1. Introduction
Cancer in adolescence and young adulthood (AYA), defined as patients aged 15–39 at cancer diagnosis, is uncommon, accounting for 5% of all cancer diagnoses [
1]. Leukemia, lymphoma, testicular cancer, and thyroid cancer are the most common cancers among 15 to 24-year-olds, while breast cancer and melanoma are most common among 25–39-year-olds [
2].
AYA cancer patients face unique developmental, physical, and psychosocial issues that make adjustment to their disease and health maintenance challenging [
3]. AYAs describe unsatisfactory care experiences such as lack of recognition of their autonomy by healthcare providers (HCPs), lack of peer support, and inappropriate care environments [
4,
5]. To address these issues, the United Kingdom (UK) has rapidly expanded the availability of dedicated services for teenagers and young adults (TYA) ages 13 to 24. In contrast, no age-specific care services are available for young adult (YA) cancer patients aged 25 to 39 years.
Historically, progress in survival for AYAs has lagged behind both children and older adults, at least partly due to a prolonged diagnostic pathway [
6,
7,
8]. Recently, we and others showed this gap in survival has closed for most, but not all tumors [
9,
10]. Early diagnosis of cancer is key to facilitate the start of treatment and can improve psychosocial and clinical outcomes [
11,
12,
13]. The cause of prolonged diagnosis among AYA is likely to be multifactorial [
14,
15] and may include a lack of awareness amongst AYAs and HCPs, heterogenous and non-specific symptoms, and the rarity of cancer at this age. Reducing time to diagnosis is a key area for improving cancer care in the National Health Service [
16]. The BRIGHTLIGHT study, assessing specialist care for TYAs with cancer in England [
17], is the largest study among TYA patients looking at diagnostic timeliness [
15]. In this study, over a quarter of participants (27%) waited more than one month to approach an HCP about symptoms [
15].
Although age-specific guidelines to improve diagnostic timeliness in TYAs have been developed in the UK, for YAs, no specific guidance exists [
18]. Information regarding YA’s diagnostic pathway is lacking and often obscured in studies of older adults where most patients are over age 50. As life events and the distribution of cancer types among YAs are distinct compared to older adults, available evidence cannot be extrapolated to YAs.
To improve healthcare services for YAs, we aim to describe the diagnostic pathway of patients aged 25–39 at diagnosis, identify factors associated with a prolonged pathway, compare the time from first symptom to doctor consultation in YAs with that in TYAs, and describe suggestions made by YAs to improve the diagnostic pathway.
5. Discussion
In this study, we investigated the diagnostic pathway of YA cancer patients, examined patient and tumor characteristics associated with the length of the diagnostic pathway, compared the patient interval length of our sample with a TYA cohort, and reported patients’ suggestions for improving the diagnostic pathway.
Both patient and healthcare intervals were long among a substantial proportion of participants. Forty-two percent of participants had patient intervals ≥1 month and 21% ≥3 months. Healthcare intervals were ≥1 month for 40% and ≥3 months for 17% of participants. Gender and ethnicity were not associated with diagnostic intervals or the number of consultations before diagnosis. Age was only associated with the healthcare interval, where age was slightly lower among patients with a >1 month interval. Remarkably, symptom presence at diagnosis did not influence healthcare interval length nor the number of GP or hospital doctor consultations.
Subtype-specific cancer diagnosis was associated with both patient and healthcare interval length and number of pre-diagnosis consultations. YAs with melanoma were most likely to wait ≥1 month before consulting a doctor but never had ≥4 hospital doctor consultations, as expected with identifiable presenting symptoms (an itching or bleeding pigmented lesion) of this cancer. The finding that identifiable presenting symptoms may lead to a short patient interval is supported by a sub-analysis of the BRIGHTLIGHT cohort, which shows 38% of participants with mole changes had a patient interval > 1 month [
24].
YAs with cervical cancer were more likely to wait ≥1 month as well, and some had ≥4 GP consultations. Notably, half of these patients were not detected through screening. However, in the NHS one in four women skip cervical screening, with the proportion increasing to one in three among those aged 25 to 29 [
25]. Unfortunately, our study did not ask cervical cancer patients not detected through screening whether they participated in the screening program. We therefore cannot conclude whether these were interval carcinomas occurring between two screening dates.
In breast cancer, one might expect a short patient interval as breast cancer patients form a distinct group compared to other cancer patients, given the general knowledge about the disease and its symptoms in the population. However, a third waited more than one month before consulting a doctor. We hypothesize this may be due to YAs having busy lives and not recognizing symptoms as caused by malignancy. Two participants with breast cancer reported being diagnosed through screening, possibly in a screening program for a hereditary cancer syndrome. The standard NHS screening program for breast cancer starts at age 50. Regarding the breast cancer healthcare interval, it is unsurprising that few participants had >4 GP (5%) or hospital (3%) consultations.
