Late relapse (LR) of testicular cancer is rare, especially more than 5 years after treatment, according to the findings of a population-based study presented at the 2022 ASCO Annual Meeting.
In addition, the study showed a decrease in LR rates and mortality over a nearly 3-decade period among patients with metastatic disease initially treated with chemotherapy.
“We believe centralization of treatment, adherence to guidelines, and continuous evaluation of results are key to these improved outcomes,” lead investigator Torgrim Tandstad, MD, PhD, of St Olav’s University Hospital in Trondheim, Norway, said during the meeting.
Using the Cancer Registry of Norway and Norwegian Cause of Death Registry, Dr Tandstad and colleagues identified 5712 patients diagnosed with testicular cancer from 1980 to 2009 (2978 seminoma and 2734 nonseminoma).
The investigators divided patients into 2 cohorts based on when they were diagnosed: 1980-1994 (2207 patients) and 1995-2009 (3505 patients). The team defined LR as relapse occurring more than 2 years after treatment. They also examined the rates of very late lapse (VLR) and extremely late relapse (XLR) — occurring more than 5 years and more than 10 years after treatment, respectively.
Of 472 patients who had a relapse, 63% experienced it within 2 years after treatment. The median time to relapse was 0.7 years. LR occurred at a median of 4.7 years after treatment. LR occurred in 109 patients (23%), 50 patients (10.5%) had a VLR, and 17 (3.5%) had an XLR.
Among 3999 patients with clinical stage I disease, LR occurred in 61 patients (1.9%), VLR in 29 (1.0%), and XLR in 10 (0.5%). The LR rates in these patients were higher for those managed with surveillance compared with those receiving adjuvant therapy (4.0% vs 0.9%), Dr Tandstad reported.
Of the 61 patients with LR, 8 died, 4 from testicular cancer or its treatment. The 10-year overall survival (OS) and cancer-specific survival (CSS) rates were 76.8% and 81.4%, respectively.
Dr Tandstad said the relatively low rate of relapse in clinical stage I disease in Norway corresponds to extensive use of adjuvant treatment for seminal and nonseminal cancers.
Among 1713 patients with metastatic disease, LR, VLR, and XLR occurred in 48 (3.6%), 21 (1.6%), and 7 (0.8%) of patients, respectively. Of the 48 patients with LR, 24 died, 17 from testicular cancer or its treatment.
For patients with metastatic disease initially treated with chemotherapy, the 10-year OS rate following LR was 49.7% for those diagnosed in 1980-2009. The 10-year OS rate increased over time, from 34.6% for those diagnosed in 1980-1994 to 60.9% for those diagnosed in 1995-2009.
The investigators observed a similar pattern for CSS. The 10-year CSS rate increased from 38.6% for those diagnosed in 1980-2009 to 64.6% for those diagnosed in 1995-2009.
Tandstad T, Hellesnes R, Haugnes HS, et al. Late relapses in testicular cancer: Results from a national cohort. Presented at ASCO 2022; June 3-7, 2022. Abstract 5008.