Decision Regret Following the Choice of Surgery or Active Surveillance for Small, Low-Risk Papillary Thyroid Cancer: A Prospective Cohort Study

Background: It is important to understand cancer survivors' perceptions about their treatment decisions and quality of life. Methods: We performed a prospective observational cohort study of Canadian patients with small (<2 cm) low-risk papillary thyroid cancer (PTC) who were offered the choice of active surveillance (AS) or surgery (Clinicaltrials.gov NCT03271892). Participants completed a questionnaire one year after their treatment decision. The primary intention-to-treat analysis compared the mean decision regret scale total score between patients who chose AS or surgery. A secondary analysis examined one-year decision regret score according to treatment status. Secondary outcomes included quality of life, mood, fear of disease progression, and body image perception. We adjusted for age, sex, and follow-up duration in linear regression analyses. Results: The overall questionnaire response rate was 95.5% (191/200). The initial treatment choices of respondents were AS 79.1% (151/191) and surgery 20.9% (40/191). The mean age was 53 years (standard deviation [SD] 15 years) and 77% (147/191) were females. In the AS group, 7.3% (11/151) of patients crossed over to definitive treatment (two for disease progression) before the time of questionnaire completion. The mean level of decision regret did not differ significantly between patients who chose AS (mean 22.4, SD 13.9) or surgery (mean 20.9, SD 12.2) in crude (p = 0.730) or adjusted (p = 0.29) analyses. However, the adjusted level of decision regret was significantly higher in patients who initially chose AS and crossed over to surgery (beta coefficient 10.1 [confidence interval; CI 1.3-18.9], p = 0.02), compared with those remaining under AS. In secondary adjusted analyses, respondents who chose surgery reported that symptoms related to their cancer or its treatment interfered with life to a greater extent than those who chose AS (p = 0.02), but there were no significant group differences in the levels of depression, anxiety, fear of disease progression, or overall body image perception. Conclusions: In this study of patients with small, low-risk PTC, the mean level of decision regret pertaining to the initial disease management choice was relatively low after one year and it did not differ significantly for respondents who chose AS or surgery.

Gender Differences in Fears Related to Low-Risk Papillary Thyroid Cancer and Its Treatment

Importance

Fear is commonly experienced by individuals newly diagnosed with papillary thyroid cancer (PTC).

Objective

To explore the association between gender and fears of low-risk PTC disease progression, as well as its potential surgical treatment.

Design, Setting, and Participants

This single-center prospective cohort study was conducted at a tertiary care referral hospital in Toronto, Canada, and enrolled patients with untreated small low risk PTC (<2 cm in maximal diameter) that was confined to the thyroid. All patients had a surgical consultation. Study participants were enrolled between May 2016 and February 2021. Data analysis was performed from December 16, 2022, to May 8, 2023.

Exposures

Gender was self-reported by patients with low-risk PTC who were offered the choice of thyroidectomy or active surveillance. Baseline data were collected prior to the patient deciding on disease management.

Main Outcomes and Measures

Baseline patient questionnaires included the Fear of Progression-Short Form and Surgical Fear (referring to thyroidectomy) questionnaires. The fears of women and men were compared after adjustment for age. Decision-related variables, including Decision Self-Efficacy, and the ultimate treatment decisions were also compared between genders.

Results

The study included 153 women (mean [SD] age, 50.7 [15.0] years) and 47 men (mean [SD] age, 56.3 [13.8] years). There were no significant differences in primary tumor size, marital status, education, parental status, or employment status between the women and men. After adjustment for age, there was no significant difference observed in the level of fear of disease progression between men and women. However, women reported greater surgical fear compared with men. There was no meaningful difference observed between women and men with respect to decision self-efficacy or the ultimate treatment choice.

Conclusions and Relevance

In this cohort study of patients with low-risk PTC, women reported a higher level of surgical fear but not fear of the disease compared with men (after adjustment for age). Women and men were similarly confident and satisfied with their disease management choice. Furthermore, the decisions of women and men were generally not significantly different. The context of gender may contribute to the emotional experience of being diagnosed with thyroid cancer and its treatment perception.