The NICE two-week-wait rule (TWW) states patients with a suspicion of cancer should be referred to a specialist in two weeks and additional investigations, including biopsies, should be carried out on one day [
26]. Therefore, one would expect the healthcare interval to be shorter than two weeks for most participants. However, the healthcare interval lasted ≥2 weeks in 43% of YAs, and ≥1 month in 16%. As expected, few had a healthcare interval ≥3 months (2%). It is known that younger patients present less often via the TWW, and more often via non-TWW referrals or in emergency presentations, however, this may not be directly correlated with the healthcare interval, as the majority of patients will be diagnosed through emergency presentation [
27].
Participants with diagnoses other than breast cancer were more likely to experience a healthcare interval ≥1 month. The only exception was leukemia, though these patients had many pre-diagnosis GP and hospital consultations. The need to perform additional investigations in leukemia patients to confirm the diagnosis may explain the high number, but most of these investigations can be undertaken and interpreted relatively quickly. Alternatively, patients with leukemia often present as an emergency, although this percentage is higher in TYAs than Yas [
27].
Comparison with existing literature is difficult, as studies focusing solely on YAs 25–39 years of age are rare. This study enabled a direct comparison of YA and TYA patient intervals with findings from the BRIGHTLIGHT study. This showed that YAs in our study, in general, had longer patient intervals. Age-related factors may contribute to this difference, such as differing life priorities (e.g., having a job, taking care of children). The distribution of diagnoses may play an important role as well: the proportion of participants diagnosed with leukemia and lymphoma was larger in the TYA group, whereas carcinomas were diagnosed more often in the YA group. Participants who were male or white were more at risk of a longer patient interval when aged 25–39, compared to those aged 12–24. Furthermore, those diagnosed with lymphoma with a patient interval ≥1 month, or ≥3 months, were also more likely to be older. This was also true for patients with soft tissue sarcoma who had a patient interval ≥3 months. These findings are relevant and call for actions to increase awareness among YAs to reduce the patient interval.
Our findings support those of a European study, showing diagnostic routes among those aged 15–29 vary substantially, and an American study with patients aged 15–29 that found cancer diagnosis was significantly associated with interval length, whereas ethnicity, age, and gender were not [
28]. Similarly, a National Cancer Intelligence Network report found that cancer diagnosis played a major role in determining how TYAs were likely to be referred [
27].
A Danish study amongst AYAs (aged 15–39) reported GP consultations increased several months before cancer diagnosis, possibly reflecting low awareness of patients and HCPs that symptoms may be due to malignancy [
29].
Although 68% of participants felt they were taken seriously in their first consultation, most suggestions to improve the diagnostic pathway were about taking YAs seriously, and not rejecting cancer as a possibility due to age. Additional recommendations were made about communication, and reducing passive waiting time, e.g., for additional examinations, referrals, or requesting information from other institutions. There were no major differences by interval length and most recommendations were not age specific.
To our knowledge, this is the first study to examine the diagnostic pathway of YA cancer patients, with various cancer diagnoses. However, this study has several limitations. First, intervals and the number of consultations were self-reported, potentially introducing recall bias. A generally consistent finding is that as the recall time increases, the ability to recall events degrades [
30]. However, significant events, such as a cancer diagnosis, are less likely to be forgotten [
30]. Furthermore, estimating the duration of an event is extremely stable [
31,
32]. To minimize the effect of recall bias, patients were asked to report the duration of intervals instead of dates, and questions were anchored to a life event (the cancer diagnosis).
Second, the study may be subject to selection bias as only 21% of invited participants responded, which is not unusual for studies among young adults with cancer. Data for the non-responder analysis was unfortunately only available from a selection of patients. However, this analysis does not show any differences in terms of age, time since diagnosis, or diagnosis.
Another cause of selection bias is the survivorship population in which we conducted our study. Not only will these people have had different tumor characteristics (e.g., lower stage at diagnosis), but they may also have had a different diagnostic pathway. Our results should thus be interpreted with this in mind.
Third, the distribution of tumors does not accurately reflect the incidence of cancers in YAs in the population [
10]. For males, the most common cancers among YAs in the UK are testicular cancer, melanoma, and gastrointestinal tumors. For females, these are breast cancer, melanoma, and tumors of the genitourinary tract. Lymphoma and sarcoma are therefore overrepresented in our study, whilst melanoma and gastro-intestinal tumor may be underrepresented. We invited patients from hospitals in the South East, East, and London regions, who may have relatively more TWW referrals than those diagnosed in the North East [
27]. Interval length may be underestimated when compared to the whole of England. Lastly, as subgroups were small, we were unable to perform adjusted analyses and the results should therefore be interpreted with caution.
Our findings highlight that cancer is still seen as a disease of the elderly. We recommend increasing awareness and gain better insight in the diagnostic pathway of patients aged 25–39 and raise awareness in the general public and among health care professionals to shorten time to diagnoses. Further research with a larger population is needed to confirm our findings with respect to identified risk groups, and to study the impact of a prolonged diagnostic pathway on clinical and patient-reported outcomes for YAs.