Wait times at Christchurch Hospital for adjuvant breast irradiation and the impact of the COVID-19 pandemic

Globally, breast cancer is the most common incident cancer in women, accounting for 8.9 million deaths and 213.2 million disease-adjusted life years.¹ In Aotearoa New Zealand, breast cancer is the third most common cancer and accounts for more than 650 deaths annually.² Delays in treatment are likely to result in poorer outcomes. A large meta-analysis published by Gupta et al. reported the relative risk of local recurrence per month of delay from surgical resection to commencing radiation treatment as 1.08 (95% confidence interval [CI] 1.02–1.14, p=0.015).³ Waiting times of 6 weeks or more from completion of chemotherapy to start of radiation treatment were associated with worse event-free survival, hazard ratio 1.50 (95% CI 1.00–2.22, p=0.047), in one Ontario-based study.⁴ A 2025 meta-analysis examining delays across surgery, chemotherapy and radiation therapy reported rising all-cause mortality with longer wait times: hazard ratios of 1.12 (95% CI 1.08–1.15) at 4 weeks, 1.25 (95% CI 1.17–1.33) at 8 weeks and 1.39 (95% CI 1.26–1.53) at 12 weeks.⁵ Delays in adjuvant radiation treatment for breast cancer are associated with worse oncological outcomes, including local recurrence, distant cancer metastasis and death.

New Zealand’s Optimal cancer care pathway for people with breast cancer, December 2024, outlines time frame standards for optimal treatment.⁶ Patients with high suspicion of breast cancer should have initial investigation within 2 weeks and referral to a breast surgeon within 2 weeks of diagnosis.⁶ First cancer treatment, surgery or neoadjuvant therapy should occur within 62 days of referral triage and within 4 weeks of decision to treat.⁶ Adjuvant chemotherapy should begin within 6 weeks of surgery.⁶ Adjuvant radiation should begin within 8 weeks of breast surgery completion or 3–4 weeks after completion of adjuvant chemotherapy.⁶

Service provision has been impacted across many areas of health because of the COVID-19 pandemic. In New Zealand, there were 104 fewer people diagnosed with cancer (all cancers) in the month of August 2021 compared to August 2018/2019, a 9% decrease.⁷ The Canterbury District Health Board reported no change in new cancer registrations for the month of August 2018/2019 and 2021, with a subsequent 18% increase in new cancer registration for the month of September.⁸ This change likely indicates a lag in services coinciding with a regional COVID-19 lockdown.

Aim

We aimed to quantify the wait times for patients receiving adjuvant radiation treatment at Christchurch Hospital and the trend of this over time. Additionally, we aimed to assess the impact of the COVID-19 pandemic with a focus on how the lockdown restrictions impacted the wait time trends.

Method

Ethics and informed consent

Individual patient informed consent was not obtained for this retrospective observational study. Ethics approval was granted by the ethics review committee for low-risk research within Canterbury District Health Board, Department of Oncology. Patient information datasets have been de-identified.

Patient selection

Patients with a diagnosis of “breast cancer” starting radiation treatment at Christchurch Hospital between 1 January 2018 and 31 December 2022 were identified using the Mosaiq database. The International Classification of Diseases 10th revision (ICD-10) codes used were C50 (malignant neoplasm of breast), C501 (malignant neoplasm of central portion of breast), C502 (malignant neoplasm of upper-inner quadrant of breast), C503 (malignant neoplasm of lower-inner quadrant of breast), C504 (malignant neoplasm of upper-outer quadrant of breast), C505 (malignant neoplasm of lower-outer quadrant of breast), C506 (malignant neoplasm of axillary tail of breast) and C509 (malignant neoplasm of breast of unspecified site).

Patient exclusion criteria

Patients who did not undergo a surgical procedure were excluded. Duplicate entries, such as patients receiving bilateral treatment, were processed as a single data point. Carcinoma in situ was excluded. Radiation treatment for breast cancer recurrence was excluded. Patients who underwent neoadjuvant chemotherapy were excluded due to having treatment prior to surgery, which made wait time assessment unreliable.