Outcomes of Early Transition of Low-Risk Thyroid Cancer Patients from Specialist to Primary Care

BACKGROUND

Recently published clinical pathways for management of thyroid cancer outlined the criteria for transitioning low-risk patients to primary care within one to five years from diagnosis. However, discharge patterns among endocrinologists remain heterogeneous as there lacks a consensus regarding post-treatment care for thyroid cancer patients.

OBJECTIVE

This study described general characteristics and outcomes of thyroid cancer patients who were discharged from specialist care and transitioned to a primary care-based follow-up clinic.

METHODS

Thyroid cancer patients seen in the After Cancer Treatment Transition (ACTT) clinic at Women's College Hospital (Toronto, Canada) were included in the study. Electronic medical records were reviewed between May and October 2021 to collect patient characteristics and outcomes. Descriptive statistics were calculated.

RESULTS

The study cohort included 148 thyroid cancer patients and 76% were female. All cases were papillary thyroid cancer and most diagnoses were classified as T₂ (42%), N₀ (55%), M₀ (91%), and stage 1 (83%). Nearly all patients (n = 147) had complete thyroidectomy. Levels of thyroglobulin and thyroglobulin antibodies (TgAb) were low overall, with only 5% of the study cohort deemed TgAb positive. Mean levels of thyroid stimulating hormone (TSH) measured at 2 time points (1.37 mIU/L, 1.42 mIU/L) were within normal range. About 91% of the study cohort had normal TSH levels and 82% met target TSH levels. There were 2 cases of recurrence; however, investigation determined that they were not initially appropriate candidates for transition to primary care. Nearly 99% (n = 146) of patients had excellent response to therapy, showed no evidence of disease recurrence, and have not required re-referral to specialist care.

CONCLUSIONS

These findings may reassure specialists that low-risk, stable thyroid cancer patients can be safely transitioned to primary care for post-treatment follow-up.

Genetic susceptibility to hereditary non-medullary thyroid cancer

Non-medullary thyroid cancer (NMTC) is the most common type of thyroid cancer. With the increasing incidence of NMTC in recent years, the familial form of the disease has also become more common than previously reported, accounting for 5-15% of NMTC cases. Familial NMTC is further classified as non-syndromic and the less common syndromic FNMTC. Although syndromic NMTC has well-known genetic risk factors, the gene(s) responsible for the vast majority of non-syndromic FNMTC cases are yet to be identified. To date, several candidate genes have been identified as susceptibility genes in hereditary NMTC. This review summarizes genetic predisposition to non-medullary thyroid cancer and expands on the role of genetic variants in thyroid cancer tumorigenesis and the level of penetrance of NMTC-susceptibility genes.

A Quantitative Analysis Examining Patients' Choice of Active Surveillance or Surgery for Managing Low-Risk Papillary Thyroid Cancer

Background: It is important to understand patient preferences on managing low-risk papillary thyroid cancer (PTC). Methods: We prospectively followed patients with low-risk PTC <2 cm in maximal diameter, who were offered the choice of thyroidectomy or active surveillance (AS) at the University Health Network (UHN), in Toronto, Canada. The primary outcome was the frequency of AS choice (percentage with confidence interval [CI]). Univariate and multivariable analyses were performed to identify predictors of the choice of AS. Results: We enrolled 200 patients of median age 51 years (interquartile range 42-62). The primary tumor measured >1 cm in 55.5% (111/200) of participants. The AS was chosen by 77.5% [71.2-82.7%, 155/200] of participants. In a backwards conditional regression model, the clinical and demographic factors independently associated with choosing AS included: older age (compared with referent group <40 years)-age 40-64 years-odds ratio (OR) 2.78 [CI, 1.23-6.30, p = 0.014], age ≥65 years-OR 8.43 [2.13-33.37, p = 0.002], and education level of high school or lower-OR 4.41 [1.25-15.53, p = 0.021]; AS was inversely associated with the patient's surgeon of record being affiliated with the study hospital-OR 0.29 [0.11-0.76, p = 0.012]. In a separate backwards conditional logistic regression model examining associations with psychological characteristics, AS choice was independently associated with a fear of needing to take thyroid hormones after thyroidectomy-OR 1.24 [1.11-1.39, p < 0.001], but inversely associated with fear of PTC progression-OR 0.94 [0.90-0.98, p = 0.006] and an active coping mechanism ("doing something")-OR 0.43 [0.28-0.66, p < 0.001]. Conclusions: Approximately three-quarters of our participants chose AS over surgery. The factors associated with choosing AS included older age, lower education level, and having a surgeon outside the study institution. Patients' fears about either their PTC progressing or taking thyroid hormone replacement as well as the level of active coping style were associated with the decision. Our results inform the understanding of patients' decisions on managing low-risk PTC. Registration: Clinicaltrials.gov NCT03271892.

