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I D Hay

Publications and source records attributed to I D Hay.

119 records · Page 7Linked to original sources

Locally invasive papillary thyroid carcinoma: 1940-1990.

Well-differentiated thyroid carcinoma infrequently invades the upper aerodigestive tract. However, when invasion occurs, it is the source of significant morbidity. The most common structures invaded by thyroid carcinoma are the recurrent laryngeal nerves, larynx, pharynx, and esophagus. Invasion of these structures produces symptoms of airway insufficiency, dysphagia, and hemoptysis. This study was designed to define more clearly the significance of invasion of papillary thyroid carcinoma on survival. At the Mayo Clinic, 262 patients treated for invasive papillary thyroid carcinoma between 1940 and 1990 were retrospectively evaluated. In this group the sites of invasion were muscle 53%, trachea 37%, laryngeal nerve 47%, esophagus 21%, larynx 12%, and other sites 30%. Complete tumor removal was accomplished in 56% of cases. Kaplan-Meier survival curves were calculated for the population. The overall survival was 79% at 5 years, 63% at 10 years, and 54% at 15 years. When the Cox proportional hazard model was applied to the survival data, the factors that had significant influence on survival were invasion of the trachea and the esophagus. Completeness of resection approached statistical significance. Muscle invasion, laryngeal invasion, and recurrent laryngeal nerve invasion had no significant independent influence on survival. These data suggest that when papillary thyroid carcinoma extends beyond the thyroid capsule and invades adjacent structures, the site invaded will influence survival. Survival may be improved in those cases in which complete surgical excision of the tumor is performed.

Carcinoma, Papillary↗

Diagnostic and prognostic utility of flow cytometric DNA measurements in follicular thyroid tumors.

Distinguishing cellular follicular adenomas (FA) from minimally invasive follicular carcinomas (FC) continues to plague even experienced thyroid pathologists. DNA ploidy analysis has been promoted as a means of making this differentiation; however, the finding of DNA aneuploidy in FA has caused concern that they may demonstrate potential for malignant behavior or should even be reclassified as low-grade noninvasive cancers. In histologically-proven FC, nuclear DNA content has been claimed to have predictive power equivalent to that of all other prognostic factors combined. The aims of the present study, therefore, were to define the DNA ploidy characteristics of FA and FC, to assess the diagnostic potential of cell-cycle parameters, and, in FC, to investigate the prognostic role of such measurements. We measured DNA content of 124 tumors (60 FA, 64 FC). DNA pattern was normal (diploid) in 75% of FA and 45% of FC, tetraploid/polyploid (T/P) in 13% of FA and 25% of FC, and aneuploid in 12% of FA and 30% of FC. FC was histologically verified in 39% of DNA normal, 67% of T/P, and 73% of aneuploid tumors. DNA index, S-phase, G2M, and S-phase plus G2M were analyzed and were not helpful in differentiating between FA and FC. No patient with FA developed tumor recurrence. In FC (excluding the Hürthle cell variant), no significant differences were found among the 3 DNA ploidy groups with respect to either cancer death or tumor recurrence; however, combining the Hürthle cell variant of follicular carcinomas with pure follicular carcinomas, the presence of distant metastases, DNA aneuploidy, and patient age were the only independently significant prognostic variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

Expression of a potential metastasis suppressor gene (nm23) in thyroid neoplasms.

Identification of multiple clinical and pathologic prognostic factors in differentiated thyroid cancer has permitted some degree of risk stratification. However, these clinical indices fail to distinguish potential intrinsic differences in tumor virulence. The nm23 gene has been identified as a potential metastasis suppressor gene that is homologous to nucleoside diphosphate kinases. Studies in human breast cancer have shown a significant inverse correlation between nm23 levels and nodal involvement/tumor recurrence. Given the possible clinical utility of a marker of metastatic potential in the management of thyroid carcinoma, we examined 34 thyroid neoplasms and a human medullary thyroid cancer (MTC) cell line (TT) for nm23 expression. Normalized nm23 expression was assessed by Northern analysis of tumor RNA. nm23 Expression (tumor expression/TT cell expression, mean +/- SE) was 1.14 +/- 0.15* in MTCs (n = 5), 0.70 +/- 0.10* in follicular cancers (n = 6), 0.51 +/- 0.11 in papillary cancers (n = 19), and 0.31 +/- 0.03 in follicular adenomas (n = 4) (*p < 0.05 when compared to adenomas). Within histologic groups, we found no correlation between nm23 expression and nodal involvement of distant metastases. Our results indicate that thyroid neoplasms of different histologies express varying levels of the nm23 transcript. Although nm23 expression seems diminished in metastatic breast cancer, it appears not to be the case in metastatic thyroid cancer. The nm23 gene may therefore have different roles in the evolution and metastases of different neoplasms.

