Keywords:
Head and neck, Thyroid / Parathyroids, Oncology, CT, CT-High Resolution, Decision analysis, Outcomes analysis, Surgery, Outcomes, Cancer, Education and training
Authors:
A. Mahajan, N. Sable, R. Vaish, D. Chaukar, P. Chaturvedi, P. Pai, S. V. Kane, A. Dcruz; Mumbai/IN
DOI:
10.26044/ecr2019/C-1985
Methods and materials
- Retrospective review of clinical database at our center from Jan 2012 to Dec 2016,
104 PTC patients with extrathyroidal extension .
- 20 of these patients were excluded on the basis of the following criteria:inadequate information on the extent of disease intraoperatively and histopathology (15 patients),
Contrast CT examinations were not available (5 patients).
- Final sample consisted of 84 patients
- All patients underwent total or near-total resection of the primary tumor.
Image interpretation:
- All patients underwent contrast-enhanced CT with an MDCT scanner with a reconstructed slice thickness of 3 mm for axial and coronal images
- All CT images were interpreted by two radiologists.
Both readers were blinded to original CT reports and the surgical and pathologic findings.
Imaging Parameters:
- Maximum tumor diameter (cm)
- Tracheal dislocation (mm)
- Posterior membranous portion extension
- Soft tissue in the cartilage with enhancement => tumor
- The degree of tumor encirclement of trachea was classified on the following 5-point scale: 0,
no encirclement;1,
tumor in contact with 1–89° of the circumference of each structure;2,
90–179°;3,
180–269°;4,
270–360°.
- Tracheal deformity/Shape was classified on the following 3-point scale : Grade I: horseshoe,
elliptical,
circular configuration; Grade II: locally straightened wall; Grade III: inward concave deformity.
CT Shin grading Figure 1:
0: > 5mm distance between tumor and trachea.
I: disease abuts external perichondrium.
II: disease invades into the cartilage +/- destruction.
III: disease extends into the tracheal mucosa with no elevation/penetration of mucosa.
IV: disease is full-thickness invasion with expansion of the tracheal mucosa with a bulge
Modified Shin Staging:
Invasion of the trachea was deemed present when at least two of the following CT criteria were fulfilled:
Tumor in contact with 180° or more of the tracheal circumference (grades 3 and 4)–Deformity of the tracheal lumen at the level of the mass (grade 2 and 3)+/- displacement–Soft tissue in the cartilage with enhancement => tumor
Or
Focal irregularity,
thickening,
or bulging in the mucosal portion of trachea adjacent to the mass (SHIN 4).
Statistical analysis:
- Interobserver agreement was determined by calculating kappa values.
- The sensitivity,
specificity,
PPV,
NPV,
and accuracy of CT findings and SHIN score were calculated with surgical and histopathologic findings as the standard of reference.
- Univariate and Multivariate analysis was performed using chi-square and logistic regression model resp.