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H Rubén Harach

Publications and source records attributed to H Rubén Harach.

9 recordsLinked to original sources
PubMed2004

Thyroid implants after surgery and blunt trauma.

The differential diagnosis of thyroid tissue found laterally in the neck includes several conditions: lymph node deposits of thyroid carcinoma, "benign metastatic thyroidosis," detached thyroid nodules, and true ectopic thyroid tissue. We have studied nine cases with thyroid deposits in the soft tissues of the neck that do not conform to these diagnoses. We present evidence that they represent surgical or traumatic implantation of thyroid neoplasms. Eight of the nine cases presented one to 26 years after initial surgery. Adequate information of the operative procedure was available in seven cases, one patient underwent subtotal lobectomy and six subtotal thyroidectomy for a nodular gland. The nodules occurred within the operation field with no evidence that they were within lymph nodes. In six cases, birefringent particles consistent with talc from the earlier operation were found adjacent to the nodules. Three cases showed implants of colloid nodules, three of follicular adenoma, one of oncocytic (Hürthle) cell adenoma and one of follicular carcinoma. In the ninth case, infiltrating thyroid tissue in muscle and fibrous tissue presented 3 years after major blunt trauma to the neck. The tissue resembled that in a disrupted thyroid nodule present in the gland itself and was regarded as traumatically implanted. The observation that surgery or trauma to a nodular thyroid can occasionally lead to multiple subcutaneous thyroid implants has implication for management of thyroid disease. Therapy may be difficult; recurrence followed surgical removal of the nodules in three cases, and radioiodine may be a more effective therapy. Recognition of this entity is important for accurate pathologic diagnosis. It is apparently limited to implantation of tumor. The absence of implantation of normal or hyperplastic thyroid, despite the high frequency of partial thyroidectomy in Graves' disease, has pathobiological implications. These findings also support the generally held view that lobectomy rather than nodulectomy is the operation of choice for a solitary nodule.

Adult↗
PubMed2002

Pathology of the autonomously functioning (hot) thyroid nodule.

We describe the pathologic findings of 73 clinically and scintigraphically confirmed hot nodules. In general, hot nodules from an unselected group primarily treated by surgery were smaller and the sex ratio was closer to equality compared with the ample female predominance in the referral, pre-, and post-prophylaxis groups. Malignancy was observed in six cases (8.2%) (5 follicular, 1 papillary). Of the 67 benign tumors, 48 (71.6%) were adenomas which showed the cytoarchitectural features of hot nodules described previously, and 19 (28.3%) were less well-differentiated adenomas that included a few oxyphil tumors. Intracolloid oxalate crystals from background thyroid tissue were present in 59 assessable cases (83%) overall, the majority showed more than occasional crystals that had a tendency to increase in number with decreasing morphologic activity of the thyroid epithelium. Thyroglobulin protein and mRNA stainings tended to be more pronounced in cell cytoplasm of the tumors than in background thyroid. This study shows that hot nodules may show a wide morphologic spectrum of follicular neoplasms and can be occasionally malignant. It is inferred from the morphologic and other findings that it is likely that some, if not all, of the primary follicular cancers associated with hyperfunction arise by clonal progression from benign hot nodules. This progression is rare, probably because most hot nodules present with the symptoms of hyperfunction and receive early treatment.

Adenoma↗
PubMed2002

Thyroid cancer and thyroiditis in Salta, Argentina: a 40-yr study in relation to iodine prophylaxis.

The natural history of thyroid cancer and thyroiditis in relation to iodine prophylaxis in the region of Salta, Argentina, where goiter is common was investigated over a time span of 40 yr. For analysis of thyroid cancer, the specimens were divided into two periods. The first 15 yr (59 cases), including 5 yr before prophylaxis, was compared with the second 25 yr (182 cases), a period well after salt iodination. Papillary carcinomas formed the largest group of tumors in both periods, with a significant increase in their proportion in the second period (44 vs 60%, chi(2): p < 0.05), while the percentage of follicular and undifferentiated carcinomas decreased and medullary carcinoma remained about the same. The ratio of papillary to follicular carcinoma rose from 1.7:1 in the first period to 3.1:1 in the second. Four thyroid lymphomas of non-Hodgkin's B-cell type occurred in the second period in females over age 50. A severe lymphoid thyroiditis was present in the two cases with assessable background thyroid tissue. The frequency of moderate to severe lymphoid infiltrate in females rose from 2 of 12 (16.6%) in the preprophylaxis period to 34 of 114 (28.0%) in the last 25 yr after prophylaxis. After salt prophylaxis, thyroiditis was more frequent in patients with papillary carcinoma (36.2%) than in those with nonpapillary tumors (14.7%) (chi(2), p < 0.02). These observations indicate that a high dietary intake of iodine may be associated with a high frequency of papillary carcinoma and thyroiditis, and that thyroiditis is more commonly associated with papillary carcinoma than with other thyroid tumors. The occurrence of non-Hodgkin's lymphomas only in the postprophylaxis period may be linked to an increase in thyroiditis.

Adult↗
PubMed2001

Familial nonmedullary thyroid neoplasia.

Thyroid carcinoma accounts for less than 1% of all human malignancies and carries one of the highest overall familial relative risks as compared with cancers from other sites. This is particularly true for medullary carcinoma, as well as for carcinomas of follicular cell origin in general, where inheritance has been implicated in 2.5 to 6.3% of the cases. Familial nonmedullary thyroid tumors show a variety of genetic mechanisms implicated in thyroid tumorigenesis and occur in several tumor-prone traits (e.g., familial adenomatous polyposis [FAP] and Cowden's disease [CD]) or as the only or dominant inherited manifestation. The latter group includes the most common familial papillary carcinoma, in which environmental factors such as radiation exposure may also play an important etiological role. Familial follicular cell tumors show a variety of morphological features ranging from benign thyroid nodulation to carcinoma, usually develop in young individuals, and tend to be multicentric--an indication for total thyroidectomy to avoid tumor recurrence and potential risk of malignant transformation. The pathologist may play an important role in the histological interpretation of familial nonmedullary thyroid tumors, which may lead to further clinicogenetical investigations of the affected patient and family screening. Familial follicular cell thyroid neoplasms show a complex molecular biological pathway of tumorigenesis when compared between themselves and with their sporadic counterparts.

Adenocarcinoma, Follicular↗
PubMedDate not supplied

Accuracy of aspiration cytology in thyroid cancer: a study in 1 institution.

OBJECTIVE: To evaluate sensitivity of fine needle aspiration cytology in diagnosing malignancy in histologically proven thyroid cancers. STUDY DESIGN: We analyzed the results of 335 smears from clinically significant and histologically proven primary thyroid cancers obtained from 9,115 aspirates, taking into account the pathologist's experience. RESULTS: The sensitivity for diagnosing thyroid malignancy in general was 88.0% (range, 82.6-97.2% from less to more experienced pathologist, respectively). It was higher for papillary (mean, 91.9%) and medullary (mean, 95.4%) carcinomas than for follicular cancer (mean, 50.0%). Biopsy showed thyroid cancer in 27.4% suspicious (range, 22.9-33.3%), 4.4% indeterminate (range, 1.9-6.6%) and 4.1% negative (range, 0-6.6%) smears. CONCLUSION: The more experienced the pathologist, the higher the sensitivity rate for recognizing thyroid cancer in general and by histologic type on aspirates despite some limitations of the method in identifying follicular carcinoma. We recommend thyroidectomy for patients with positive smears and follow-up for patients with benign, indeterminate and suspicious cytology, provided that the cytologic specimens were reviewed by an experienced pathologist.

Biopsy, Fine-Needle↗