The impact of COVID-19 on colorectal cancer in regional Northern Australia and changes to treatment related to distance to care: a retrospective cohort study

Abstract

Background:

The COVID-19 pandemic has created challenges in the diagnosis and management of colorectal cancer (CRC). It was proposed in regional Northern Australia that the distance to services could further impact cancer outcomes, leading to delayed diagnosis. The authors compared the outcomes of patients prior and during the pandemic; with a focus on whether patients were presenting in the emergency setting with more advanced disease. The distance to treatment was also analysed to see if there was any impact to the management of patients with colorectal cancer.

Methods:

A retrospective analysis of 444 patients who underwent treatment for colorectal cancer over two time periods was examined. Time period 1 (prior to COVID-19); March 2017–July 2019 and time period 2 (during COVID-19); March 2020–July 2022. Only patients with colorectal adenocarcinoma were included if they were primarily treated at a hospital in northern Australia; those with benign pathologies or recurrent disease were also excluded. Data was collected in terms of treatment and outcomes and compared between the two groups. A separate analysis of whether locality affected outcomes and referral times was also performed.

Results:

In the time period prior to COVID-19, 174 patients’ required invasive management, while in the second time period during COVID-19, there were 188 patients managed surgically or endoscopically. Of the patients managed prior to COVID-19 17/174 (9.8%) patients required emergency interventions, during COVID-19 this number increased to 37/188 (19.7%). This difference was deemed to be statistically significant (P =0.008). No substantial difference in cancer staging at presentation was found between the two groups. There was an increase in complication rate found during COVID-19 34.6 vs 25.5% prior to COVID-19 (P=0.046). During COVID-19, the median time between General Practitioner (primary care physician) referral and colonoscopy was actually lower than prior to covid 26.5 vs 36 days (P=0.047). When comparing local to distant patients, we found locally based patients had lower rates of neoadjuvant treatment 18.9 vs 30.4% (P=0.018) and higher rates of open surgery 39.1 vs 26.5%, P =0.012. An increase in time between colonoscopy and outpatient department review (OPD) was seen in patients not from the local area 13 vs 18 days (P =0.006).

Conclusion:

The authors found during the COVID-19 pandemic a greater proportion of patients were presenting with colorectal cancer that required emergency intervention. This may be due to decreased presentations to general practitioners due to lockdown causing potential delays in diagnosis. The authors did not see more advanced disease in these patients presenting emergently, between the two groups. Further assessment of local patients’ vs patients from distant sites, showed difference in how patients were managed but similar outcomes. Our large catchment area with distance to treatment in Northern Australia may further impact the management of colorectal cancer in the future.

Introduction

Highlights

• Colorectal cancer has been shown to be associated with high rate of emergency presentations during the COVID-19 pandemic.

• Strategies to avoid delays in diagnosis and management are important.

• Regional areas seem to face similar issues.

• Distance to care can affect treatment profiles in colorectal cancer.

COVID-19 has impacted the delivery of healthcare across Australia, with the cancellation of elective procedures, to combat the high number of admissions with COVID-19 infections. A number of centres’ across the world have found that delayed endoscopic examination have led to more advanced colorectal cancer. They also found a higher incidence of emergency presentations secondary to more advanced disease^1–3. Chen et al.¹ has recently shown in Victoria that this trend has been replicated in Metropolitan centres in Australia.

In regional Queensland (northern Australia), we wanted to see if the distance to healthcare and strain on the local networks in providing elective endoscopy, would negatively affect work-up and treatment of colorectal cancer. In our Hospital Health Service, there is one dedicated tertiary facility providing subspecialist colorectal surgical services. To the south (around 350 km away), a large health district also refers rectal cancer patients for definitive surgical management with us. Our health service encompasses a number of rural hospitals, extending as far west as 500 km away; and ~150 km north and south. This district is home to ~250 000 people, with our institution providing tertiary services in the north of Queensland to nearly 700 000 people. Another remote north western health service district also drains directly to this Hospital Health Service with some centres’ being more than 1000 km away. In India, rural centres have found that reduced surgical capabilities during COVID-19 lockdowns lead to decreased number of cancer operations being performed⁴. This could be due to the fact that hospitals in certain areas at the peak of lockdown had elective surgery cancellations due to bed numbers^5,6.

