Faculty Bibliography

OBJECTIVES/OBJECTIVE:We evaluated the efficacy of the application of selective neck dissection to cases of clinically node-positive disease. METHODS:We performed a retrospective review at the University of Pittsburgh Head and Neck Cancer Database. A database of 65 patients was followed for an average of 36 months (range, 2 to 128 months) after they underwent selective neck dissection for clinically node-positive regional disease. RESULTS:Regional failure occurred in 8 patients (12.3%). In-field failure was experienced in 4 patients (6.1%), and failures outside the field of dissection occurred in 4 patients (6.1%). The overall incidence of extracapsular spread was 33.8% (22 of 65). Only 2 of 8 regional recurrences were associated with extracapsular spread at the initial neck dissection; however, both recurrences were in the contralateral, undissected side of the neck. Four regional failures were salvaged with surgery, with eventual overall regional control in the neck of 93.9%. Only 1 of 4 ipsilateral recurrences (25%) was successfully salvaged. In contrast, 3 of 4 contralateral failures (75%) were successfully salvaged. In our study population, 21 of 65 cases (32%) that were initially staged as clinically node-positive had no evidence of nodal metastases on pathologic examination. CONCLUSIONS:The application of selective neck dissection and postoperative irradiation in patients with clinically Nl and limited N2 clinical disease appears to be oncologically efficacious. Clinical overstaging occurred frequently in this sample, and may put patients at risk for more morbid surgical procedures.

BACKGROUND:Metastatic adenocarcinoma of the colon is a frequently encountered medical situation. Metastasis to the mandible from adenocarcinoma of the colon is very unusual and rarely reported. We report the case of a 73-year-old man with metastatic adenocarcinoma to the mandible. METHODS:The patient was referred for evaluation of a mass of 2 months' duration in the right parotid gland. He gave a history of watery bowel movements of unknown duration. Physical examination revealed a 7- x 6-cm hard mass, which seemed to be fixed to the right mandible. A CT scan revealed a destructive process involving the ramus and condyle of the right mandible that invaded the pterygopalatine fossa, pterygoid muscles, and middle cranial fossa. CT scans of the abdomen and pelvis revealed a 5-cm mass in the sigmoid colon with metastases to the liver. RESULTS:A biopsy of the mass in the mandible was performed, and metastatic adenocarcinoma of colonic origin was diagnosed. Colonoscopy and biopsy of the colonic mass substantiated that the sigmoid colon was the primary site of the cancer. Because the patient had disseminated disease, he declined treatment, and he died shortly thereafter. CONCLUSIONS:Although rare, metastatic adenocarcinoma from the colon to the mandible and parotid area should be included in the differential diagnosis of masses in this area. After analysis of our case and a review of the literature, we conclude that metastasis from adenocarcinoma of the colon is quite rare and represents incurable disseminated disease.

OBJECTIVE/HYPOTHESIS/OBJECTIVE:The utility of elective neck dissection in the management of patients with oral cavity and oropharyngeal cancer who present without neck metastases remains controversial. The study addressed the question of whether elective neck dissection improves regional control and survival in patients with squamous cell carcinoma of the oral cavity and oropharynx presenting with T1/T2 node-negative disease. STUDY DESIGN/METHODS:A nonrandomized, uncontrolled retrospective chart review. METHODS:A nonrandomized, uncontrolled retrospective chart review was performed. Resection of the primary tumor was performed in all patients. The neck was observed in one group, and elective neck dissection was performed for patients in another group. RESULTS:The study data indicated that elective neck dissection significantly improves regional control and regional recurrence-free survival. Elective neck dissection when compared with observation of the neck did not improve overall survival. CONCLUSION/CONCLUSIONS:Elective neck dissection reduces regional recurrence and may extend disease-free survival.

