Increasing numbers of cancer patients who are receiving (or about to commence) systemic anti- cancer therapy (SACT) including immunotherapy or radiotherapy (RT), are testing positive for COVID-19. These patients may be symptomatic or asymptomatic from COVID-19.
In relation to the impact on these patients’ cancer treatment, there has been a tendency to wait for PCR tests to return negative (sometimes repeatedly negative) before considering further treatment, even in patients who are clinically fully recovered from COVID-19 infection.
Even when they are clinically recovered, because they are repeatedly PCR test positive, there is a risk that patients will have cancer treatment postponed, to their potential detriment. There is growing evidence of the safety of proceeding with anticancer treatment in this situation.
There remains concern about the potential infectivity of patients repeatedly PCR positive (so called ‘persistent shedders’), and an accompanying document details the infection prevention and control measures to maintain safe management and operation of cancer units in these situations.
The background is best explained by illustrating with a couple of scenarios:
Patient on SACT (or RT) becomes symptomatic with COVID-19 (confirmed on PCR testing):
- treatment is postponed until the patient recovers (with whatever level of treatment for COVID-19 is required) and as a minimum the patient is reassessed a minimum of 10 days (more often after 14 days) after diagnosis/ positive test. If fully recovered, in theory can proceed with cancer treatment.
- often cancer treatment requires further delay until full clinical recovery – acknowledged that this is a cancer team clinical decision – it may be difficult to tease apart all of the symptomatology associated with COVID-19 infection versus underlying cancer or cancer treatment related effects.
- in practice the patient ends up with further testing with a tendency to await swabs returning PCR negative.
- a small number of patients who are clinically recovered (often haematology patients) remain PCR positive for lengthy periods. Advice has been to consider the advisability of proceeding with SACT dependant on the clinical urgency/ benefit but there have been instances of patients who are clinically well having had treatment delayed, altered with potential detriment to their cancer outcome.
Asymptomatic patient tests positive for COVID-19 (e.g. through family/ work contacts):
- patients are delayed for minimum 14 days – if remain asymptomatic can receive SACT or RT – in practice patients are retested – majority are negative and commence SACT – some units ‘require’ two negative tests.
- patients remain PCR positive – then requires clinical decision to determine if treatment continues – in practice a significant delay due to current practice of re-testing.
Depending on the decision of the clinical team (and this varies across Scotland), patients may have treatment postponed unnecessarily, or restrictions on the practicalities of treatment may result in suboptimal treatment being offered e.g. to allow outpatient management instead of inpatient treatment – the aim has been to reduce perceived risk to the patient of overwhelming COVID-19 infection.
The following guidance is issued to clinical teams in cancer centres/units in Scotland:
- further cancer treatment – treatment should be postponed for a minimum of 14 days from onset/ positive test result, and more commonly for 14 days after clinical recovery from COVID-19. It is acknowledged that in some situations (particularly immunocompromised patients e.g. blood cancer patients) the interval to reassessment of further treatment should be 20 days from onset/ positive test result or recovery, whichever is longer.
- there is now no requirement for repeat testing to guide cancer treatment (guidance now is that no further testing should be done until at least 90 days have elapsed after a previous positive COVID-19 PCR test result).
- advice on those patients who remain swab positive – if for whatever reason patients are found to be persistently PCR test positive for COVID-19, then the recommendation remains to base the timing of further cancer treatment on their clinical recovery from COVID-19 clinical features.
For asymptomatic patients
The same recommendations, to those above, hold for patients who are asymptomatic from COVID-19 but have tested positive.
Guidance for the development of standard operating procedures (SOPs) for the safe delivery of systemic anti-cancer therapy (SACT) to patients who have tested positive for SARS-CoV-2 (COVID-19) to be followed – see paper two overleaf.
Note that not all possible scenarios can be covered in this guidance and if a situation presents which is radically different from that contained in this general guidance, teams should liaise with the local Infection Prevention and Control personnel – additional advice is available from local microbiology/virology teams.
Also note that the above does not preclude the continuation of treatment for those where the clinical team deems that the risk of delay outweighs the risk of COVID-19.
SACT/RT sub-group asks clinical teams in cancer units across Scotland to incorporate this into their current practice.