Weight-based thyroid dosing vs fixed dosing during pregnancy for subclinical hypothyroidism: A retrospective cohort study

OBJECTIVE

Thyroid hormones play a crucial role in foetal growth and neurocognitive development. Our aim was to compare a weight-based dosing method of starting thyroxine to a fixed-dose method in newly diagnosed women with subclinical hypothyroidism during pregnancy.

DESIGN

We performed a retrospective cohort study of consecutive women with newly diagnosed subclinical hypothyroidism during pregnancy seen at Mount Sinai Hospital and Women's College Hospital, Toronto, Canada 2015-2018.

PATIENTS

We identified women that were treated based on pre-pregnancy weight and those that were given a fixed dose of 50 mcg/day.

MEASUREMENTS

The percent of women who reached the target TSH of <2.5 mIU/L within 4-8 weeks was compared using a chi-squared test and a logistic regression model, adjusting for age, initial TSH and gestational age treatment was started.

RESULTS

393 women were included: 252 treated using a fixed-dose approach; 141 treated based on pre-pregnancy weight. In the unadjusted analysis, there was no difference between the groups in the percentage of women in the target range within 4-8 weeks (89.6% in the fixed-dose group vs 88.8% in the weight-based group (p = .954)). However, after adjustment for between-group differences in age, initial TSH and gestational age treatment was started, there was a significantly greater odds of achieving the target range using the weight-based dosing (OR 4.26 (1.60-11.7), p = .004).

CONCLUSIONS

Treating women with newly diagnosed subclinical hypothyroidism during pregnancy with a weight-based strategy increased the odds of reaching the target TSH range within 4-8 weeks. Clinicians caring for these women should consider this approach when starting treatment during pregnancy.

Endocrinologist-Perceived Factors Affecting the Transition of Thyroid Cancer Patients from Specialist to Primary Care Postcancer Treatment in Ontario, Canada

Background: Thyroid cancer patient discharge patterns from specialists are heterogeneous, with some specialists following patients for a longer period of time than others. With no well-established transitional plan, such as in breast and colorectal cancer, primary care physicians play a variable role in long-term thyroid cancer care. The objective of this study was to examine endocrinologist-perceived factors affecting the transition of care for thyroid cancer patients through a qualitative and quantitative survey of practicing endocrinologists in Ontario, Canada. Methods: All eligible practicing endocrinologists in Ontario were invited to participate in the study, via an email with an embedded survey link. Consent was assumed if the physician completed the survey. The survey collected physician demographics and asked a series of Likert-scale and open-ended questions on their views regarding transitioning care of their thyroid cancer patients. Quantitative analysis was based on mode and variability. Qualitative analysis was completed using inductive thematic analysis. Results: Seventy physicians completed the survey, with a response rate of 35.5%. Based on the responses to the Likert-scale questions, there was a lack of consensus in terms of discharging criteria for patients who had low-risk papillary thyroid cancer, stable thyrotropin levels, multiple nonthyroid-related comorbidities, and hemithyroidectomy with no disease recurrence. The majority of endocrinologists responded that the main factors affecting discharge included whether the primary care physician was able to follow their recommendations, whether the primary care physician could appropriately adjust levothyroxine doses, and whether the patient was confident that their primary care physician could manage their thyroid cancer follow-up. Themes extracted from the open-ended question also indicated that the main factors affecting the transition of care were related to the primary care physician, the patient, the imaging interpretation, and the discharge guidelines. Conclusion: The lack of consensus among endocrinologists affects the transition of patient care, and there is a need to provide clear and accurate information to primary care physicians and thyroid cancer patients on postcancer treatment care. Efforts should be sought to standardize discharge and long-term care.

