guano was strongly enriched in phosphorus, which was released as phosphate in solution. Nitrogen release was dominated by reduced forms (ammonium and urea) whilst release of nitrate was relatively low. A range of trace elements, including the micronutrient iron, were released. Using in-situ bioassays, we then showed that supply of fresh guano to ambient seawater increases phytoplankton biomass and photochemical efficiencies. Based on these results, modelled seabird distributions, and known defecation rates, we estimate that on annual scales guano is a minor source of nutrients for the surface North Atlantic. However, on shorter timescales in late spring/summer it could be much more important: Estimates of upper-level depositions of phosphorus by seabirds were three orders of magnitude higher than modelled aerosol deposition and comparable to diffusion from deeper waters.

Surgical Management of Indeterminate Thyroid Nodules across Different World Regions: Results from a Retrospective Multicentric (the MAIN-NODE) Study.

Indeterminate thyroid nodules (ITNs) are characterized by an expected malignancy ranging from 5% to 30%, with most patients undergoing a diagnostic, rather than therapeutic, operation. The aim of our study was to compare the approach to ITNs across different regions of the world. In this retrospective, multicentric, international study, according to the WHO classification, we identified the South East Asian Region (SEAR), the Americas Region (AMR), the Eastern Mediterranean Region (EMR), the Europe Region (EUR), and the Western Pacific Region (WPR). One high-volume thyroid centre was included for each region. Demographic, preoperative, and pathologic data were compared among the different regions. Overall, 5737 patients from five high-volume thyroid centres were included in this study. We found that the proportion of ITNs over the global activity for thyroid disease was higher in the EUR (37.6%) than in the other regions (21.1-23.6%). In the EMR, the patients were significantly younger (with a mean of 43.1 years) than in the other regions (range, 48.8-57.4 years). The proportion of lobectomy was significantly higher in the WPR, where 83.2% (114/137) of patients received this treatment, than in the other regions, where lobectomies were performed in 44.1-58.1% of patients. The pathological diagnosis of malignancy was significantly higher in the SEAR centre, being over 60%, than in centres of the other regions, where it ranged from 26.3% to 41.3%. The occurrence of lymph node metastases was higher in the WPR (27.8%), AMR (26.9%), and EMR (20%) centres than in the EUR and SEAR centres, where it was lower than 10%. In summary, we found in our study different approaches and outcomes in the diagnosis and treatment of ITNs among countries. Overall, almost 60% of patients with ITNs who underwent surgery actually presented a benign disease, potentially undergoing an unnecessary operation.

2021 Asia-Pacific Graves' Disease Consortium Survey of Clinical Practice Patterns in the Management of Graves' Disease.

AIM: Although Graves' disease (GD) is common in endocrine practices worldwide, global differences in diagnosis and management remain. We sought to assess the current practices for GD in countries across Asia and the Pacific (APAC), and to compare these with previously published surveys from North America and Europe. METHODS: A web-based survey on GD management was conducted on practicing clinicians. Responses from 542 clinicians were received and subsequently analysed and compared to outcomes from similar surveys from other regions. RESULTS: A total of 542 respondents participated in the survey, 515 (95%) of whom completed all sections. Of these, 86% were medical specialists, 11% surgeons, and 3% nuclear medicine physicians. In addition to serum thyroid-stimulating hormone (TSH) and free thyroxine assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (68%) during initial work-up. Thyroid ultrasound is requested by about half of respondents (53%), while the use of nuclear medicine scans is limited. The preferred first-line treatment is anti-thyroid drug (ATD) therapy (79%) with methimazole (MMI) or carbimazole (CBZ), followed by radioiodine (RAI; 19%) and surgery (2%). In case of surgery, one-third of respondents would opt for a subtotal rather than a total thyroidectomy. In case of mild Graves orbitopathy (GO), ATDs (67%) remains the preferred treatment, but a larger proportion of clinicians prefer surgery (20%). For a patient with intention to conceive, the preferred treatment pattern remained unchanged, although propylthiouracil (PTU) became the preferred ATD-agent during the first trimester. In comparison to European and American practices, marked differences were noted in the relatively infrequent usage of nuclear medicine scans and the overall higher use of a ATDs and ß-blockers and adjunctive ATD-treatment during RAI in the APAC-group. CONCLUSION: Although regional differences regarding the diagnosis and management of GD are apparent in this first pan-Asia-Pacific survey, this study reveals the overall approach to the management of this disease in Asia-Pacific generally tends to fall between the trends appreciated in the American and European cohorts.

Endocrine surgeon-performed US guided thyroid FNAC is accurate and efficient.

BACKGROUND: Ultrasound guided fine needle aspiration cytology (US-FNAC) is a key diagnostic technique used to assess thyroid nodules. This procedure has been the domain of radiologists, but it is increasingly performed by endocrine surgeons. In the present study we aimed to assess the accuracy and clinical efficiency of US-FNAC performed by endocrine surgeons. PATIENTS AND METHODS: This study was a retrospective review of consecutive patients in a 3-year period who underwent US-FNAC performed by endocrine surgeons and radiologists. Medical records, cytology results, and surgical pathology results were collected and analyzed. RESULTS: A total of 576 US-FNAC were performed on 402 patients during the study period. The endocrine surgeons and radiologists performed 299 and 277 US-FNAC, respectively. The FNAC inadequacy rate was 5.3 % for the endocrine surgeons and 9.3 % for the radiologists (p = 0.05). For thyroid cancer, the sensitivity, specificity, and false negatives of the US-FNAC for the endocrine surgeons was 87 %, 98 %, and 3 %, respectively while that for the radiologists was 88 %, 95 %, and 3.5 %, respectively. Patients with thyroid cancer had a shorter time to surgery in the endocrine surgeons' group (mean 15.3 days) compared to the radiologists' group (mean: 53.3 days; p = 0.01). CONCLUSIONS: US-FNAC performed by an experienced endocrine surgeon is accurate and allows efficient surgical management for patients with thyroid cancer.