The COVID-19 pandemic lead to the shutdown of many elective services in the early part of 2020. Across the world many guidelines were draughted including in the USA and UK to design systems that could help prepare for the influx of COVID-19 patients in hospital^5,6. In March 2020, the state of Queensland in Australia followed national advice at the time to only perform urgent category 1 (<30 days) procedures and some urgent category 2 procedures, affecting both surgical and endoscopic procedures⁷. This meant the triage of procedures was particularly important to ensure patients were not delayed in receiving care/work-up. At different times during the lockdown hospital services were limited in capabilities to perform some elective procedures. The number of COVID-19 infections and so-called waves impacted this, as did advice from the Chief Health Officer and national cabinet.

The use of neoadjuvant and adjuvant therapy in colon and rectal cancers, as well as the logistics of delivery, need to be considered in the middle of a pandemic. Colorectal practice with regards to the choice of approach, i.e., laparoscopic vs. open surgery, as well as the need for stoma formation, is also important. In the NHS, Morris et al.⁸ showed a higher rate of short-course radiotherapy in the management of rectal cancers. Other studies also showed this, as well as increased use of open surgery and some reduction in adjuvant therapy for colon cancer⁹. We need to be aware that if practice changes do occur for any reason that patient care is not compromised. A number of reasons were theorized for the above changes. In the initial waves, it was thought to be with the aim to safely delay surgery, while ensuring patients still received treatment. Also, aiming to avoid clinician exposure led to changes in the utilisation of open vs laparoscopic procedures, particularly based on initial advice^8,9.

Our goal was to assess the impacts of the COVID-19 pandemic on the management of colorectal cancer in regional North Queensland (Australia). Furthermore, we aimed to evaluate whether our vast network had further implications on the delivery of care. Urban centres in Australia have already shown differences in outcomes in colorectal cancer during the pandemic, but we aimed to see if this could be applied to the regional setting.

Methods

A retrospective analysis was performed of 444 patients treated with colorectal cancer both prior to and during the COVID-19 pandemic, at a northern Australian hospital. Patients were identified using multidisciplinary (MDT) meeting lists and coding to assess patients charts to collect data over these timeframes. We aimed to assess all patients treated in our health district with colorectal cancer and tried to confirm this from the electronic medical records using coding data and MDT lists to identify the cohort. The sample size was not calculated for statistical significance prior as it was a retrospective review.

Two times periods were examined:

• pre-COVID-19 March 2017–July 2019 and

• during COVID-19 March 2020–July 2022.

The time periods cover the same duration of time with the second period being since the first COVID-19 wave in Australia/Queensland, when lockdowns began to impact delivery of services. This enabled us to compare similar groups of patients treated with colorectal cancer to assess the outcome measures. Patients were excluded if they were under age 18, did not have colorectal adenocarcinoma or had other benign pathology. Further, they were excluded if they had recurrent disease and if management was not primarily undertaken at this major hospital. The primary outcome measures were the proportion of patients managed emergently with colorectal cancer prior to COVID-19 and during COVID-19 and the number of presentations with advanced disease; defined as T4 tumours, locally advanced cancers and stage III/IV colorectal cancer (CRC).

The secondary outcome measures included; time from referral to endoscopy for patients managed electively. We also compared time from diagnosis, to review in surgical outpatients (OPD). We then looked at the time between OPD review and definitive surgery, when patients had elective work-up. Demographic data to ensure comparable groups was also composed (see Table 1). Complication rates (including both medical and surgical complications – see Table 2) and overall outcomes, that is, length of stay and ICU admission, were also collated. Factors such as obesity, smoking status (ex-smoker at least 1 pack year), indigenous background, and other measures, including ECOG and ASA were analysed. A secondary analysis was performed to compare the impact of distance on treatment and outcomes in patients that travelled for definitive management compared to local patients. Patients who were not from the local city area, defined by city council limits, were considered ‘distant’ patients.

