Malignancy rate in thyroid nodules classified as Bethesda category III (AUS/FLUS)

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology is the standard for interpreting fine needle aspiration (FNA) specimens. The "atypia of undetermined significance/follicular lesion of undetermined significance" (AUS/FLUS) category, known as Bethesda Category III, has been ascribed a malignancy risk of 5-15%, but the probability of malignancy in AUS/FLUS specimens remains unclear. Our objective was to determine the risk of malignancy in thyroid FNAs categorized as AUS/FLUS at a comprehensive cancer center.

METHODS

The management of 541 AUS/FLUS thyroid nodule patients treated at Memorial Sloan-Kettering Cancer Center between 2008 and 2011 was analyzed. Clinical and radiologic features were examined as predictors for surgery. Target AUS/FLUS nodules were correlated with surgical pathology.

RESULTS

Of patients with an FNA initially categorized as AUS/FLUS, 64.7% (350/541) underwent immediate surgery, 17.7% (96/541) had repeat FNA, and 17.6% (95/541) were observed. Repeat FNA cytology was unsatisfactory in 5.2% (5/96), benign in 42.7% (41/96), AUS/FLUS in 38.5% (37/96), suspicious for follicular neoplasm in 5.2% (5/96), suspicious for malignancy in 4.2% (4/96), and malignant in 4.2% (4/96). Of nodules with two consecutive AUS/FLUS diagnoses that were resected, 26.3% (5/19) were malignant. Among all index AUS/FLUS nodules (triaged to surgery, repeat FNA, or observation), malignancy was confirmed on surgical pathology in 26.6% [CI 22.4-31.3]. Among AUS/FLUS nodules triaged to surgery, the malignancy rate was 37.8% [CI 33.1-42.8]. Incidental cancers were found in 22.3% of patients. On univariate logistic regression analysis, factors associated with triage to surgery were younger patient age (p<0.0001), increasing nodule size (p<0.0001), and nodule hypervascularity (p=0.032).

CONCLUSIONS

In patients presenting to a comprehensive cancer center, malignancy rates in nodules with AUS/FLUS cytology are higher than previously estimated, with 26.6-37.8% of AUS/FLUS nodules harboring cancer. These data imply that Bethesda Category III nodules in some practice settings may have a higher risk of malignancy than traditionally believed, and that guidelines recommending repeat FNA or observation merit reconsideration.

A 21-year-old woman with consumptive hypothyroidism due to a vascular tumor expressing type 3 iodothyronine deiodinase

We present a 21-yr-old female with a large hepatic vascular tumor and subclinical hypothyroidism. A high level of the thyroid hormone inactivating enzyme type 3 iodothyronine deiodinase (D3) was detected in her tumor, and the TSH of 26.2 mU/liter returned to normal after surgical resection of the mass. This indicates that the vascular tumor caused this adult's hypothyroidism as has now been documented in nine infants with this syndrome. This first example of consumptive hypothyroidism in an adult indicates that the inactivation rate of thyroid hormone by D3 in a vascular tumor can stress the secretory capacity even of the TSH-stimulated normal adult thyroid gland.

Sonographic imaging of thyroid nodules and cervical lymph nodes

The initial application of sonography for the evaluation of the neck, more than 30 years ago, was to differentiate cystic and solid thyroid nodules. With improvements in technology, ultrasound has been applied to characterize distinct features in the appearance of thyroid nodules. More recently, its function has been expanded to assess cervical lymph nodes for metastatic thyroid cancer. This article discusses the sonographic features of thyroid nodules associated with malignancy and the role of ultrasound in the management of patients with thyroid cancer.

The effectiveness of two oral contraceptives in suppressing plasma androstenedione, testosterone, LH, and FSH, and in stimulating plasma testosterone-binding capacity in hirsute women

The effectiveness of two oral contraceptives in suppressing plasma androstenedione (A), testosterone (T), LH, and FSH and in stimulating testosterone-estradiol-binding globulin (TeBG) was evaluated in 39 hirsute women. Twenty-seven hirsute women received norethindrone 2 mg.-mestranol 0.1 mg. (Group I) and 12 received norgestrel 0.5 mg.-ethinyl estradiol 0.05 mg. (Group II). Hormone assays were performed before treatment and at the end of 3 weeks of therapy. Ninety percent of the women in both groups had an elevated plasma A and/or T. During treatment, plasma A,T, LH, and FSH were significantly reduced in both groups (p less than 0.01). In Group I, 78% of the women had a normal plasma A and T during treatment. In Group II, 83% of the women had a normal A and T during treatment. There was a greater increase in TeBG in Group I (p less than 0.01). It is concluded that these two oral contraceptives effectively suppressed the hyperandrogenism of most of the hirsute women.

