<p class="first" id="d688961e136">The immediate perioperative period (days before
and after surgery) is hypothesized
to be crucial in determining long-term cancer outcomes: during this short period,
numerous factors, including excess stress and inflammatory responses, tumour-cell
shedding and pro-angiogenic and/or growth factors, might facilitate the progression
of pre-existing micrometastases and the initiation of new metastases, while simultaneously
jeopardizing immune control over residual malignant cells. Thus, application of anticancer
immunotherapy during this critical time frame could potentially improve patient outcomes.
Nevertheless, this strategy has rarely been implemented to date. In this Perspective,
we discuss apparent contraindications for the perioperative use of cancer immunotherapy,
suggest safe immunotherapeutic and other anti-metastatic approaches during this important
time frame and specify desired characteristics of such interventions. These characteristics
include a rapid onset of immune activation, avoidance of tumour-promoting effects,
no or minimal increase in surgical risk, resilience to stress-related factors and
minimal induction of stress responses. Pharmacological control of excess perioperative
stress-inflammatory responses has been shown to be clinically feasible and could potentially
be combined with immune stimulation to overcome the direct pro-metastatic effects
of surgery, prevent immune suppression and enhance immunostimulatory responses. Accordingly,
we believe that certain types of immunotherapy, together with interventions to abrogate
stress-inflammatory responses, should be evaluated in conjunction with surgery and,
for maximal effectiveness, could be initiated before administration of adjuvant therapies.
Such strategies might improve the overall success of cancer treatment.
</p>