Data collection

In total, 978 patients were identified from 1 January 2018 and 31 December 2022. Of these, 296 patients were excluded using the above criteria. Data on these patients were collected retrospectively through electronic health records. The dates of last surgery, medical oncology referral, medical oncology first specialist appointment (FSA) and last administration of chemotherapy were manually input, as were the dates of radiation oncology referral, radiation oncology FSA (RO FSA) and radiation oncology computed tomography (CT) follow-up dates. The databases accessed for input were Health Connect South, Mosaiq and Éclair.

Data processing was completed using Microsoft Excel to formulate charts with trend lines and SPSS v29.0 to generate the regression gradients. Key dates used to account for regional and national COVID-19 lockdowns affecting Christchurch Hospital were as follows: initial nationwide lockdown (Alert Level 4) from 23 March 2020 until Level 1 nationwide on 9 June 2020; followed by subsequent Level 2 lockdown from 12 August 2020 until Level 1 on 22 September 2020.⁷ Three trend lines were generated to account for these dates, including: all quarters, all quarters excluding quarter 1 to quarter 2 2020, and all quarters excluding quarter 1 to quarter 3 2020.

Statistical methods

The wait times associated with the intervals from surgery or chemotherapy to radiation were summarised as medians within each quarter for the 6 years of surgical procedures. A linear regression analysis was then performed, weighted by the number of procedures included in each quarter, to generate the wait time gradients for each wait time component. The 95% CIs and p-values were generated for the linear wait time gradients. The number of additional local recurrences, excluding patients who received chemotherapy, was calculated using the median number of days from last surgery to the first fraction of radiation, with rates of local recurrence adjusted per month (30 days) of delay at a rate of 1.08 as outlined by the meta-analysis from Gupta et al.³

Results

Demographics

A total of 682 patients were included in the study. Two hundred and ninety-six patients were excluded for the following reasons: palliative intent treatment (173 patients), neoadjuvant chemotherapy (87 patients), bilateral treatment/duplicate entries (17 patients), carcinoma in situ (17 patients) and recurrence of cancer (two patients).

The baseline demographics and clinico-pathological characteristics are summarised in Table 1.

Treatment

External beam radiation treatment included varying fractionation regimes, including 26Gy in five fractions, 40.05Gy in 15 fractions and 50Gy in 25 fractions. A radiotherapy tumour bed boost was given in 7.3% of included patients.

Surgery was typically with wide local excision or mastectomy plus sentinel lymph node biopsy. If positive margins were identified, a further re-excision of margins surgery was offered. Completion axillary nodal dissection was offered for those with positive sentinel lymph nodes.

The standard adjuvant chemotherapy regimen used was four cycles of 3-weekly doxorubicin and cyclophosphamide followed by 12 cycles of weekly paclitaxel. Those with human epidermal growth factor receptor-type 2 receptor positivity were offered trastuzumab in addition to this.

Five years of adjuvant endocrine therapy was offered to those who were hormone receptor positive.

View Table 1–2, Figure 1–3.

Outcomes

The process from surgery to radiation can be broken down as demonstrated in Figure 1.

Each component was tabulated to generate a per annum change in wait times, using median number of days as demonstrated in Table 2. The median wait time to radiation treatment from last surgery was 72 days (interquartile range [IQR] 58–84 days), and from last chemotherapy was 36 days (IQR 31.5–50 days). The per annum increase in median wait times from date of last surgery to first fraction of radiation was 7.2 days (95% CI 6.84–7.65 days, p=<0.001), and from last chemotherapy was −0.3 days (95% CI −0.97–0.32 days, p=<0.326).

The median wait times in days from last surgery to the first fraction of radiation in those who had a medical oncology FSA but did not proceed to chemotherapy versus those who did not have a medical oncology FSA was 77 days (IQR 63.25–89 days) and 70 days (IQR 57–84 days) respectively.

Increases in wait times have been seen in each step of the process from surgery, to RO FSA, to CT planning session and to delivery of the first fraction of radiation for those not receiving adjuvant chemotherapy. The largest component of this wait time is from surgery to RO FSA, with a 4.4 days per annum increase. Intradepartmental delays have also been seen a 2.1 days per annum increase for RO FSA to CT planning and a 0.4 days per annum increase for CT planning to first fraction.