SERIAL NECK ULTRASOUND IS MORE LIKELY TO IDENTIFY FALSE-POSITIVE ABNORMALITIES THAN CLINICALLY SIGNIFICANT DISEASE IN LOW-RISK PAPILLARY THYROID CANCER PATIENTS

OBJECTIVE

American Thyroid Association (ATA) low-risk papillary thyroid cancer (PTC) patients without structural evidence of disease on initial posttreatment evaluation have a low risk of recurrence. Despite this, most patients undergo frequent surveillance neck ultrasound (US). The objective of the study was to evaluate the clinical utility of routine neck US in ATA low-risk PTC patients with no structural evidence of disease after their initial thyroid surgery.

METHODS

We performed a retrospective review of 171 ATA low-risk PTC patients after total thyroidectomy, with or without radioactive iodine (RAI) ablation, who had a neck US without suspicious findings after therapy. The main outcome measure was a comparison of the frequency of finding false-positive US abnormalities and the frequency of identifying structural disease recurrence.

RESULTS

Over a median follow-up of 8 years, 171 patients underwent a median of 5 neck US (range 2-17). Structural recurrence with low-volume disease (≤1 cm) was identified in 1.2% (2/171) of patients at a median of 2.8 years (range 1.6-4.1 years) after their initial diagnosis. Recurrence was associated with rising serum thyroglobulin (Tg) level in 1 of the 2 patients and was detected without signs of biochemical recurrence in the other patient. Conversely, false-positive US abnormalities were identified in 67% (114/171) of patients after therapy, leading to additional testing without identifying clinically significant disease.

CONCLUSION

In ATA low-risk patients without structural evidence of disease on initial surveillance evaluation, routine screening US is substantially more likely to identify false-positive results than clinically significant structural disease recurrence.

The lecithin/sphingomyelin ratio in cases associated with fetomaternal disease

The efficacy of correlating the L/S ratio in the amniotic fluid with fetal lung maturity has been substantiated in normal pregnancies. In gestations complicated by fetomaternal diseases, however, the assay is less reliable. This study involves 555 pregnancies in which there was a significant maternal, fetal, or placental disorder. The L/S ratio was related to fetal respiratory maturity as measured by Dubowitz criteria and the occurrence of RDS. The results show that pre-eclampsia, chronic hypertension, diabetes (Class D, E, F), significant cardiovascular disease, severe hemoglobinopathies, various congenital anomalies, chronic placental insufficiency, and prolonged ruptured membranes accelerated the L/S ration. Conversely, mild diabetes (Class B, C), intrinsic renal disease, hepatitis, collagen disease, hydrops fetalis, syphilis, and toxoplasmosis were associated with a delay in the L/S ratio. A significant increase in erroneous responses was noted in these patients when the L/S ratio was correlated to infant maturity and to the incidence of RDS. Possible mechanisms for these findings are discussed.

Metabolites of meperidine in the fetal and maternal serum

Although meperidine appears to be the safest obstetric analgesic agent, it has been associated with infant respiratory depression in certain situations. It would appear that the incidence of fetal depression related to meperidine is dependent on the time of injection prior to delivery, the quantity of drug administered, and the rate of maternal metabolism of the analgesic. Previous work showed that meperidine is metabolized in the maternal system by one of three patterns. The present study demonstrates that the particular maternal serum pattern is characteristic for the individual, regardless of whether the patient is pregnant or not, and that the fetal depression, although usually mild, can be correlated with fetal pH data as well as Apgar scores. In addition, this study supports indirectly the contention that metabolites of meperidine rather than the parent compound cause fetal depression. It would appear, therefore, that in certain obstetric cases with a higher probability for infant depression, other analgesic agents might be considered, especially if the serum pattern indicates meperidine is being metabolized.

Frequent screening with serial neck ultrasound is more likely to identify false-positive abnormalities than clinically significant disease in the surveillance of intermediate risk papillary thyroid cancer patients without suspicious findings on follow-up ultrasound evaluation

CONTEXT

American Thyroid Association (ATA) intermediate-risk thyroid cancer patients who achieve an excellent treatment response demonstrate a low risk of structural disease recurrence. Despite this fact, most patients undergo frequent surveillance neck ultrasound (US) during follow-up.

OBJECTIVE

The objective of the study was to evaluate the clinical utility of routine screening neck US in ATA intermediate-risk patients documented to have a nonstimulated thyroglobulin less than 1.0 ng/mL and a neck US without suspicious findings after therapy.

PATIENTS AND DESIGN

Retrospective review of 90 ATA intermediate-risk papillary thyroid carcinoma patients treated with total thyroidectomy and radioactive iodine ablation in a tertiary referral center.