Potential diabetes overtreatment and risk of adverse events among older adults in Ontario: a population-based study

AIMS/HYPOTHESIS

More than 25% of older adults (age ≥75 years) have diabetes and may be at risk of adverse events related to treatment. The aim of this study was to assess the prevalence of intensive glycaemic control in this group, potential overtreatment among older adults and the impact of overtreatment on the risk of serious events.

METHODS

We conducted a retrospective, population-based cohort study of community-dwelling older adults in Ontario using administrative data. Participants were ≥75 years of age with diagnosed diabetes treated with at least one anti-hyperglycaemic agent between 2014 and 2015. Individuals were categorised as having intensive or conservative glycaemic control (HbA_1c <53 mmol/mol [<7%] or 54-69 mmol/mol [7.1-8.5%], respectively), and as undergoing treatment with high-risk (i.e. insulin, sulfonylureas) or low-risk (other) agents. We measured the composite risk of emergency department visits, hospitalisations, or death within 30 days of reaching intensive glycaemic control with high-risk agents.

RESULTS

Among 108,620 older adults with diagnosed diabetes in Ontario, the mean (± SD) age was 80.6 (±4.5) years, 49.7% were female, and mean (± SD) diabetes duration was 13.7 (±6.3) years. Overall, 61% of individuals were treated to intensive glycaemic control and 21.6% were treated to intensive control using high-risk agents. Using inverse probability treatment weighting with propensity scores, intensive control with high-risk agents was associated with nearly 50% increased risk of the composite outcome compared with conservative glycaemic control with low-risk agents (RR 1.49, 95% CI 1.08, 2.05).

CONCLUSIONS/INTERPRETATION

Our findings underscore the need to re-evaluate glycaemic targets in older adults and to reconsider the use of anti-hyperglycaemic medications that may lead to hypoglycaemia, especially in setting of intensive glycaemic control.

A Prospective Mixed-Methods Study of Decision-Making on Surgery or Active Surveillance for Low-Risk Papillary Thyroid Cancer

Background: Active surveillance (AS) of small, low-risk papillary thyroid cancers (PTCs) is increasingly being considered. There is limited understanding of why individuals with low-risk PTC may choose AS over traditional surgical management. Methods: We present a mixed-methods analysis of a prospective observational real-life decision-making study regarding the choice of thyroidectomy or AS for management of localized, low-risk PTCs <2 cm in maximum diameter (NCT03271892). Patients were provided standardized medical information and were interviewed after making their decision (which dictated disease management). We evaluated patients' levels of decision-self efficacy (confidence in medical decision-making ability) at the time information was presented and their level of decision satisfaction after finalizing their decision (using standardized questionnaires). We asked patients to explain the reason for their choice and qualitatively analyzed the results. Results: We enrolled 74 women and 26 men of mean age 52.4 years, with a mean PTC size of 11.0 mm (interquartile range 9.0, 14.0 mm). Seventy-one patients (71.0% [95% confidence interval 60.9-79.4%]) chose AS over surgery. Ninety-four percent (94/100) of participants independently made their own disease management choice; the rest shared the decision with their physician. Participants had a high baseline level of decision self-efficacy (mean 94.3, standard deviation 9.6 on a 100-point scale). Almost all (98%, 98/100) participants reported high decision satisfaction. Factors reported by patients as influencing their decision included the following: perceived risk of thyroidectomy or the cancer, family considerations, treatment timing in the context of life circumstances, and trust in health care providers. Conclusions: In this Canadian study, ∼7 out of 10 patients with small, low-risk PTC, who were offered the choice of AS or surgery, chose AS. Personal perceptions about cancer or thyroidectomy, contextual factors, family considerations, and trust in health care providers strongly influenced patients' disease management choices.

