The potential role of precision medicine to alleviate racial disparities in prostate, bladder and renal urological cancer care

Background

Racial disparities in oncological outcomes resulting from differences in social determinants of health (SDOH) and tumour biology are well described in prostate cancer (PCa) but similar inequities exist in bladder (BCa) and renal cancers (RCCs). Precision medicine (PM) aims to provide personalized treatment based on individual patient characteristics and has the potential to reduce these inequities in GU cancers.

Objective

This article aims to review the current evidence outlining racial disparities in GU cancers and explore studies demonstrating improved oncological outcomes when PM is applied to racially diverse patient populations.

Evidence acquisition

Evidence was obtained from Pubmed and Web of Science using keywords prostate, bladder and renal cancer, racial disparity and precision medicine. Because limited studies were found, preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were not applied but rather related articles were studied to explore existing debates, identify the current status and speculate on future applications.

Results

Evidence suggests addressing SDOH for PCa can reverse racial inequities in oncological outcomes but differences in incidence remain. Similar disparities in BCa and RCC are seen, and it would be reasonable to suggest achieving parity in SDOH for all races would do the same. Research applying a PM approach to different ethnicities is lacking although in African Americans (AAs) with metastatic castrate-resistant prostate cancer (mCRPCa) better outcomes have been shown with androgen receptor inhibitors, radium-223 and sipuleucel. Exploiting the abscopal effect with targeted radiation therapy (RT) and immunotherapy has promise but requires further study, as does defining actionable mutations in specific patient groups to tailor treatments as appropriate.

Conclusion

For all GU cancers, the historical underrepresentation of ethnic minorities in clinical trials still exists and there is an urgent need for recruitment strategies to address this. PM is a promising development with the potential to reduce inequities in GU cancers, however, both improved understanding of race-specific tumour biology, and enhanced recruitment of minority populations into clinical trials are required. Without this, the benefits of PM will be limited.

Risk-Tailoring Radiotherapy for Endometrial Cancer: A Narrative Review

Endometrial cancer is the most common gynecologic cancer in the United States and it contributes to the second most gynecologic cancer-related deaths. With upfront surgery, the specific characteristics of both the patient and tumor allow for risk-tailored treatment algorithms including adjuvant radiotherapy and systemic therapy. In this narrative review, we discuss the current radiation treatment paradigm for endometrial cancer with an emphasis on various radiotherapy modalities, techniques, and dosing regimens. We then elaborate on how to tailor radiotherapy treatment courses in combination with other cancer-directed treatments, including chemotherapy and immunotherapy. In conclusion, this review summarizes ongoing research that aims to further individualize radiotherapy regimens for individuals in an attempt to improve patient outcomes.

The effects of radiation therapy on the heart: implications for management

Chemotherapy, radiotherapy, and surgery constitute the three primary modalities employed in the treatment of patients with cancer. Radiotherapy, in particular, is a mainstay of treatment for patients with cancers of the breast, esophagus, lung, and lymph nodes. Prior studies have shown, however, that radiotherapy can impact the heart. Radiation exposure, in fact, can lead to pathophysiological changes that may result in short- and long-term radiation-induced cardiac toxicities. Such toxicities can cause substantial morbidity and may manifest clinically in the weeks to years after the completion of treatment. As a result, in both modern clinical practice and clinical trials, the heart has been recognized as an organ-at-risk, and radiotherapy treatment plans seek to minimize the dose that it receives. In this review, we focus on the impacts of radiotherapy on underlying cardiac risk factors, the pathophysiology of radiotherapy-induced cardiac changes, and the clinical impacts of radiotherapy on the heart. Due to the location of the heart, we focus primarily on patients who have received radiotherapy for cancers of the breast, esophagus, lung, and lymph nodes, and those who have received cardiac-directed therapy. We then elaborate on the ongoing attempts to further lower the doses delivered to the heart during therapeutic courses of radiation.

Immune Escape in Glioblastoma: Mechanisms of Action and Implications for Immune Checkpoint Inhibitors and CAR T-Cell Therapy

Glioblastoma, the most common primary brain cancer in adults, is characterized by a poor prognosis and resistance to standard treatments. The advent of immunotherapy has revolutionized the treatment of several cancers in recent years but has failed to demonstrate benefit in patients with glioblastoma. Understanding the mechanisms by which glioblastoma exerts tumor-mediated immune suppression in both the tumor microenvironment and the systemic immune landscape is a critical step towards developing effective immunotherapeutic strategies. In this review, we discuss the current understanding of immune escape mechanisms in glioblastoma that compromise the efficacy of immunotherapies, with an emphasis on immune checkpoint inhibitors and chimeric antigen receptor T-cell therapy. In parallel, we review data from preclinical studies that have identified additional therapeutic targets that may enhance overall treatment efficacy in glioblastoma when administered alongside existing immunotherapies.