Gupta et al. included 13,921 patients in a meta-analysis for the effect of waiting times for post-operative radiotherapy in breast-conserving surgery and reported a relative risk of local recurrence per month of delay from surgical resection to commencing radiation treatment as 1.08 (95% CI 1.02–1.14, p=0.015).³ Local recurrence rates in Christchurch are 5.3% at 10 years.⁹ When applied to this cohort of patients, there were 5.5 predicted, additional local recurrences (25th to 75th centile range of 4.98–5.95) at 10 years for the 499 patients who underwent breast surgery followed by adjuvant radiation (excluding chemotherapy).

Figure 2 shows a general upwards trend in wait times for patients with breast cancer to receive their first fraction of adjuvant radiation treatment after surgery at Christchurch Hospital. An initial rise in quarter 1 of 2020 aligns with the nationwide COVID-19 Alert Level 4 lockdown. Wait times then decrease in quarters 2 and 3 of 2020, during smaller, regional Alert Level 2 lockdowns, possibly reflecting fewer surgeries in the preceding quarters. After these periods, wait times return to the prior upwards trajectory.

Table 2 and Figure 3 demonstrate a slight reduction in wait times for adjuvant radiation following chemotherapy. This cohort was small (183 patients) and lacked statistical significance (p=0.326), limiting firm conclusions.

In both Figure 2 and 3, the overall trend lines remain unchanged when including or excluding the COVID-19 lockdown quarters. The trendlines overlapped for all quarters, excluding quarter 1 to quarter 2 of 2020, and excluding quarter 1 to quarter 3 of 2020.

Figures 2 and 3 show the proportion of patients waiting longer than the target time frames (<56 days from surgery, <28 days from chemotherapy).⁶ There does not appear to be a clear pattern to this trend. In general, patients are waiting over the recommended time at Christchurch Hospital for adjuvant breast radiation treatment.

Discussion

Te Aho o Te Kahu – Cancer Control Agency released national guidance for radiation oncology services during COVID-19, outlining response plans based on disruption levels (none to significant) and service activity (levels 1–5, with level 5 representing lower-risk conditions that could be deferred). Patients with an estimated <20% 10-year recurrence risk, common among those with hormone receptor–positive early breast cancer on endocrine therapy, could be managed as level 5 conditions. During periods of moderate disruption, when hospital spaces were repurposed for COVID-19 care, level 5 patients could be considered for delayed radiation treatment. Christchurch Hospital did not need to convert its outpatient radiation oncology department into a COVID-19 facility, so these measures were not required. The guidance also recommended hypofractionated radiation regimens when clinically appropriate (in: personal communication from Te Aho o Te Kahu – Cancer Control Agency). In our cohort, 97.4% of patients received hypofractionated treatment.

The impact of the COVID-19 pandemic on wait times for patients receiving adjuvant breast cancer irradiation at Christchurch Hospital was limited to the period during and immediately after the national and regional lockdowns in the Canterbury Region between the first and third quarters of 2020. The initial peak in wait times during quarter 1 of 2020 could potentially be attributed to service planning precautions seen early in the COVID-19 pandemic as the New Zealand health system was preparing for the worst-case scenario of a widespread COVID-19 outbreak. The number of wide local excision procedures performed at Christchurch Hospital appeared to be reduced during this same period. This may explain the reduced wait times seen during quarter 2 and quarter 3 of 2020. As restrictions lifted in Canterbury, from quarter 4 of 2020 onwards we see a steady increase in wait times. Aside from the small chemotherapy cohort, which showed a slight reduction in wait times (–0.3 days per annum, 95% CI –0.97–0.32, p=<0.326), there was an overall increasing trend in wait times for adjuvant breast radiation at Christchurch Hospital. The overlapping trend lines, including and excluding the national (quarter 1 to quarter 2 of 2020) and regional (quarter 1 to quarter 3 of 2020) COVID-19 lockdown period, suggest the COVID-19 pandemic did not contribute significantly to the overall trend in increasing wait times for those receiving adjuvant breast cancer irradiation at Christchurch Hospital. The pandemic appeared to cause a peak and subsequent trough in wait times, limiting its overall impact.

The lack of increasing wait times in the small chemotherapy cohort is promising. However, a significant percentage of patients are still waiting over the target 28-day period, highlighting a potential area for improvement in timely referrals and reviews.