Risk for Thyroid Cancer Recurrence Is Higher in Men Than in Women Independent of Disease Stage at Presentation

Background: Well-differentiated thyroid cancer (DTC) presents at a more advanced stage in men than in women, and the mortality in men is higher than that in women. However, it is not clear whether DTC recurrence is affected by sex independent of stage at presentation. The objective of the present study was to assess if male sex is an independent risk factor for recurrence of DTC. Methods: The Canadian Collaborative Network for Cancer of the Thyroid (CANNECT) is a collaborative registry to describe patterns of care for thyroid cancer. We included patients from the CANNECT registry with DTC diagnosed at age 18 or older between 2000 and 2010. We compared men and women with respect to presentation, management, and recurrence risk, stratified for American Joint Committee on Cancer (AJCC) stage. Results: We included 2595 patients, 2067 (79.7%) women and 528 (20.3%) men. Men presented with more advanced AJCC stage (p < 0.001), T stage (p < 0.001), N stage (p < 0.001), and M stage (p = 0.002) There was no difference in follow-up duration between women (7.7 ± 4.0 [mean ± standard deviation] years) and men (7.7 ± 4.0 years, p = 0.985). Overall recurrence was 2.2% (n = 46) for women and 8.5% (n = 45) for men (p < 0.001). In multivariate analysis adjusted for AJCC stage, men were at significantly greater risk for DTC recurrence than women (adjusted hazard ratio 2.72 [95% confidence interval [CI] 1.78-4.20]; p < 0.001). In multivariate analysis adjusted for tumor-node-metastasis (TNM) stage, men were at significantly greater risk for DTC recurrence than women (adjusted hazard ratio 2.31 [CI 1.48-3.60]; p < 0.001). Conclusions: Our study confirms that the risk for recurrence of DTC is higher in men than in women. Although men tend to present with more advanced-stage disease, the difference in recurrence risk persists when adjusted for stage of presentation. It needs to be determined whether sex should influence follow-up intensity and/or duration.

Type 2 Diabetes in Older Adults in Long-Term Care Homes: An Educational Intervention to Improve Diabetes Care

OBJECTIVES

Over 25% of nursing home residents have diabetes. Nurses (registered nurses and registered practical nurses), registered dietitians and personal support workers (PSWs) provide the bulk of diabetes care in long-term care (LTC) homes, but their self-rated diabetes knowledge is poor. In this study, we evaluated the impact of an educational intervention on comfort with, and knowledge of, diabetes management among frontline LTC staff.

METHODS

We implemented an educational intervention in 2 LTC homes in Ontario that targeted nurses and dietitians, PSWs and physicians. A self-assessment questionnaire and a knowledge test were administered to nurses and dietitians and PSWs before and after the intervention. We also measured pre- and postintervention glycated hemoglobin levels, use of sliding scale insulin and type and dose of diabetes medications prescribed.

RESULTS

After the intervention, both the nurses and dietitians and PSWs groups demonstrated increased comfort with diabetes management and improved self-appraised knowledge. Among PSWs, knowledge of foot care improved the most, and the nurses and dietitians group had the greatest improvement in knowledge of blood glucose monitoring. In addition, there was reduced use of sliding scale insulin, and in the number of residents requiring renal-based dose reductions of glucose-lowering medications. This intervention was innovative as it targeted different LTC health-care providers; it demonstrated the potential to increase LTC health-care providers' confidence in diabetes management. Future studies could assess the clinical benefits of an educational intervention on rates of hypoglycemia and improving A1C targets.

CONCLUSIONS

An educational intervention can improve knowledge and comfort of diabetes management of frontline LTC staff.