The Impact of Medicaid Expansion on Patients with Cancer in the United States: A Review

Since 2014, American states have had the option to expand their Medicaid programs as part of the Affordable Care Act (ACA), which was signed into law by former President Barack H. Obama in 2010. Emerging research has found that Medicaid expansion has had a significant impact on patients with cancer, who often face significant financial barriers to receiving the care they need. In this review, we aim to provide a comprehensive examination of the research conducted thus far on the impact of Medicaid expansion on patients with cancer. We begin with a discussion of the history of Medicaid expansion and the key features of the ACA that facilitated it. We then review the literature, analyzing studies that have investigated the impact of Medicaid expansion on cancer patients in terms of access to care, quality of care, and health outcomes. Our findings suggest that Medicaid expansion has had a positive impact on patients with cancer in a number of ways. Patients in expansion states are more likely to receive timely cancer screening and diagnoses, and are more likely to receive appropriate cancer-directed treatment. Additionally, Medicaid expansion has been associated with improvements in cancer-related health outcomes, including improved survival rates. However, limitations and gaps in the current research on the impact of Medicaid expansion on patients with cancer exist, including a lack of long-term data on health outcomes. Additionally, further research is needed to better understand the mechanisms through which Medicaid expansion impacts cancer care.

A systematic review of craniospinal irradiation for leptomeningeal disease: past, present, and future

PURPOSE

Leptomeningeal disease (LMD) is a rare but deadly complication of cancer in which the disease spreads to the cerebrospinal fluid and seeds the meninges of the central nervous system (CNS). Craniospinal irradiation (CSI) involves treatment of the entire CNS subarachnoid space and is occasionally used as a last-resort palliative therapy for LMD.

METHODS

This review examined literature describing the role of CSI for LMD from solid and hematologic malignancies in adults. A search for studies published until September 1, 2020 was conducted using PubMed database.

RESULTS

A total of 262 unique articles were identified. Thirteen studies were included for analysis in which a total of 275 patients were treated with CSI for LMD. Median age at time of irradiation was 43 years, and most patients had KPS score of 70 and higher. The most common cancers resulting in LMD were acute lymphocytic leukemia, breast cancer, and acute myelogenous leukemia. Median CSI dose was 30 Gy and 18% of patients were treated with proton radiation. 52% of patients had stable-to-improved neurologic symptoms. Median overall survival for the entire cohort was 5.3 months. Patients treated with marrow-sparing proton radiation had median OS of 8 months. The most common treatment toxicities were hematologic and gastrointestinal events.

CONCLUSIONS

Despite advances in systemic and radiation therapies, LMD remains a devastating end-stage complication of some malignancies. Treatment-related toxicities can be a significant barrier to CSI delivery. In select patients with LMD, marrow-sparing proton CSI may provide safer palliation of symptoms and prolong survival.

Where are we with proton beam therapy for thoracic malignancies? Current status and future perspectives

Radiation therapy (RT) plays an important role in the curative treatment of a variety of thoracic malignancies. However, delivery of tumoricidal doses with conventional photon-based RT to thoracic tumors often presents unique challenges. Extraneous dose deposited along the entrance and exit paths of the photon beam increases the likelihood of significant acute and delayed toxicities in cardiac, pulmonary, and gastrointestinal structures. Furthermore, safe dose-escalation, delivery of concomitant systemic therapy, or reirradiation of a recurrent disease are frequently not feasible with photon RT. In contrast, protons have distinct physical properties that allow them to deposit a high irradiation dose in the target, while leaving a negligible exit dose in the adjacent organs at risk. Proton beam therapy (PBT), therefore, can reduce toxicities with similar antitumor effect or allow for dose escalation and enhanced antitumor effect with the same or even lower risk of adverse events, thus potentially improving the therapeutic ratio of the treatment. For thoracic malignancies, this favorable dose distribution can translate to decreases in treatment-related morbidities, provide more durable disease control, and potentially prolong survival. This review examines the evolving role of PBT in the treatment of thoracic malignancies and evaluates the data supporting its use.