MAIN OUTCOME MEASURES

A comparison between the frequency of finding false-positive US abnormalities and the frequency of identifying structural disease recurrence in the study cohort was measured.

RESULTS

Over a median of 10 years, 90 patients had a median of six US (range 2-16). Structural disease recurrence was identified in 10% (9 of 90) at a median of 6.3 years. Recurrence was associated with other clinical indicators of disease in 5 of the 90 patients (5.6%, 5 of 90) and was detected without other signs of recurrence in four patients (4.8%, 4 of 84). False-positive US abnormalities were identified in 57% (51 of 90), leading to additional testing, which failed to identify clinically significant disease.

CONCLUSIONS

In ATA intermediate-risk patients who have a nonstimulated thyroglobulin less than 1.0 ng/mL and a neck US without suspicious findings after therapy, frequent US screening during follow-up is more likely to identify false-positive abnormalities than clinically significant structural disease recurrence.

Structure-activity studies of tylosin-related macrolides

The effects of tylosin-related macrolide antibiotics were examined in cell-free protein synthesis (using a coupled transcription-translation system derived from Streptomyces lividans) and against whole cells of that organism. Anti-ribosomal potency was determined primarily by the number and nature of the glycosyl substituents, and was not significantly influenced by lactone ring oxidation or sugar methylation. In contrast, uptake of the drugs into S. lividans was influenced, either positively or negatively, by each of these structural parameters. The presence of erm type I or erm type II resistance genes in S. lividans markedly affected the resistance phenotype and studies involving ribosomes from such strains revealed differences in macrolide activity that were not otherwise apparent.

Features of Turner's syndrome in women with polycystic ovaries

Four women with phenotypic features of Turner's syndrome and with poly cystic ovaries (PCO) are describe. In addition to the phenotypic features, Case 1 had primary amenorrhea and small PCO, Case 2 had a 46, XX/45, X karyotype (lumphocytes), Case 3 had enlarged PCO which contained a decreased number of oocytes, and Case 4 had enlarged PCO and was short in statute. These cases support the concept of a relation between PCO and the X chromosome. Some PCO may represent an intermediate condition in a spectrum that extends from the streak gonad of Turners syndrome to the normal ovary. Evidience for X chromosome involvement in PCO is summarized. The concept is advanced that at least some cases of OCO may be due to X chromosomal factors causing an abnormal follicular appartus.

Use of the afirma® gene expression classifier for preoperative identification of benign thyroid nodules with indeterminate fine needle aspiration cytopathology

Ruling out malignancy in thyroid nodules historically depended on thyroid resection and histopathological evaluation until fine needle aspiration (FNA) biopsy was introduced into the United States in the 1970's. Thyroid FNA biopsy identified a majority of thyroid nodules as benign, obviating the need for surgery in over half of the patients. However, 15%-30% of thyroid FNAs have indeterminate cytology that still requires operation, even though most of these operated nodules prove to be benign post-operatively. In order to predict which cytologically indeterminate thyroid nodules are benign and to potentially avoid surgery on these nodules, a recently described commercially available Gene Expression Classifier (GEC) test (Afirma®, Veracyte, Inc., South San Francisco, CA) has been developed that can be run on the FNA sample. This paper reviews the published literature and technology assessments/guidelines by independent parties and professional groups regarding the clinical utility as well as the analytic and clinical validity of the Afirma GEC.

Puerperal Weck clip sterilization: study I (first study of two consecutive studies)

One hundred and four puerperal applications have been performed using the (original) Weck pistol-grip applicator and applying the large Weck clip in the inverted V configuration. Follow-up varied from 37 to 42 months. The corrected failure rate was 8.7%. Mechanical difficulties were encountered with the jaws and metal sleeve of the (original) Weck pistol-grip applicator. Recovered clip configuration and tubal tissue histology are presented. Histologic changes suggest possible reversibility.

Novel plasmids from alkaliphilic halomonads

Seventeen alkaliphilic halomonads were examined for the presence of plasmids. Of these, eight strains harbored one or more from 5.3 to 33 kb in size, the first plasmids to be identified from an alkaliphilic halomonad source. Restriction and hybridization analysis revealed three strains that maintained an identical 5.9-kb plasmid which we named pAH1, two that had an identical 33-kb plasmid, and three others, of which one carried two plasmids of 5.3 and 15 kb, the former being designated pAH2. The two final strains maintained plasmids of 15 and 20.5 kb. Restriction mapping of both pAH1 and pAH2 indicated that they have a number of unique restriction sites and are of a small enough size to make them suitable for vector construction.