Cryptosporidium in humans and animals-a one health approach to prophylaxis

Cryptosporidium is a major cause of moderate-to-severe diarrhoea in humans worldwide, second only to rotavirus. Due to the wide host range and environmental persistence of this parasite, cryptosporidiosis can be zoonotic and associated with foodborne and waterborne outbreaks. Currently, 31 species are recognized as valid, and of these, Cryptosporidium hominis and Cryptosporidium parvum are responsible for the majority of infections in humans. The immune status of the host, both innate and adaptive immunity, has a major impact on the severity of the disease and its prognosis. Immunocompetent individuals typically experience self-limiting diarrhoea and transient gastroenteritis lasting up to 2 weeks and recover without treatment, suggesting an efficient host antiparasite immune response. Immunocompromised individuals can suffer from intractable diarrhoea, which can be fatal. Effective drug treatments and vaccines are not yet available. As a result of this, the close cooperation and interaction between veterinarians, health physicians, environmental managers and public health operators is essential to properly control this disease. This review focuses on a One Health approach to prophylaxis, including the importance of understanding transmission routes for zoonotic Cryptosporidium species, improved sanitation and better risk management, improved detection, diagnosis and treatment and the prospect of an effective anticryptosporidial vaccine.

A systematic review of randomized controlled trials for management of persistent post-treatment fatigue in thyroid cancer survivors

BACKGROUND

Fatigue that persists post-treatment is commonly reported by thyroid cancer (TC) survivors.

METHODS

A systematic review of published English language randomized controlled trials (RCTs) on interventions for management of persistent post-treatment fatigue in TC was conducted. This review excluded studies on short-term interventions used in preparation for radioactive iodine diagnostic scans or treatment. An electronic search was executed in six databases and supplemented by a hand search. Two reviewers independently reviewed all citations from the electronic search and relevant full-text studies. Two abstractors independently critically appraised included studies and abstracted the data. The data were qualitatively summarized.

RESULTS

A total of 1086 unique citations and 25 full-text studies were reviewed. Four studies summarizing the results of three RCTs were included. The interventions included: combination triiodothyronine with levothyroxine (L-T4) therapy compared to L-T4 alone (one RCT), reduction in degree of thyrotropin (TSH) suppression using L-T4 compared to maintenance of TSH suppression (one RCT), and supervised exercise compared to inactivity (two RCTs examining different fatigue outcomes in same population). Trial duration ranged from 10 weeks to six months. All trials had limitations, and the number of TC survivors included in respective RCTs ranged from 15 to 36. Hormonal treatment RCTs had mixed fatigue outcome results within respective trials. However, multiple measures suggesting improvement in fatigue were reported following the exercise intervention.

CONCLUSIONS

There is paucity of RCTs to guide evidence-based management of persistent post-treatment fatigue in TC survivors. RCTs of interventions for prevention or treatment of fatigue in TC survivors are needed.

Persistent posttreatment fatigue in thyroid cancer survivors: a scoping review

The relevance of persistent posttreatment fatigue (PPF) to thyroid cancer (TC) survivor populations is not known. This article presents a scoping review, which is an overview of published research activity. Uncontrolled data suggest that PPF is one of the most common complaints in TC survivors. Furthermore, statistically significantly worse levels of fatigue were reported in TC survivors, compared with the general population or healthy controls. There was some inconsistency among PPF risk factors. More research is needed on PPF in TC survivors, including long-term prospective cohort studies, research on fatigue severity prevalence, and randomized controlled trials of treatment strategies.

Zeta potential vs apoptotic marker: which is more suitable for ICSI sperm selection?

PURPOSE

Selection of appropriate sperm is considered as a decision making point in the ICSI procedure. Canonically, sperm selection is based on morphology and motility. Recent advances in this field, have shown that, this procedure can be assisted by further selection based on membrane surface charge (Zeta potential) and surface apoptotic marker (phosphatidylserine externalization) using magnetic activated cell sorter (MACS). Based on the literature, both these procedures improve quality of selected sperm population. Therefore, this study aims to compare the efficiency of these two procedures.

