Tumor shrinkage associated with whole-mount histopathologic techniques in oral tongue carcinoma.

Shrinkage artifact of tumor tissue from histologic processing has not been rigorously quantified, particularly where the entire tumor is represented in a whole-mount specimen. Fourteen patients underwent partial-glossectomy for oral tongue carcinoma (OTC). Specimens were embedded into agar, cut into 3 mm blocks and photographed (macroscopic image), prior to histopathologic processing. Histology slides were digitized. Contours were made of tumor on both image sets and area plotted against block position. Volume estimates were mathematically derived based on these plots. The tumors shrank in volume by 20.2% (p=0.0006) on average; shrinkage by area ranged for all image pairs 0-48%. Tumor volume>median was significant in absolute shrinkage (p=0.002) but not percent shrinkage (p=0.42). Age, gender, and T stage were independent of shrinkage. This data shows whole-mount techniques produce shrinkage artifact in OTC that varies between tumors and blocks in the same tumor. In order to account for shrinkage, measurement must be performed case-by-case.

Evaluation of microscopic disease in oral tongue cancer using whole-mount histopathologic techniques: implications for the management of head-and-neck cancers.

PURPOSE: To map the distribution of microscopic disease (MD) in head-and-neck cancer by analyzing digital images of whole-mounted serial sections of tongue cancer specimens. METHODS AND MATERIALS: Ten T1-3 oral tongue cancer specimens were evaluated. The specimens were sliced into 3-mm blocks from which one or more 4-µm slides were taken and digitized to create whole-mounted serial sections. Gross tumor and microscopic disease were digitally contoured on each slide. Lines perpendicular to the gross tumor volume (GTV) edge were created at 0.05-mm intervals and the distance between GTV and MD measured. RESULTS: Of 88 slides assessed, 44 (50%) had evidence of MD. Of the 63,809 perpendicular lines drawn along the GTV edges, 2320 (3.6%) encountered microscopic disease along their path. The majority of MD abutted the GTV, and only 26.7% was noncontiguous with the GTV edge. The maximum distance from the border was 7.8 mm. Ninety-nine percent of all MD was within 4.75 mm and 95% was within 3.95 mm of the GTV. CONCLUSION: In this study we were able to assess the distribution of MD more accurately than has been possible with routine pathologic techniques. The results indicate that when the GTV is correctly identified, there is very little MD to be found outside this volume. This has implications for the volume of tissue resected at surgery and the volume included in the clinical target volume in conformal radiotherapy planning.

Sleep apnea in patients with oral cavity and oropharyngeal cancer after surgery and chemoradiation therapy.

OBJECTIVE: To determine the point prevalence of sleep apnea in patients following oral and oropharyngeal cancer treatment at a major tertiary care referral center. STUDY DESIGN: A retrospective cross-sectional survey. SUBJECTS AND METHODS: Twenty-four patients with established oral or oropharyngeal cancer were submitted to overnight polysomnography. The surgical group consisted of 15 patients (11 male, 4 female; average age 64.2 yrs) having undergone primary surgery with radial forearm free flap reconstruction. The remaining patients (5 male, 4 female; average age 54.8 yrs) were treated nonsurgically with chemoradiation therapy. The fatigue-related daytime sleepiness was measured with the Epworth sleepiness scale (ESS). RESULTS: Eleven patients in the surgical group and three in the nonsurgical group had a respiratory disturbance index (RDI) greater than 15 (odds ratio = 5.5, P = 0.092). Twelve patients in the surgical group and five in the nonsurgical group had significant oxygen desaturation during sleep hours (odds ratio = 3.3, P = 0.356). There was no observed significant correlation between RDI and oxygen desaturation (r(2) = 0.28), nor was there any observed association between the RDI and ESS score (r(2) = 0.18). CONCLUSION: This preliminary study has suggested that surgical patients in our cohort have a higher prevalence of moderate to severe obstructive sleep apnea in the postoperative period, when tested, compared with a nonsurgical group. A small sample size and incomplete matching on important cofactors of interest, such as primary site location, body mass index, and thyroid function, limit this study. A pretreatment and post-treatment analysis is obviously required to demonstrate any significant level of association between treatment type and sleep apnea status.