Table 1.

Breakdown of demographic data for patients that were managed invasively prior to and during COVID -19.

Demographic data	Pre COVID-19	During COVID-19	Total
Sex
Male	129 (65.8%)	122 (59.5%)	251 (62.6%)	P =0.192
Female	67 (34.2%)	83 (40.5%)	150 (37.4%)
Age at treatment, Median (IR interquartile range)	65 (55–74)	67.5 (57.25–75)
Operative patients:
BMI (KG/m2)
<25	56	55	111	P =0.463
25–30	60	65	125
>30	60	80	140
Smoking status
Current	28	39	67	P =0.522
Ex-smoker	66	67	133
Nonsmoker	80	82	162
ATSI (Indigenous) Aboriginal or Torres Straight Islander (indigenous Australian)
Yes	13	12	25	P =0.683
No	161	176	337
ECOG (performance status scale)
0	136	137	273	P =0.40
1	24	38	62
2	11	9	20
3	3	4	7
ASA (American Society of Anesthesiologists classification)				P =0.56
1	1	3	4
2	75	72	147
3	101	97	198
4	11	16	27

Table 2.

Breakdown of medical and surgical complications in patients managed surgically or endoscopically.

Type of complication (Medical)	PreCOVID-19	During COVID-19
DVT/PE (within clinical features/imaging)	1 (5.9%)	1 (3.8%)
Pneumonia/Aspiration	2 (11.8%)	4 (15.4%)
Cardiac	1 (5.9%)	2 (7.7%)
UTI/Urosepsis	2 (11.8%)	4 (15.4%)
Delerium	2 (11.8%)	2 (7.7%)
Portal vein thrombus	0	1 (3.8%)
Anaphylaxis	1 (5.9%)	0
Acidosis/Electrolyte disturbance	0	3 (11.5%)
Acute renal injury	2 (11.8%)	3 (11.5%)
Bacteraemia	0	1 (3.8%)
Pressure area	1 (5.9%)	0
Adrenal crisis	1 (5.9%)	0
Pain	2 (11.8%)	2 (7.7%)
Arterial line complication	0	1 (3.8%)
Unplanned ICU Admission	1 (5.9%)	1 (3.8%)
Death (to medical complication)	1 (5.9%)	1 (3.8%)
Total	17	26
Type of complication (Surgical)	PreCOVID-19	During COVID-19
Wound infection/superficial dehiscence	5 (15.1%)	9 (20%)
Deep dehiscence (fascial)	1 (3%)	0
Deep collection (intra-abdominal/pelvic)	4 (12.1%)	6 (13.3%)
Anastomotic leak	3 (9.1%)	5 (11.1%)
Prolonged ileus	7 (21.2%)	9 (20%)
Early small bowel obstruction	2 (6.1%)	2 (4.4%)
Urinary retention	2 (6.1%)	2 (4.4%)
Ureteric injury	1 (3%)	0
Uretheral injury	0	2 (4.4%)
Bladder injury	1 (3%)	0
Anastomotic bleed	2 (6.1%)	2 (4.4%)
Intra-abdominal bleed	1 (3%)	1 (2.2%)
Wound bleed – return operating theatre	1 (3%)	1 (2.2%)
Stoma complication	1 (3%)	2 (4.4%)
High stoma output (readmission >1 l daily)	2 (6.1%)	2 (4.4%)
Stoma site obstruction	0	1 (2.2%)
Re-operation (reason not disclosed)	0	1 (2.2%)
Total	33	45

Statistics

All statistics were examined using SPSS Statistics for Windows; SPSS Statistics for Windows, Version 27.0: IBM Corp. and RStudio Team (2015) version 0.99.486, Integrated Development for R. RStudio, Inc. For comparison of categorical variables, Pearson χ ² or Fisher's Exact Test was used depending on the expected cell count >5. For assessment of continuous data Mann–Whitney U-test was used. A P-value of <0.05 was considered to be statistically significant. Patients with missing data were excluded and not included in the statistical analysis.