Adenocarcinoma, Follicular↗

Non-Hodgkin's lymphoma of the thyroid: is more than biopsy necessary?

Whereas excisional surgery and radiotherapy have resulted in a favorable outcome when non-Hodgkin's lymphoma of the thyroid (NHLT) is confined to the thyroid gland, controversy persists over the potential advantage of aggressive debulking in favor of diagnostic biopsy alone when disease cannot be completely resected. Our aims in this study were to delineate the present role of surgery in NHLT in pre-operative staging, the impact of the extent of resection on achieving complete remission and cause-specific survival, and patterns of failure. All 62 patients who underwent primary surgery for NHLT at the Mayo Clinic between 1965 and 1989 were analyzed. By postoperative staging, 50 patients were stage IE or IIE. Overall survival was 53% and 46% at 5 and 10 years; 80% for stage IE confined to the thyroid, 58% for stage IE-extrathyroid, 50% for stage IIE, and 36% for stages IIIE and IVE. Complete remission was achieved in 88% of patients who underwent diagnostic biopsy plus adjuvant therapy alone compared to 85% for patients in whom debulking plus adjuvant therapy was used. There was no difference in cause-specific survival in these two groups or in cause-specific survival in two subgroups who achieved complete remission. Relapse after complete remission occurred in 12 (26%) of 46 patients, only 2 of whom survived long-term after salvage therapy. The role of surgery in NHLT is diminishing and advances that will increase complete remission and relapse-free survival will not likely involve more aggressive surgical resections.

Adult↗

Hürthle cell (oxyphilic) papillary thyroid carcinoma: a variant with more aggressive biologic behavior.

The latest World Health Organization International Classification defines papillary thyroid carcinoma by its "follicular cell differentiation...as well as characteristic nuclear changes". However the oxyphilic (Hürthle cell) papillary carcinoma have nuclei which generally resemble the nuclei seen in oxyphilic follicular carcinomas, and such oxyphilic papillary tumors may behave more aggressively than typical papillary cancers. To further characterize these rare tumors, we identified during a 32-year period 22 patients with oxyphilic papillary cancer and compared them with 1,084 patients with typical papillary cancers and 57 patients with oxyphilic follicular cancers treated by the Mayo surgical group during the same time period. Although typical papillary and oxyphilic papillary cancers were comparable with regards to patient age, tumor size and extent, TNM stage, and prognostic score (AGES), there were significant differences. Compared to typical papillary tumors, oxyphilic papillary cancers had fewer neck nodal metastases at primary diagnosis (5% vs 40%, p less than 0.0001), were more often DNA non-diploid (71% vs 21%, p less than 0.001), and after 10 postoperative years had higher rates of both tumor recurrence (28% vs 11%, p less than 0.0001) and cause-specific mortality (1.7% vs 4%, p less than 0.0005). In these four important respects the oxyphilic papillary cancers more resembled the oxyphilic follicular cancers. For oxyphilic follicular cancers, the frequency of initial neck nodal metastases was 7% (cf 5%); 83% of the oxyphilic follicular tumors were non-diploid (cf 71%), and at 10 years postoperatively the tumor recurrence and cause-specific mortality rates were 28% and 18%, insignificantly different from 28% and 17% seen with the oxyphilic papillary cancers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Prognostic indicators in differentiated thyroid carcinoma.

BACKGROUND: Thyroid cancer ranges from well-differentiated lesions with an excellent prognosis to anaplastic carcinoma, which is almost uniformly fatal. Thus, methods to assess the behavior of thyroid malignancies are necessary to arrive at appropriate treatment decisions. METHODS: We discuss the factors that affect the prognosis of patients with well-differentiated thyroid malignancies, including papillary, follicular, Hürthle cell, and medullary thyroid carcinomas. We also review the presentation, therapy, and outcome of patients seen at our center over a span of 50 years. These data have identified those prognostic factors that are predictive of survival and recurrence in differentiated thyroid cancer. RESULTS: Several classifications with different variables have been developed to define risk-group categories. Three widely used systems, in addition to the TNM staging system, include AGES, AMES, and MACIS. CONCLUSIONS: A better understanding of independently important prognostic variables will result in improved patient care and treatment.

Carcinoma↗