Routine surveillance scanning in HNSCC: Lung screening CT scans have value but head and neck scans do not

Post-treatment surveillance imaging in head and neck cancer: a systematic review

BACKGROUND

In patients treated for head and neck cancer, imaging studies are usually obtained within 3-6 months after treatment for assessment of treatment response. After 6 months, most guidelines advocate clinical follow-up, with imaging reserved for patients with clinically suspect or equivocal findings. However, some guidelines do recommend systematic imaging surveillance, and many clinicians tend to include some type of imaging in their follow-up schemes.

OBJECTIVES

This systematic review focuses on the usefulness of routine (systematic) post-treatment imaging surveillance of head and neck cancer beyond the first 3-6-month baseline imaging study.

METHODS

A systematic literature search was conducted using PubMed and Google Scholar. Additional studies were identified by reviewing reference lists. Only original studies and review papers were considered. Results obtained with systematic post-treatment surveillance imaging were compared to symptom-directed imaging and/or clinical finding-directed imaging.

RESULTS

Five hundred twenty-one records were identified through the database search, and 44 additional records were identified through other sources. Forty-eight articles were selected for the final review. Analysis of these records showed that almost half of cases of locoregional recurrences and/or metastases were only detected by imaging (40.9%), and the mean time of detection of recurrent or metastatic disease (11.5 months) was well beyond the period of the first post-treatment scan. Most authors reported superior results with PET-CT when compared to other imaging techniques.

CONCLUSION

Strong arguments were found in favor of systematic imaging surveillance in locoregional advanced head and neck cancer during at least one and preferably 2 years after treatment.

CRITICAL RELEVANCE STATEMENT

Analysis of the selected records showed that almost half of cases of locoregional recurrences and/or metastases were only detected by imaging. This systematic review suggests that imaging may currently be underused in the post-treatment surveillance of patients with head and neck cancer.

KEY POINTS

• This systematic review focuses on the usefulness of long-term systematic imaging surveillance in patients treated for head and neck cancer. • Analysis of 521 articles revealed that systematic imaging allowed the initial detection of locoregional recurrences and/or metastases in more than 40% of patients. • Imaging may currently be underused in the post-treatment surveillance of patients with advanced head and neck cancer.

ACR Appropriateness Criteria® Staging and Post-Therapy Assessment of Head and Neck Cancer

Imaging of head and neck cancer at initial staging and as part of post-treatment surveillance is a key component of patient care as it guides treatment strategy and aids determination of prognosis. Head and neck cancer includes a heterogenous group of malignancies encompassing several anatomic sites and histologies, with squamous cell carcinoma the most common. Together this comprises the seventh most common cancer worldwide. At initial staging comprehensive imaging delineating the anatomic extent of the primary site, while also assessing the nodal involvement of the neck is necessary. The treatment of head and neck cancer often includes a combination of surgery, radiation, and chemotherapy. Post-treatment imaging is tailored for the evaluation of treatment response and early detection of local, locoregional, and distant recurrent tumor. Cross-sectional imaging with CT or MRI is recommended for the detailed anatomic delineation of the primary site. PET/CT provides complementary metabolic information and can map systemic involvement. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Which Factors Affect the Long-Term Survival of Patients With Oral Squamous Cell Carcinoma With Distant Metastasis?

PURPOSE

The development of distant metastases (DMs) in patients with oral squamous cell carcinoma (OSCC) leads to dismal prospects for survival. The present study aimed to identify the risk factors for DM development and long-term survival.

PATIENTS AND METHODS

The present study was a retrospective cohort study of patients with OSCC at a single institution. The predictor variables were age, gender, lymph node classification, histologic grade, neck dissection, infiltrative growth pattern (INF), vascular/lymphatic invasion, perineural invasion (PI), extranodal extension, local recurrence, nodal metastasis, DMs, interval to the diagnosis of DMs, and surgery for DMs. The primary outcome variables were the 5-year overall survival (OS) and median survival time (MST), which were estimated using the Kaplan-Meier method. Cox hazard models were used to identify the risk factors for DM development.

RESULTS

The cohort included 526 patients; the data from 402 were available for analysis. Of these 402 patients, 37 developed DMs. On multivariate analysis, clinical N1 (cN1)-cN2 (hazard ratio [HR], 3.36), moderate/poor differentiation (HR, 2.51), INFc (HR, 3.27), vascular/lymphatic invasion (HR, 2.95), and PI (HR, 2.17) were independent predictors of DM development. The 5-year OS was 84.6% for the non-DM patients and 9.7% for the DM patients, with a MST of 16.9 months. In those with DMs with cN0, the 5-year OS was 18.2% and the MST was 37.2 months. For those with DMs with cN1-cN2, the 5-year OS was 4.7% and the MST was 12.9 months. In patients with an interval to the DM diagnosis of 10.0 months or longer, the 5-year OS was 20.0% and the MST was 38.6 months. In the patients with an interval to the DM diagnosis of less than 10.0 months, the MST was 11.7 months. The 5-year OS of the patients who had undergone pulmonary metastasectomy was 60.0% and the MST of the nonsurgery group was 16.0 months.

CONCLUSIONS

In the patients with DMs, stage cN0 and a late interval to DM diagnosis were associated with long-term survival. Pulmonary metastasectomy could be worth considering to improve survival.