Ethics

Local ethics approval was obtained for data and patient data remained deidentified for statistical analysis

Results

A total of 444 patients were identified over the two time periods; 43 patients were excluded, either due to insufficient follow-up or diagnoses that did not meet the initial criteria. Some of these patients were managed in different areas or hospitals and did not meet the selection criteria. A total of 401 were included in the final analysis – 196 prior to COVID-19 (group 1) and 205 during COVID-19 (group 2). There was a higher proportion of male patients, 251 vs 150 female patients (62.6 vs 37.4%). Rectal cancer made up a large proportion of the overall group 154/401 patients (38%). A breakdown of the demographic data can be seen in Table 2 and tumour characteristics in Table 3.

Table 3.

Treatment characteristics comparing groups prior to and during COVID-19, highlighted p values are statistically significant.

	Pre-COVID-19 (n, %)	During COVID-19 (n, %)	Total (n, %)
Surgery emergency or elective
Emergency	17 (9.8%)	37 (19.7%)	54 (14.9%)	P=0.008
Elective	157 (90.2%)	151 (80.3%)	308 (85.1%)
Patient location - local vs distant
Local	101 (51.5%)	107 (52.2%)	208 (51.9%)	P=0.894
Distant	95 (48.5%)	98 (47.8%)	193 (48.1%)
Tumour stage
Stage I	35 (18.5%)	44 (21.7%)	79 (20.2%)	P=0.837
Stage II	49 (25.9%)	54 (26.6%)	103 (26.3%)
Stage III	67 (35.4%)	65 (32%)	132 (33.7%)
Stage IV	38 (20.1%)	40 (19.7%)	78 (19.9%)
Days between referral and colonoscopy - median (IR)	36 (14–68)	26.5 (11.25–50)		P=0.047
Days between colonoscopy and first clinic review - median (IR)	14 (8–24.5)	17 (8–27.5)		P=0.529
Days between first clinic review and definitive surgery - median (IR)	32 (22–88)	29 (12.75–95.5)		P=0.111
Distance from Townsville if not local- median km (IR)	201 (113–386)	166.5 (97–385.25)		P=0.316
Tumour location
Rectum	68 (34.7%)	86 (42%)	154 (38.4%)	P=0.135
Colon	128 (65.3%)	119 (58%)	247 (61.6%)
Operative approach
Open	48 (28.2%)	67 (37.4%)	115 (33%)	P=0.068
Laparoscopic	122 (71.8%)	112 (62.6%)	234 (67%)
Postoperative complications
Yes	50 (25.5%)	71 (34.6%)	121 (30.2%)	P=0.047
No	146 (74.5%)	134 (65.4%)	280 (69.8%)
Length of inpatient stay days - mean (IR interquartile range)	6 (5–12)	6 (5–12)		P=0.812
Admission to ICU
Yes	18 (9.2%)	28 (13.7%)	46 (11.5%)	P=0.160
No	178 (90.8%)	177 (86.3%)	355 (88.5%)
Neoadjuvant therapy
Yes	50 (27.5%)	46 (24.2%)	96 (25.8%)	P=0.472
No	132 (72.5%)	144 (75.8%)	276 (74.2%)
Adjuvant therapy
Yes	85 (47.5%)	72 (38.7%)	179 (49%)	P=0.09
No	94 (52.5%)	114 (61.3%)	186 (51%)

Of the patients managed invasively either surgically or endoscopically, we found a statistically significant difference in emergency presentations. Three patients were managed endoscopically precovid (all endoscopic resection) and six in the postcovid period (one patient had an endoscopically placed stent for obstruction. In the first group prior to COVID-19, 174 patients’ required invasive management, while in the second group during there were 188 patients managed surgically or endoscopically. Of the patient managed prior to covid, 17/174 (9.8%) patients required emergency interventions, during COVID-19 this number increased to 37/188 (19.7%) P =0.008. Table 4 summarises the indications for emergency surgery.

Table 4.

Reason for emergency surgery during and prior to COVID-19.