METHODS

Semen samples were collected from 36 fertile and infertile (teratozoospermic and /or asthenozoospermic) individuals. Sperm DNA fragmentation, protamine deficiency and morphology were assessed by TUNEL, CMA3 and papanicolaou staining in unprocessed, MACS and Zeta processed samples.

RESULTS

Although both MACS and Zeta were able to separate a higher percentage of sperm with normal morphology, and lower DNA fragmentation and protamine deficiency compared to unprocessed, MACS procedure could significantly isolate, a greater percentage of sperm with normal acrosome and protamine content compared to Zeta procedure.

CONCLUSION

Both MACS and Zeta procedures improve the quality of the selected spermatozoa for ICSI. However, MACS procedure is more efficient in individuals with severe male factor infertility to select sperm with normal acrosome and protamine content but concern regarding transfer of MACS beads into the oocyte remains to be resolved.

Randomized Controlled Trial of a Computerized Decision Aid on Adjuvant Radioactive Iodine Treatment for Patients With Early-Stage Papillary Thyroid Cancer

Purpose

Decision-making on adjuvant radioactive iodine (RAI) treatment for early-stage papillary thyroid cancer (PTC) is complex because of uncertainties in medical evidence. Using a parallel, two-arm, randomized, controlled trial design, we examined the impact of a patient-directed computerized decision aid (DA) on the medical knowledge and decisional conflict in patients with early-stage PTC considering the choice of being treated with adjuvant RAI or not. The DA describes the rationale, possible risks and benefits, and the medical evidence uncertainty relating to the choice.

Patients and Methods

We recruited 74 patients with early-stage PTC after thyroidectomy. Participants were assigned by using 1:1 central computerized randomization to either the DA group with usual care (intervention) or usual care alone (control). Medical knowledge about PTC and RAI treatment (the primary outcome), as well as decisional conflict (a secondary outcome), were measured by using validated questionnaires, and the respective scores were compared between groups.

Results

Consistent with PTC epidemiology, 83.8% (62 of 74) of the participants were women, and the mean age was 45.8 years (range, 19 to 79 years). Medical knowledge about PTC and RAI treatment was significantly greater and decisional conflict was significantly reduced in the DA group compared with the control group (respective P values < .001). The use of adjuvant RAI treatment was not significantly different between groups (DA group, 11 of 37 [29.7%]; controls, seven of 37 [18.9%]; P = .278).

Conclusion

A computerized DA improves informed decision making in patients with early-stage PTC who are considering adjuvant RAI treatment. DAs are useful for patients facing decisions subject to medical evidence uncertainty.

Technical aspects and results of the transhiatal resection in adenocarcinomas of the gastroesophageal junction

The distribution of lymph node metastases of adenocarcinomas of the gastroesophageal junction is classified into three types. The R0 resection with complete lymphadenectomy therefore requires different resection methods for type 1 and type 2/3 tumors. Comparing the subtotal esophagectomy and the extended gastrectomy, no advantage in survival can be seen for one method or one tumor type (type 1 or type 2/3). The same is true for the lethality. Indeed, the transhiatal resection is accompanied by a higher complication rate. However, the different operation methods for cardiacarcinomas, with subtotal esophagectomy in type 1 and extended gastrectomy in type 2/3 tumors, should be maintained because of increased rates of local recurrence that may be expected if all cardiacarcinoma types were treated using subtotal esophagectomy with gastric tube interposition. Therefore, we suggest a subtotal esophagectomy only in type 1 tumors. In type 2/3 tumors, an extended gastrectomy with resection of the distal esophagus, lymphadenectomy of the lower mediastinum, and D2 lymphadenectomy should be performed.