These findings may inform future public health strategies to minimise disruptions in oncology service delivery during potential pandemics.

Increasing wait times at each step could be explained by an increased demand for radiation treatment across many tumour streams. Within New Zealand there has been an increase in radiation treatment courses by 19% and number of fractions delivered by 13.7% from 2011 to 2019.¹⁰ Radiation therapist numbers have remained unchanged over the same period, resulting in a 20% increase in treatment course per radiation therapist.¹⁰ Increasing future staffing of radiation oncologists, radiation therapists, physicists and nursing and administration staff may improve the supply to meet the increased demand. Linear accelerator numbers in New Zealand have increased by four, from 28 to 32 during 2010 to 2019, with only one of these being within the public health sector.¹⁰ The majority, 62.5%, of linear accelerators were more than 8 years old.¹⁰ Improving infrastructure and linear accelerator capacity through longer operation times, new machines and additional planning CT machinery may relieve potential bottlenecks to service provision. Longer operating hours may work as a short-term solution but will likely come with the added risk of staff burnout and reduced staff retention in the longer term, so must be viewed with caution. This is particularly relevant given the greater workload of staff already seen between 2011 and 2019.

Regular multidisciplinary breast cancer meetings are crucial to ensure timely and accurate referrals. This can reduce unnecessary delays from decision to treat to treatment initiation. Accurately identifying those who need a medical oncology referral versus those who do not will potentially reduce wait times. There was an additional 7-day wait time for those who were referred to medical oncology but ultimately did not receive adjuvant chemotherapy. Most of these patients were likely appropriately referred to have an informed discussion regarding chemotherapy benefits and risks.

There was an estimation of 5.5 additional local recurrences at 10 years attributable to delays in our cohort. Treatment of local recurrence usually requires further surgery, commonly mastectomy with or without reconstruction, adding hospitalisation, surgical risk, recovery time, financial burden and significant psychological impact for patients and whānau. Mastectomy is associated with worse body image, psychological and sexual wellbeing outcomes compared with breast-conserving surgery.^11,12 Patients with recurrence incur an approximately 45% greater 10-year total treatment cost.¹³

Delays in breast cancer management (surgery, chemotherapy and radiation treatment) have shown worse all-cause mortality with each month of delay.⁵ Yung et al. showed worse breast cancer–specific mortality with delays of >8 weeks from surgery or chemotherapy to radiation, hazard ratio 1.49 (95% CI 1.01–2.22).¹⁴

It is paramount that we try to address and minimise delays to initiating radiation treatment for those with breast cancer.

Limitations

This was a retrospective analysis with a relatively small patient cohort, limiting its generalisability to other centres. There is likely to be a selection bias seen with the patients included due to the process of recruitment, particularly with quarter 2 to quarter 4 2017 patients. The selection criteria may have artificially excluded those who had completed their adjuvant radiation prior to 31 December 2017 and in doing so selected those with longer wait times.

Our study utilised findings from the meta-analysis by Gupta et al. (2016) to estimate the number of additional local recurrences at 10 years.³ This meta-analysis incorporated studies conducted between 1975 and 2015, encompassing patients treated with older radiotherapy techniques and fractionation schedules.³ Consequently, its applicability to our 2018–2022 cohort may be limited, potentially leading to an overestimation of the projected local recurrence rates in our population.

Conclusion

In summary, wait times for patients receiving adjuvant radiation treatment at Christchurch Hospital have been increasing. There appeared to be some impact from the COVID-19 pandemic, with more fluctuation in wait times during the lockdown periods impacting the Canterbury Region. Overall, the wait times did not appear to be permanently affected by the COVID-19 pandemic. There is an importance for timely and appropriate referrals to minimise future wait times, with an emphasis on the role of the multidisciplinary breast cancer meetings. Excessive delays in adjuvant radiation treatment for breast cancer can lead to additional local recurrences, which has a detrimental impact on patient and whānau wellbeing, additional cost to the public health sector and possible further pressures on the health infrastructure. Demand for radiation treatment services appears to be increasing and so measures must be taken both locally and nationally to address this through staffing, infrastructure and service provision means. Adhering to and monitoring the timeframes suggested in Optimal cancer care pathway for people with breast cancer will provide an objective measure for service provision and quality improvement to help guide future health investment targets.