Reason for emergency surgery	PreCOVID-19	During COVID-19
Bowel perforation	4 (23.5%)	3 (8.1%)
Large Bowel Obstruction	10 (58.8%)	31 (83.8%)
Pain	3 (17.6%)	3 (8.1%)
Total	17	37

There was no significant difference in cancer staging at presentation across the two time periods. There was a slight increase in open surgery during COVID-19 67/179 (37.4%) compared to 48/170 (28.2%) managed laparoscopically. But this difference was not statistically significant P =0.068; only patients managed operatively were looked at in this analysis, and there were some managed endoscopically or with transanal excision not included.

A higher complication rate was found during COVID-19 34.6 vs 25.5% prior to COVID-19 (P =0.046). During COVID-19 the median time between GP referral and colonoscopy was actually lower than prior to COVID-19 26.5 vs 36 days (P=0.047). There was no notable differences found in the time between colonoscopy and review in clinic or to definitive surgery between the two time periods. Adjuvant therapy and neoadjuvant treatment rates were utilised at similar rates prior to and during COVID-19.

Further analysis of patients based upon whether they were local or travelled from a distant location for management was also undertaken. The characteristics of the patients from a local area vs distant location are presented in Table 5. Data was complete for 398 of the original 401 patients, allowing analysis of these patients. Some of the patients the referral letters were not available as they had been referred from different healthcare district, hence were excluded.

Table 5.

Patient and treatment characteristics comparing local vs distant patient - highlighted P-value are statistically significant.

Patient characteristics	Local (n, %)	Distant (n, %)	Total (n, %)
Tumour stage
Stage I	44 (20.7%)	34 (19.3%)	78 (20.1%)	P=0.939
Stage II	56 (26.3%)	46 (26.1%)	102 (26.2%)
Stage III	69 (32.4%)	62 (35.2%)	131 (33.7%)
Stage IV	44 (20.7%)	34 (19.3%)	78 (20.1%)
Days between referral and colonoscopy - median (IR)	32 (13–62)	25.5 (8.75–57.25)		P=0.163
Days between colonoscopy and first clinic review - median (IR)	13 (8–22)	18 (9.25–30)		P=0.006
Days between first clinic review and definitive surgery - median (IR)	29 (15–71)	35 (19–106)		P=0.064
Treatment characteristics
Operative approach
Open	76 (39.1%)	41 (26.5%)	117 (33.5%)	P=0.012
Laparoscopic	118 (61.1%)	114 (73.5%)	232 (66.5%)
Post-op complications
Yes	54 27.3%)	54 (33%)	108 (29.8%)	P=0.242
No	144 (72.7%)	110 (67%	254 (70.2%)
Length of inpatient stay days - mean (IR interquartile range)	6 (4-11.25)	7 (5–12.5)		P=0.195
Admission to ICU
Yes	21 (9.6%)	25 (13.9%)	46 (11.5%)	P=0.186
No	197 (90.4%)	155 (86.1%)	352 (88.5%)
Neoadjuvant therapy
Yes	38 (18.9%)	49 (30.4%)	87 (24%)	P=0.018
No	163 (81.1%)	112 (69.6%)	275 (76%)
Adjuvant therapy
Yes	89 (44.5%)	66 (40.7%)	155 (42.8%)	P=0.047
No	111 (55.5%)	96 (59.3%)	207 (57.2%)

Of interest in our patient data was the distance travelled for treatment for those patients not living locally in the town in which our hospital is based. The median range of travel was 200 km for nonlocal patient with some travelling nearly 1000 km from very remote areas, to have definitive management at this hospital. From the total number analysed, 177 patients were not from the local area (177/398)=44.4%. When comparing the groups, we found a decrease in the use of neoadjuvant therapy use in local – 38/201 (18.9%) vs distant patients 49/161 (30.4%) P=0.018. There was also an increased number of patients managed with open surgery if they were local 76/194 (39.1%) vs 41/155 (26.5%) P =0.012.

An increase in time between colonoscopy and OPD was seen in patients not from the local area 13 vs 18 days (P =0.006). There was no significant difference in complication rates in patients whether they were local 54/198 (27.3%) or distant 54/164 (33%) P =0.242.

