Dual-Layer Spectral CT Imaging of Upper Aerodigestive Tract Cancer: Analysis of Spectral Imaging Parameters and Impact on Tumor Staging

BACKGROUND AND PURPOSE

Dual-layer spectral CT is a novel technology that utilized conventional single-tube CT acquisition with a dual-layer detector for the separation of high and low-energy photons to create spectral data for material decomposition. We evaluated the spectral parameters of iodine density and Z-effective values in primary head and neck squamous cell carcinoma and determined its impact on local tumor staging.

MATERIALS AND METHODS

Twenty-one patients with primary head and neck squamous cell carcinoma and 15 healthy controls were retrospectively evaluated. Iodine density (milligram/milliliter) and Z-effective values were compared quantitatively between head and neck squamous cell carcinoma and normal neck mucosa. The receiver operating characteristic area under the curve determined the diagnostic performance of the spectral data for local staging. We compared conventional CT images without and with iodine density and Z-effective images to determine its impact on local tumor staging.

RESULTS

Primary head and neck squamous cell carcinoma showed higher mean iodine density (2.01 [SD, 0.26] mg/mL, P < .001) and Z-effective values (8.21 [SD, 0.36], P < .001). A high interobserver correlation was demonstrated for ROI measurements for both the control group (iodine density, κ = 0.71, and Z-effective values, κ = 0.78) and head and neck squamous cell carcinoma (iodine density, κ = 0.84, and Z-effective values, κ = 0.75) group. The area under the curve for iodine density and Z-effective values was 0.98 and 0.93, respectively. Optimal thresholds were identified as 1.58 mg/mL (95% CI, 1.45-1.71 mg/mL; P < .001; sensitivity = 1.0; specificity = .0.93) for iodine density and 8.08 (95% CI, 7.96-8.19; P < .001; sensitivity = 0.86; specificity = 0.93) for Z-effective values. Conventional CT with the addition of dual-layer spectral data (iodine density and Z-effective values) improved the accuracy of local tumor staging in 3 of 21 patients (14%) with head and neck squamous cell carcinoma compared with the criterion standard surgical staging/histopathology.

CONCLUSIONS

Dual-layer spectral iodine density and Z-effective values provided increased quantitative and qualitative differentiation between upper aerodigestive head and neck squamous cell carcinoma and normal mucosa. Increased tissue differentiation improved the local tumor staging accuracy.

Prehabilitation is feasible in patients with rectal cancer undergoing neoadjuvant chemoradiotherapy and may minimize physical deterioration: results from the REx trial

AIM

Rectal cancer patients undergoing neoadjuvant chemoradiotherapy (NACRT) experience physical deterioration and reductions in their quality of life. This feasibility study assessed prehabilitation (a walking intervention) before, during and after NACRT to inform a definitive multi-centred randomized clinical trial (REx trial).

METHODS

Patients planned for NACRT followed by potentially curative surgery were approached (August 2014-March 2016) (www.isrctn.com; 62859294). Prior to NACRT, baseline physical and psycho-social data were recorded using validated tools. Participants were randomized to either the intervention group (exercise counselling session followed by a 13-17 week telephone-guided walking programme) or a control group (standard care). Follow-up testing was undertaken 1-2 weeks before surgery.

RESULTS

Of the 296 screened patients, 78 (26%) were eligible and 48 (61%) were recruited. N = 31 (65%) were men with a mean age of 65.9 years (range 33.7-82.6). Mean intervention duration was 14 weeks with 75% adherence. n = 40 (83%) completed follow-up testing. Both groups recorded reductions in daily walking but the reduction was less in the intervention group although not statistically significant. Participants reported high satisfaction and fidelity to trial procedures.

CONCLUSION

This study demonstrates that prehabilitation is feasible in rectal cancer patients undergoing NACRT. Good recruitment, adherence, retention and patient satisfaction rates support the development of a fully powered trial. The effects of the intervention on physical outcomes were promising.

Changes in Patient-reported Swallow Function in the Long Term After Chemoradiotherapy for Oropharyngeal Carcinoma

AIMS

To assess long-term patient-reported swallow function after chemoradiotherapy for oropharyngeal carcinoma and to evaluate the frequency of deterioration/improvement over years.

MATERIALS AND METHODS

Fifty-nine patients with oropharyngeal carcinoma treated with parotid-sparing intensity-modulated radiotherapy and concurrent chemotherapy between 2010 and 2012 had previously completed the MD Anderson Dysphagia Inventory (MDADI) at a median of 34 months (range 24-59) after treatment. An MDADI was posted to 55 alive and disease-free patients after a 30 month interval; 52/55 replies were received, a median of 64 months (range 52-88) after treatment; 27/52 (52%) had been managed with a prophylactic gastrostomy. A 10 point or greater change in the MDADI scores was defined as clinically significant.

RESULTS

Overall, in the whole cohort, patient-reported swallow function showed a small absolute improvement in MDADI composite score on the second MDADI questionnaire (>5 years after treatment) compared with the first MDADI (>2 years after treatment); mean 68.0 (standard deviation 19.3) versus 64.0 (standard deviation 16.3), P = 0.021. Using the composite score, swallow function was stable over time in 29/52 (56%) patients; a clinically significant improvement in swallow function over time was noted in 17/52 (33%) patients; conversely 6/52 (12%) patients experienced a clinically significant deterioration with time. Abnormality of pre-treatment diet and a prophylactic gastrostomy correlated with an inferior MDADI composite score on the later questionnaire (P = 0.029 and P = 0.044, respectively).

CONCLUSIONS

Long-term dysphagia is prevalent >5 years after treatment. Although long-term swallow function is stable in most patients, it is not static in a minority. On MDADI composite summary scores, 33% of patients experienced an improvement, whereas 12% deteriorated with time. Further investigation is needed to determine underlying mechanisms behind these divergent outcomes.

Late stenosis of a superficial temporal-middle cerebral artery bypass: angiographic and histological findings

The course of a patient with an initially widely patent superficial temporal artery-middle cerebral artery (STA-MCA) bypass and an enlarged donor vessel is presented. Over 17 months, the STA became markedly stenotic. Serial angiography is correlated with autopsy histological findings showing severe atherosclerotic changes throughout the donor vessel. The potential causative factors, both medical and surgical, are discussed and the appropriate literature is reviewed. Parallels are drawn from the cardiac bypass experience. The bypass itself may have precipitated or accelerated intimal hyperplasia, which stenosed (and may have eventually occluded) the vessel. Is this phenomenon more frequent than we realize?

Surgical resection of a pineal tumor containing elements of germinoma and astrocytoma

A 15-year-old boy presented with hydrocephalus due to a pineal tumor presumed to be a germinoma. After a shunting procedure, gross total tumor resection was carried out via an occipital transtentorial approach. Histopathological examination of the tissue demonstrated that, in addition to the expected germinoma, the tumor also contained areas of astrocytoma and areas that, taken in isolation as in a needle biopsy, could have been diagnosed as pineocytoma. The diagnosis and therapy of a pineal tumor of mixed histological types such as this lesion would be seriously compromised by "conventional" empiric radiation and even a stereotactic needle biopsy may not have provided an adequate tissue sample.