Immuno-oncology: universally applicable or age-dependent?

Immuno-oncology has been groundbreaking and provided patients with more valuable months of life. However, response rates still remain low at around 25%, and immunotherapy success in relation to age needs further research.

Meta-study examines immunotherapy and patient age

Immuno-oncology has set completely new opportunities in urology and provides some patients with a few more valuable months of life at the end of tumor therapy. However, the response rates are still low at around 25%, and the influence of age on the success of immunotherapy has also been poorly investigated until present. A recent review has now shown that age could play a role in this and calls for more research to develop in this topic.

It almost seems that immuno-oncology (also referred to as cancer immunotherapy) is the new shining star in the therapy sky for uro-oncology. Many patients also have high hopes for the currently fast-developing antibody therapies. However, most patients with urological tumors are around 65 years of age or older.

Based on experience, and supported by numerous studies, the practicing physician knows that, on the other hand, people above the age of 60 are subject to progressive immune system senescence and their T-cell numbers are constantly decreasing. So how can it be explained that immuno-oncology is almost ubiquitously applied and, at least in urology, often at a later age?

The fact is that the influence of age on the success of immunotherapy, for example with PD1- or PD-L1-binding antibodies, is currently only insufficiently investigated, but could have concrete effects on therapy success and the associated hopes of patients and doctors alike. 

To answer this question, Dr. Aly-Khan A. Lalani and colleagues searched medical databases such as PubMed/Medline, Embase, Web of Knowledge and the Cochrane Library for work up to the publication date of October 2017. 21 studies were included in the evaluation, four times on prostate carcinoma (PC), eight times on urothelial carcinoma (UC) and nine times on renal cell carcinoma (RCC).

In some immuno-oncological approaches, age is relevant

Sipuleucel-T, a therapeutic cancer vaccine for PC, which contains prostate-specific acid phosphatase as an essential antigenic component, increased the survival of patients in a median age > 70 years in studies.

In the metastatic UC studies, patients were usually over 65 years of age. Three studies showed similar response rates in cancer patients < 65 years and > 65 years. In a study in which patients were younger or older than 80 years, treatment with checkpoint inhibitors (e.g. atezolizumab) achieved comparable response rates.

Another vaccine-based study also found that the survival of patients > 65 years with metastatic RCC could be reduced.

However, the data on nivolumab, another checkpoint inhibitor, was particularly interesting. The second-line therapy with RCC showed that the therapeutic success was much more manifest in patients between 65 and 75 years of age compared to older participants beyond the age of 75. 

The study evaluation by Dr. Lalani and colleagues shows that the age of a tumor patient could have an influence on the success of treatment in some settings, but the data situation is still very inaccurate. However, this issue should certainly be addressed in the context of patient education about the novel immunological therapy options.

Lalani, AA; Bossé, D.; McGregor, BA; Choueiri, TK; Immunotherapy in the Elderly, Eur Urol Focus. 2017 Oct;3(4-5):403-412.
doi: 10.1016/j.euf.2017.11.008. Epub 2017 Nov 26.