Discussion

At the time of collecting this data Queensland had been experiencing yet another wave of COVID-19 as well as further impacts on delivery of elective procedures. Regional and remote Queensland face some unique issues with regards to distance to access to services; this also needs to be factored into the delivery of healthcare. How to best manage this going forward to prevent negative impacts on patient outcomes is paramount. Here, we present our data from a single tertiary hospital, covering a large catchment area during the first COVID-19 wave, and compare it to a similar pre-COVID-19 cohort.

Our data would support an increase in emergency procedures seen in other parts of the world, which can potentially have a negative effect on patient outcomes. We suspect that this is likely due to the fact that patients were reluctant to see the GP with early symptoms and thus were not referred for endoscopic examination. There were also increased complication rates during COVID-19, which is likely impacted by a number of factors; however, increased emergency presentations may be implicated. We did not assess the complications in separate groups other than medical vs surgical, so those including iatrogenic complications cannot be accounted for. In some studies, though, there has been increased complication rates seen in emergency surgery for colorectal cancer during the COVID-19 pandemic⁶.

Interestingly, we found a longer time between GP referral to endoscopic examination prior to COVID-19, than during the COVID-19 pandemic. This would indicate that delayed work-up is not the only factor linked to emergency presentation with CRC. Shaukat and Levin¹⁰ proposed that given the delay in screening endoscopy, the screening tests we use must take into consideration the potential for more advanced polyps and cancer detection.

We found that patients travelling for treatment had different treatment profiles, such as increased utilisation of neoadjuvant therapy. This is likely related to the fact that there was a higher frequency of rectal cancers in the group from distant locations. Further assessment of these treatment profiles is important, as travel and distance to care could be affected by lockdowns or potential for further pandemics. Especially given in our hospital we treat patients from up to 1000 k away. Given we did not separate the rectal cancers subgroup analysis may be required to further examine this, please see our limitations discussed later.

Disease factors are also important as the groups may not be comparable based upon distance to treatment alone. In our cohort, we have a large referral base to our south for rectal cancers as their hospital will perform colon cancer operations but not definitive surgery for rectal cancer. These trends should be remembered and when not treating local patients it is important to be aware of potential confounding factors. It is important to be prepared for how we deliver treatment for colorectal cancers in the future to prevent negative impact to the patients. We did not see any significant changes in complication rates based upon local vs distant patients, however, subgroup analysis of a larger cohort would be required to assess whether distance alone impacts outcomes.

Across the world, telehealth has been utilised to avoid face-to-face review of patients and risk to clinicians at the height of the pandemic, including our health district using such strategies may allow risk assessment to better facilitate appropriate triage of referrals for endoscopy¹¹. Systems to assess the urgency of referrals has also been looked at the in UK in an attempt to ensure urgent referrals are worked up in a timely fashion¹². The triage category of referrals, that is, category 1 <30 days vs category 2 30–90 days will impact the time of diagnostic colonoscopy and could therefore delay diagnosis. When combined with delays in procedures and clinic appointments, all of these factors can potentially lead to interruptions in definitive management for our patients. Shinkwin et al.⁶ found that decreased diagnostic capabilities such as endoscopy and CT Colonography during COVID-19 waves which is yet to recover to previous rates. How to approach such disruptions is vital to ensure that cancer diagnoses are not delayed. A study looking at Australian and Canadian data by Worthington et al. used predictive models to assess the potential implications of decreased diagnostic services like colonoscopy. They found that there could be a significant increase in mortality of colorectal cancer with the decreased availability of endoscopy during the COVID-19 waves. Based on the Australian data, a simple increase of 5% in diagnostic and therapeutic services could mitigate the mortality risk¹³. Such goals are achievable with careful planning of the delivery of treatment and care to patients with colorectal cancer.

In using technology going forward, we should aim to use some of the lessons from the pandemic to our advantage. In areas such as regional Queensland, where face-to-face reviews come at great cost and inconvenience for patients, we can be mindful of using telehealth services. Also, online MDT (multidisciplinary team i.e. tumour board) meetings and discussion with colleagues remotely can be continued to be used to improve patient care. Some healthcare districts have shown that increased use of online capabilities can improve patient satisfaction with their experience in the workup and treatment phase. It may also reduce patient stressors and allow those at risk patients who are fearful of the hospital environment to feel more comfortable to attend follow-up¹⁴.

