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Serial measurements of hormone concentrations along baleen plates allow for reconstructions of mysticete whale reproductive histories. We assessed gestation and calving interval in bowhead whales (Balaena mysticetus) by measuring progesterone, oestradiol, corticosterone and nitrogen stable isotope ratios (δ15N) along baleen of 10 females from the eastern Canada-west Greenland population. Three immature females (body size < 14.32 m) had uniformly low progesterone concentrations across their baleen, while seven mature females (body size ≥ 14.35 m) had repeated, sustained elevations of progesterone indicative of pregnancies. The mean duration of progesterone elevations (23.6 ± 1.50 months) was considerably longer than the approximately 14 month gestation previously estimated for this species. We consider several possible explanations for this observation, including delayed implantation or sequential ovulations prior to gestation, strategies that would allow females to maximize their fitness in variable Arctic conditions, as well as suggest modified criteria defining gestation as a shorter component of the entire progesterone peak. Calving intervals varied within and among individuals (mean = 3.7 years; range = range 2.8-5.7 years), providing population-specific reproductive estimates for growth models used in bowhead whale management and conservation.

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These guidelines, informed by the best available evidence and consensus expert opinion, provide a framework to guide the timely initiation of chemotherapy for treating cancer. They sit at the intersection of patient experience, state-of-the-art disease management and rational efficient service provision for these patients at a system level. Internationally, cancer waiting times are routinely measured and publicly reported. In Australia, there are existing policies and guidelines relating to the timeliness of cancer care for surgery and radiation therapy; however, until now, equivalent guidance for chemotherapy was lacking. Timeliness of care should be informed, where available, by evidence for improved patient outcomes. Independent of this, it should be recognised that shorter waiting periods are likely to reduce patient anxiety. While these guidelines were developed as part of a proposed framework for consideration by the Victorian Department of Health, they are clinically relevant to national and international cancer services. They are intended to be used by clinical and administrative staff within cancer services. Adoption of these guidelines, which are for the timely triage, review and treatment of cancer patients receiving systemic chemotherapy, aims to ensure that patients receive care within a timeframe that will maximise health outcomes, and that access to care is consistent and equitable across cancer services. Local monitoring of performance against this guideline will enable cancer service providers to manage proactively future service demand.

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BACKGROUND: Chemotherapy plus radiotherapy is the standard of care for patients with limited stage Hodgkin lymphoma (HL). Radiotherapy is evolving from involved field radiotherapy (IFRT) to involved node radiotherapy (INRT) to decrease radiotherapy-related morbidity. In the absence of long-term toxicity data, dose-volume metrics of organs at risk (OAR) provide a surrogate measure of toxicity risk. PATIENTS AND METHODS: Ten female patients with stage I-IIA supradiaphragmatic HL were randomly selected. All patients had pre-chemotherapy computerised tomography (CT) and CT-positron emission tomography staging. Using CT planning, three radiotherapy plans were produced per patient: (i) IFRT, (ii) INRT using parallel-opposed beams and (iii) INRT using volumetric modulated arc therapy (VMAT). Radiotherapy dose was 30.6 Gy in 1.8 Gy fractions. OAR evaluated were lungs, breasts, thyroid, heart and coronary arteries. RESULTS: Compared with IFRT, INRT significantly reduced mean doses to lungs (P < 0.01), breasts (P < 0.01), thyroid (P < 0.01) and heart (P < 0.01), on Wilcoxon testing. Compared with conventional INRT, VMAT improved dose conformality but increased low-dose radiation exposure to lungs and breasts. VMAT reduced the heart volume receiving 30 Gy (V30) by 85%. CONCLUSIONS: Reduction from IFRT to INRT decreased the volumes of lungs, breasts and thyroid receiving high-dose radiation, suggesting the potential to reduce long-term second malignancy risks. VMAT may be useful for patients with pre-existing heart disease by minimising further cardiac toxicity risks.

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AIMS: Parotid-sparing radiotherapy (PSRT) was introduced for patients with selected head and neck cancer requiring bilateral upper-neck irradiation at our centre in 2000. The aim of this study was to compare the subjective degree of xerostomia in patients treated with PSRT between January 2000 and June 2003 with patients treated using conventional techniques (radiotherapy) over the same period. MATERIALS AND METHODS: Eligible patients were required to have completed treatment 6 months previously and be recurrence-free at the time of interview. PSRT was defined as conformal radiotherapy, in which the mean dose to at least one parotid gland was 33 Gy or less, as determined by the dose-volume histogram. Patients receiving radiotherapy were treated with standard parallel-opposed fields, such that both parotids received a minimum of 40 Gy. Xerostomia was assessed using a validated questionnaire containing six questions with a rating between 0 and 10. Lower scores indicated less difficulty with xerostomia. RESULTS: Thirty-eight eligible patients treated with PSRT were identified: 25 with oropharyngeal cancer and 13 with nasopharyngeal cancer (NPC). The mean overall questionnaire score (Q1-5) for this group was 4.20 (standard error = 0.33). Forty-four patients (24 oropharyngeal, 21 NPC) treated with radiotherapy over the same period were eligible. The mean overall questionnaire score (Q1-5) for this group was 5.86 (standard error = 0.35). The difference in mean overall scores between the two groups of patients was statistically significant (P < 0.001), as were the scores for four of the six individual questions. CONCLUSION: These results suggest that PSRT offers improved long-term xerostomia-related quality of life compared with conventional radiotherapy.

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Quality assurance ensures that planned treatments eventuate. Programmes must include feedback loops to promptly correct any shortfall in predetermined standards. In March 1999, a weekly Chart Round was introduced to verify that certain items relevant to quality care were being completed for patients of the Head and Neck Radiotherapy Unit at the Peter MacCallum Cancer Institute. The experience was reviewed after 1 year and it was found that the initiation of Chart Rounds has assisted in raising the level of item completion from 80% to 99% in similar groups of patients treated before and after the initiation of the Chart Round. Initiation of the Chart Round has also provided a useful forum for in-house peer-review, education and effective real-time communication between medical and allied health personnel, all of which has further added to the quality of patient care.

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