Distinct clonal composition of primary and metastatic adrencorticotrophic hormone-producing pituitary carcinoma

The pathogenetic mechanisms underlying pituitary tumorigenesis are largely unknown. Previous reports have suggested that aggressive pituitary adenomas and/or carcinomas may be associated with genetic alterations that are distinct from those responsible for the more common and less aggressive pituitary adenomas. Here, we describe the clonal composition of a pituitary carcinoma, its recurrence and its metastasis. The samples studied were from a 48-year-old woman who presented with recurrent Cushing's syndrome. During the 8-year course of her disease, she had an ACTH-producing pituitary carcinoma requiring two transsphenoidal procedures and resection of a metastatic cervical lymph node. Her disease remained active despite surgical resection, external beam irradiation and medical treatment with ketoconazole. Ultimately, bilateral adrenalectomy was performed to control the hypercortisolism. Morphological and immunohistochemical studies revealed that the primary and recurrent pituitary tumours and the metastatic lesion were an endocrine tumour with ACTH and growth hormone immunoreactivity. Primary, recurrent and metastatic tumour DNAs were analysed for X-chromosome inactivation and loss of heterozygosity (LOH) at several microsatellite loci on chromosomes 9,10, 11, 13 and 22. All three lesions were monoclonal in composition as suggested by the pattern of X chromosome inactivation of the PGK-1 allele. Moreover, the primary, recurrent and metastatic lesions demonstrated LOH at the microsatellite allelic markers PYGM and D10S217. In contrast, however, the metastatic lesion showed a loss-to-retention pattern at two distinct loci (IFNA and D22S156) compared to the primary and recurrent pituitary tumours. These findings, while consistent with a clonal composition of the primary and metastatic pituitary lesions, show each clone to be distinct. This is the first description of a metastatic pituitary carcinoma with a distinct clonal composition from its primary source.

Absence of heart rate increase during inferoposterior left ventricular hypoperfusion caused by dipyridamole infusion

BACKGROUND

Stimuli such as inferoposterior myocardial infarction and right coronary injection with radiographic contrast media evoke a vasodepressor reflex characterized by bradycardia and hypotension (Bezold-Jarisch reflex). Dipyridamole acts by adenosine-mediated coronary vasodilation to disclose myocardial perfusion heterogeneity for thallium-201 scintigraphy.

OBJECTIVE

To determine whether there is a relationship between the site of left ventricular hypoperfusion and the heart rate response to dipyridamole.

DESIGN

One thousand eight hundred consecutive dipyridamole-thallium studies performed between 1985 and 1993 were reviewed to identify 48 subjects who met prespecified selection criteria.

SETTING

Nuclear cardiology laboratory of a university teaching hospital.

PATIENTS

Group 1 (n=26) had less than 5% pretest likelihood of coronary artery disease and normal thallium perfusion, group 2 (n=10) had isolated, completely reversible anterior perfusion abnormalities, and group 3 (n=12) had analogous inferoposterior perfusion abnormalities.

INTERVENTIONS

Heart rate and blood pressure were recorded at baseline and each minute of supine dipyridamole infusion.

MAIN RESULTS

After 4 mins of dipyridamole infusion, a significant increase in heart rate was observed in group 1 (+12 beats/min, P<0.05) and group 2 subjects (+12 beats/min, P<0.05) but not in group 3 subjects (+3 beats/min, not significant; P=0.016 compared with responses in the other two groups). Blood pressure was not affected by dipyridamole infusion in any group.

CONCLUSIONS

Isolated, moderate or severe inferoposterior hypoperfusion in response to dipyridamole is not accompanied by an increase in heart rate, suggesting that the chronotropic response to dipyridamole is modulated by the presence and location of myocardial perfusion abnormalities. This observation is consistent with the concept that inhibition of adenosine reuptake by dipyridamole, leading to local increases of adenosine concentration, exerts direct and/or reflex effects on heart rate that are site specific. The absence of a rise in heart rate during dipyridamole infusion may be a marker of impaired coronary flow reserve in the inferoposterior left ventricular wall.

Successful treatment of chloral hydrate cardiac toxicity with propranolol

A case of chloral hydrate overdose causing resistant ventricular arrhythmias is presented. Our case and other case reports suggest that chloral hydrate-induced arrhythmias are resistant to standard antiarrhythmic agents and that intravenous beta blockers should be the firstline treatment for these arrhythmias.