Limitations of this study are its retrospective nature and that only patients definitively managed at a single centre were included. This potentially means that it may not be representative of the impact on the entire country, so we cannot be sure of the true impact without more data. Further data would need to be assessed, ideally from a prospective database to truly understand the impact of the COVID-19 pandemic on colorectal cancer in regional Queensland. This would help to ensure no patients are missed or excluded and that data points can be targeted to improve the quality. Also, examining data from other centres to increase the number of patients and, therefore, the chance of having significant findings should be done, to assess the true impact of COVID-19 on colorectal cancer. Other centres’ in Northern Queensland and regional Australia could be included to assess the impact of COVID-19 on such centres’.

Factors such as distance to health care and specialist services need to be further examined to develop strategies to avoid delays in the diagnosis of colorectal cancer. With regards to our analysis of the use of neoadjuvant treatment, we did not break it down into rectal cancer vs colon cancer and assumed that similar rates were being treated. This could be a cofounding factor in terms of potential higher rates of neoadjuvant treatment seen in the patients not from the local area (see Table 5). Subgroup analysis could be performed to assess rectal cancer patients separately to see if there is a true difference related to the usual treatment patterns as these patients will usually have a higher rate of neoadjuvant therapies.

As the country moves away from hard lockdowns and the less virulent Omicron strain is found in the community the next phase is dealing with the effects of previous delays. Continuing to monitor those patients referred during the height of the pandemic is vital to ensure no further delays in treatment occur. Medical practitioners must be prepared for future pandemics as the world comes to grips with living with the COVID-19 virus and the long-lasting effects this has had on our healthcare system.

Ethical approval

Townsville Hospital and Health Service Audit, Quality and Innovation Review (AQUIRE) Panel Reference number: THHSAQUIRE1492 Project title: The impact of Covid-19 on colorectal cancer in Northern Queensland. Thank you for submitting the above project which was considered by the Townsville Hospital and Health Service (THHS) Audit, Quality and Innovation Review Panel on 17.08.2022 The Townsville Hospital and Health Service (THHS) Audit, Quality and Innovation Review (AQUIRE) Panel was established by the Townsville Hospital and Health Service and aligns to the National Health and Medical Research Council (NHMRC) National Statement on Ethical Conduct in Human Research, 2007 (updated 2018) (Section 5) and the Ethical Considerations in Quality Assurance and Evaluation Activities (NHMRC, March 2014). This project meets the classification of non-research and has been approved for publication / presentation outside of Queensland Health by the Townsville Hospital and Health Service Audit, Quality and Innovation Review Panel.

Consent

No individual consent as retrospective audit and deidentified data.

Source of funding

No funding was sought and all authors contributed to the research.

Author contribution

Dr R.M.: conceptualization, major manuscript author; Dr S.J.: data collection and some conceptualization; Dr T.L.: data collection and minor author to manuscript; Dr F.S.I., Dr A.S., Dr T.S., and Dr K.C.: data collection; Dr J.L.: statistical analysis; Dr J.H.: rewriting draft, data collection and analysis; Dr A.D.C.: project supervisor; Dr C.D.M.: project supervisor.

Conflicts of interest disclosure

There are no conflicts of interest.

Research registration unique identifying number (UIN)

1. Name of the registry: Australian New Zealand Clinical Trials Registry (ANZCTR).

2. Unique identifying number or registration ID: ACTRN12624000396527.

3. Hyperlink to your specific registration (must be publicly accessible and will be checked): https://www.anzctr.org.au/ACTRN12624000396527.aspx.

Guarantor

Dr Richard Maguire.

Data availability statement

Data is protected by local guidelines and access would need to be sought from The Townsville Hospital Ethics department. A summary of deidentified data could be supplied.

Provenance and peer review

Not commissioned, externally peer-reviewed.