Fellows’ Journal Club

The authors analyzed 1.5T MRI examinations of 100 consecutive patients treated with radiation therapy with or without additional surgery for head and neck squamous cell carcinoma. MRI examinations included morphologic sequences and DWI. Histology and follow-up served as the standard of reference. Two readers, blinded to clinical/histologic/ follow-up data, evaluated images according to clearly defined criteria for the diagnosis of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment, post-radiation therapy inflammatory edema, and late fibrosis. They conclude that adding precise morphologic MRI criteria to quantitative DWI enables reproducible and accurate detection of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment.

Abstract

Figure 3 from paper
DWI MRI obtained 3 months after RTH and bucopharyngectomy for squamous cell carcinoma of the retromolar trigone. The patient had right reflex otalgia and progressing trismus. Endoscopy could not be performed. Axial T2 (A) and coronal STIR (B) images show a triangular, elongated, strongly hypointense lesion (arrows) on the right. There was no contrast enhancement (not shown). The diagnosis of benign post-RTH late fibrosis was made. The b=1000 image (C) reveals low signal. ADC map (D) likewise shows low signal (ADC mean = 0.731 × 10−3 mm2/s). Follow-up at 38 months (not shown) showed no recurrence but progressive scar retraction on MRI.

BACKGROUND AND PURPOSE

Although diffusion-weighted imaging combined with morphologic MRI (DWIMRI) is used to detect posttreatment recurrent and second primary head and neck squamous cell carcinoma, the diagnostic criteria used so far have not been clarified. We hypothesized that precise MRI criteria based on signal intensity patterns on T2 and contrast-enhanced T1 complement DWI and therefore improve the diagnostic performance of DWIMRI.

MATERIALS AND METHODS

We analyzed 1.5T MRI examinations of 100 consecutive patients treated with radiation therapy with or without additional surgery for head and neck squamous cell carcinoma. MRI examinations included morphologic sequences and DWI (b=0 and b=1000 s/mm2). Histology and follow-up served as the standard of reference. Two experienced readers, blinded to clinical/histologic/follow-up data, evaluated images according to clearly defined criteria for the diagnosis of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment, post-radiation therapy inflammatory edema, and late fibrosis. DWI analysis included qualitative (visual) and quantitative evaluation with an ADC threshold.

RESULTS

Recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment was present in 36 patients, whereas 64 patients had post-radiation therapy lesions only. The Cohen κ for differentiating tumor from post-radiation therapy lesions with MRI and qualitative DWIMRI was 0.822 and 0.881, respectively. Mean ADCmean in recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment (1.097 ± 0.295 × 10−3 mm2/s) was significantly lower (P < .05) than in post-radiation therapy inflammatory edema (1.754 ± 0.343 × 10−3 mm2/s); however, it was similar to that in late fibrosis (0.987 ± 0.264 × 10−3 mm2/s, P > .05). Although ADCs were similar in tumors and late fibrosis, morphologic MRI criteria facilitated distinction between the 2 conditions. The sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (95% CI) of DWIMRI with ADCmean < 1.22 × 10−3 mm2/s and precise MRI criteria were 92.1% (83.5–100.0), 95.4% (90.3–100.0), 92.1% (83.5–100.0), 95.4% (90.2–100.0), 19.9 (6.58–60.5), and 0.08 (0.03–0.24), respectively, indicating a good diagnostic performance to rule in and rule out disease.

CONCLUSIONS

Adding precise morphologic MRI criteria to quantitative DWI enables reproducible and accurate detection of recurrent head and neck squamous cell carcinoma/second primary head and neck squamous cell carcinoma occurring after treatment.

Read this article: http://bit.ly/2v5gFuI

The post MRI with DWI for the Detection of Posttreatment Head and Neck Squamous Cell Carcinoma: Why Morphologic MRI Criteria Matter appeared first on AJNR Blog.



Credits:

Original Content Source