Objective To assess the correlation between changes in spin-lattice relaxation in the rotating frame (T(1rho)) and proteoglycan (PG) loss from bovine articular cartilage and to demonstrate the feasibility of performing T(1rho) MR imaging on a 1.5T clinical scanner. Design MR relaxation times (T(1rho), T(2) and T(1)) were measured from excised cartilage plugs (N=3) before and after two sequential digestions with trypsin on a 2T whole-body magnet. Proteoglycan and collagen loss induced by the trypsin digestion was measured using standard biochemical techniques. The correlation between changes in relaxation times and PG loss were tested with regression analysis. T(1rho) MRI was also performed on a clinical 1.5T MRI system to determine whether the spatial distribution of PG loss could be detected. The MRI results were compared with histology sections of native and PG-depleted tissue. Results Increase in T(1rho) relaxation times correlated with PG loss (R(2)=0.81). T(1rho) measurements alone were indicative of PG loss (R(2)=0.8), the addition of T1 and T2 data into the statistical model did not improve the correlation substantially (R(2)=0.83). T(1rho)-weighted imaging demonstrated a hyperintense lamina at the articular surface of the digested tissue, which was subjected to trypsin digestion that correlated with a superficial zone of PG loss observed on histological sections. Conclusion The results of this study demonstrate that T(1rho) relaxation changes are correlated with PG loss in vitro. Furthermore, T(1rho) measurements alone can be used to indicate PG loss data. T(1rho) MRI may thus be developed into a useful adjunct to existing techniques for the evaluation of cartilage disease.

RATIONALE AND OBJECTIVES/OBJECTIVE:The goal of this study was to evaluate the utility of T1rho weighting in magnetic resonance imaging of murine brain tumors. MATERIALS AND METHODS/METHODS:S91 Cloudman melanoma was implanted in mouse brains (n = 4). A T2-weighted spin-echo (SE) and a T1rho-weighted fast SE-based sequence were performed on a 4-T clinical imager. T2 and T1rho maps were computed. The tumor-to-normal-tissue contrast was compared between T2-weighted, T1rho-weighted, proton-density-weighted, and pre- and postcontrast T1-weighted SE images. RESULTS:The tumor-tissue contrast of the T1rho-weighted images was similar to that of the T2-weighted images but less than that of the postcontrast T1-weighted images. The T1rho-weighted images provided better definition of tumor boundaries than T2-weighted images. At spin-locking powers of 0.5 and 1.5 kHz, the T1rho of the tumor was 64.0 msec +/- 0.46 and 68.65 msec +/- 0.59, respectively. There was no significant inter- or intra-animal variation in T1rho for tumor or normal brain cortex. CONCLUSION/CONCLUSIONS:T1rho-weighted imaging performed at low spin-lock strengths qualitatively depicted tumor borders better than proton-density or T2-weighted imaging and could be useful in treatment planning when combined with other imaging sequences.

A fast spin-echo sequence weighted with a time constant that defines the magnetic relaxation of spins under the influence of a radio-frequency field (T1(rho)) was used in six subjects to measure magnetic resonance (MR) relaxation times in the knee joint with a 1.5-T MR imager. A quantitative comparison of T2- and T1(rho)-weighted MR images was also performed. Substantial T1(rho) dispersion was demonstrated in human articular cartilage, but muscle did not demonstrate much dispersion. T1(rho)-weighted images depicted a chondral lesion with 25% better signal-difference-to-noise ratios than comparable T2-weighted images. This technique may depict cartilage and muscular abnormalities.

Magnetic relaxation has been used extensively to study and characterize biological tissues. In particular, spin-lattice relaxation in the rotating frame (T(1rho)) of water in protein solutions has been demonstrated to be sensitive to macromolecular weight and composition. However, the nature of the contribution from low frequency processes to water relaxation remains unclear. We have examined this problem by studying the water T(1rho) dispersion in peptide solutions ((14)N- and (15)N-labeled), glycosaminoglycan solutions, and samples of bovine articular cartilage before and after proteoglycan degradation. We find in model systems and tissue that hydrogen exchange from NH and OH groups to water dominates the low frequency water T(1rho) dispersion, in the context of the model used to interpret the relaxation data. Further, low frequency dispersion changes are correlated with loss of proteoglycan from the extra-cellular matrix of articular cartilage. This finding has significance for the noninvasive detection of matrix degradation.