PET Scan Not Cost Effective for Diagnosing Recurrent Cervical Cancer

The addition of positron emission tomography/computed tomography (PET-CT) to the current standard of care for the diagnosis of recurrent or persistent cervical cancer is not cost-effective, according to the results of a systematic review and meta-analysis funded by the United Kingdom’s National Institute for Health Research Health Technology Assessment program.¹
   
It is known that PET more accurately detects secondary sites of cervical cancer than CT alone.² Because the prognosis is better when the cancer is detected in its early stages, some have proposed monitoring asymptomatic patients using advanced imaging studies, such as PET-CT, for signs of recurrence. However, the cost-effectiveness of using PET-CT for routine screening for cancer recurrence is not well studied.
   
The current treatment strategy for evaluating cervical cancer recurrence is clinical examination and MRI alone or in conjunction with CT scanning. In this analysis, researchers sought to determine whether the addition of PET-CT scanning is effective and whether the cost of the scan is justified.¹
   
Twelve small studies, most of which included women who had symptoms indicative of cancer recurrence, were included in the evaluation of imaging accuracy, and 62 studies were assessed in the effectiveness review. In the effectiveness study, however, none of the included studies evaluated cisplatin monotherapy, which in the National Health Service is the most commonly administered chemotherapeutic agent for cervical cancer.
   
Meta-analysis of studies evaluating PET-CT scans determined the specificity and sensitivity to be 92.2% and 88.1%, respectively. The sensitivities and specificities for MRI scans ranged from 82% to 100% and 78% to 100%, respectively, and those for CT scans ranged between 78% and 93% and between 0% and 95%, respectively. The one study that directly compared PET-CT with older imaging methods showed that PET-CT was associated with more true positives and fewer false-negatives. However, the opinion of 21 clinical experts was that the mean increase in accuracy from the addition of PET-CT was less than the minimum important difference in accuracy required to justify routinely adding PET-CT to the standard monitoring of women who have completed primary treatment.
   
The researchers found that the incremental cost-effectiveness ratios for all models were more than $1.5 million per quality-adjusted life-year and the added cost per additional case of recurrence was nearly $1 million. This significant increase in cost, coupled with the slight increase in accuracy, does not justify adding PET-CT to standard practice for the diagnosis of recurrent or persistent cervical cancer, the researchers concluded.

Pertinent Points:
- Adding PET-CT to standard practice for the diagnosis of recurrent or persistent cervical cancer is not cost-effective.
- Guidelines that recommend costly imaging studies, such as PET-CT, for recurrent cervical cancer should be reconsidered.
 

References:

1. Meds C, Auguste P, Davenport C, et al. Positron emission tomography/computerized tomography imaging in detecting and managing recurrent cervical cancer: systematic review of evidence, elicitation of subjective probabilities and economic modeling. Health Technol Assess. 2013;17(12):1-323. doi: 10.3310/hta17121.
2. Grigsby PW, Siegel BA, Dehdashti F. Lymph node staging by positron emission tomography in patients with carcinoma of the cervix. J Clin Oncol. 2001;19;3745-3749.