Single-nuclei and bulk-tissue gene-expression analysis of pheochromocytoma and paraganglioma links disease subtypes with tumor microenvironment.

Pheochromocytomas (PC) and paragangliomas (PG) are rare neuroendocrine tumors associated with autonomic nerves. Here we use single-nuclei RNA-seq and bulk-tissue gene-expression data to characterize the cellular composition of PCPG and normal adrenal tissues, refine tumor gene-expression subtypes and make clinical and genotypic associations. We confirm seven PCPG gene-expression subtypes with significant genotype and clinical associations. Tumors with mutations in VHL, SDH-encoding genes (SDHx) or MAML3-fusions are characterized by hypoxia-inducible factor signaling and neoangiogenesis. PCPG have few infiltrating lymphocytes but abundant macrophages. While neoplastic cells transcriptionally resemble mature chromaffin cells, early chromaffin and neuroblast markers are also features of some PCPG subtypes. The gene-expression profile of metastatic SDHx-related PCPG indicates these tumors have elevated cellular proliferation and a lower number of non-neoplastic Schwann-cell-like cells, while GPR139 is a potential theranostic target. Our findings therefore clarify the diverse transcriptional programs and cellular composition of PCPG and identify biomarkers of potential clinical significance.

Do routinely repeated computed tomography scans in traumatic brain injury influence management? A prospective observational study in a level 1 trauma center.

OBJECTIVE: To prospectively examine the clinical role of routine repeat computed tomographic scans of the brain (CTB) in patients with traumatic head injury. SUMMARY BACKGROUND DATA: The use of routine serial CTB after traumatic head injury is recommended by some authors, but remains controversial. METHODS: From March 2007 to October 2008, all patients with traumatic head injury admitted to the Royal Melbourne Hospital, a metropolitan, Level I trauma center, were prospectively studied. After the initial computed tomography brain scans, any subsequent CTBs were assessed and were recorded as being either "clinically indicated" or "routine" and ensuing medical and surgical management. Inpatient information was recorded and comparisons made according to indication for CTB, Glasgow Coma Scale, and management changes. RESULTS: A total of 651 patients were admitted with traumatic head injury over the 20-month study period. Of those, 39 underwent immediate craniotomy/craniectomy and were excluded from analysis. Another 25 were excluded due to incomplete data, leaving 591 patients for analysis. Of the 591 assessed, 401 were discharged with no further computed tomography investigation. One hundred and ninety patients underwent a total of 305 repeat brain scans, of which 149 were clinically indicated, whereas 156 were obtained as a "routine" investigation with no deterioration in patients' neurological status. Of the repeated scans, 71 were improved, 169 were unchanged, and 64 were worse. None of the 156 patients who received a "routine" CTB required a change in management. The 149 CTB performed for clinical deterioration resulted in a change in management in 28 patients (19%). The patients who underwent "indicated" computed tomographic scans and subsequently required a change in management were on average younger (P < 0.001) and more severely head injured (P = 0.001) than the patients not requiring a change in management. CONCLUSIONS: No patients from our cohort with a "routine" repeat CTB required a change in management. Given the costs and potential risks of routine repeat CTB, and lack of demonstrable benefit, the practice should be reconsidered. Repeat CTB is clearly indicated in patients with deteriorating neurological status, especially younger and more severely head-injured patients.

Outcomes of screening-detected ductal carcinoma in situ treated with wide excision alone.

BACKGROUND: Ductal carcinoma in situ (DCIS) is commonly identified on screening mammography. Standard treatment for localized DCIS is wide local excision (WLE) and adjuvant radiotherapy. This approach represents overtreatment in many cases, where the DCIS would never have become clinically significant, or where less intensive treatment would have been satisfactory. We reviewed the medium-term outcome of a cohort of screen detected DCIS patients treated mainly with WLE without radiotherapy. METHODS: All patients diagnosed with DCIS at NorthWestern BreastScreen between January 1994 and December 2005 were identified from a prospective database. Demographic, pathological, treatment, and outcome data were collected and analyzed. Survival and local recurrence (LR) rates were determined, and associations between various factors and recurrence were analyzed. RESULTS: A total of 422 patients were diagnosed with DCIS. There were 400 patients treated with WLE, and 27 of these received adjuvant radiotherapy. The 5- and 8-year overall and breast cancer specific survival rates were 96.1 and 91.3%, and 99.6 and 99.3%, respectively. The local recurrence rate was 15.4 and 17.1% at 5 and 8 years. Of 56 local recurrences, 34 had WLE after recurrence, 16 of which had adjuvant radiotherapy. No single factor was statistically significantly associated with local recurrence, although combining factors revealed groups where the LR rate was less than 5%. CONCLUSIONS: Breast cancer specific mortality was very low in this cohort of older patients with screen-detected DCIS. There was a moderate rate of local recurrence that could usually be salvaged with breast conservation. Decisions regarding adjuvant radiotherapy should take these findings into account.