RADI-29. BIOLOGIC SUBTYPES OF BREAST CANCER BRAIN METS AS A PREDICTOR OF LOCAL CONTROL AFTER STEREOTACTIC RADIOSURGERY

INTRODUCTION: Brain metastases (BM) are diagnosed in approximately 15% of breast cancer (BC) patients. Biologic subtype is predictive of loco-regional recurrence following breast conserving therapy and/or mastectomy with the highest risk in the ER-/PR-/HER2- (TN) subtype. The aim of this study is to determine whether biologic subtype is predictive of local control (LC) in BC patients with BM treated with Stereotactic Radiosurgery (SRS). MATERIALS/METHODS: All patients underwent LINAC-based SRS at our institution. Patients were subdivided into three biologic subtypes: ER+/Her2- (Luminal), Her2+, and TN (Basal). Kaplan Meier method was used to estimate the overall survival (OS). Cox proportional hazard model was used to analyze association of local failure (LF) with biologic subtypes. This is an IRB-approved single center retrospective study. RESULTS: 108 BC BM in 50 consecutive patients were included in this study with a median follow up of 11.1 months. The median disease-specific GPA was 2.0, and all patients received systemic chemotherapy and/or hormonal therapy. The 12 month LC rates for the entire cohort were 85%, 87%,49% for Luminal, Her2+ and Basal, respectively, with a significantly shorter LC for the basal sub-type (p=0.014). The 12 month OS rates were 83%, 88%, 80% for Luminal, Her2+ and Basal, respectively with a no significant difference in OS among the subgroups. 24% of the lesions were treated with salvage whole brain radiation therapy. CONCLUSIONS: This study shows that in BC patients with BM treated with SRS, biologic subtype impacts LC but not OS. Consideration of radiation treatment intensification or altered fractionation to improve LC may be indicated for the TN subtype. Further multi-center studies are necessary to corroborate our results.

Risk of prolonged opioid use among cancer patients undergoing curative intent radiation therapy for head and neck malignancies

OBJECTIVE

Patients undergoing radiation treatment (RT) for head and neck malignancies often suffer significant disease- and treatment-related pain requiring opioids for effective management. However, the prevalence and associated risk factors of prolonged opioid use in this population remain poorly characterized. We sought to quantify the rate of prolonged opioid use among opioid naïve patients receiving curative-intent RT for head and neck malignancies and to identify associated risk factors.

METHODS

We retrospectively identified patients who had undergone RT for head and neck malignancies at our institution between Jan 2011 and Sept 2017. Our primary endpoint was persistent opioid use 6-months following completion of RT. Patients were included if they were opioid-naïve, underwent curative intent RT, had adequate follow-up, and did not have residual or recurrent disease within our follow-up period. Univariable and multivariable logistic regression was utilized to identify risk factors for prolonged opioid use.

RESULTS

We identified 311 patients meeting our inclusion criteria; 40 (12.9%) continued to use opioids 6-months following RT. Univariable analysis found current smoking, alcohol abuse, RT dose, treatment to the bilateral necks, induction chemotherapy, concurrent chemotherapy, PEG tube, daily milligram morphine equivalents, and adjuvant analgesic medication use to be positively associated with prolonged opioid use; prior surgery was negatively associated with prolonged opioid use. Delivery of induction chemotherapy (OR 2.86, CI (95%) 1.32-6.21) and alcohol abuse (OR 3.75, CI (95%) 1.66-8.47) remained statistically significant on multivariable analysis.

CONCLUSION

The prevalence of prolonged opioid use in previously opioid naïve patients undergoing curative intent head and neck RT was just under 13%. Patients with history of alcohol abuse and those who undergo induction chemotherapy were most at risk.

Dose Selection for Multiple Myeloma in Modern Era

PURPOSE

The management of multiple myeloma (MM) has evolved over the past 20 years, secondary to novel biologic therapeutics. Radiation therapy remains an important intervention in the management of painful lytic bone lesions. However, the currently used radiation therapy regimens were developed in the pre-biologic therapy era. The goal of this study is to assess the effects of dose and fractionation in pain control for patients with MM in the modern era.

METHODS AND MATERIALS

We conducted a retrospective study based on data collected from patients who received radiation therapy at our institute between 2007 and 2017. A total of 130 patients (266 treatment sites) were included in this study. Univariate Cox proportional hazards models were used to analyze the association of risk of pain recurrence with treatment characteristics and compute the hazard ratios (HRs).

RESULTS

The median follow-up time was 14 months. Patients who received a total dose of 20 to <30 Gy (including 20 Gy) had a significantly lower probability of pain recurrence when compared with those who received <20 Gy (HR, 0.36; 95% confidence interval, 0.14-0.94; P = .0365). There was no statistically significant difference in treatment response or pain recurrence between the different fraction numbers and sizes. However, we noted a trend indicating lower pain recurrence in the group that received 6 to 10 fractions of radiation therapy (P = .06). Among the most commonly used regimens, 8 Gy in a single fraction resulted in a statistically significant increased chance of pain recurrence compared with 20 Gy in 10 fractions and a borderline statistically significant increased chance of pain recurrence when compared with 30 Gy in 10 fractions.

CONCLUSIONS

Radiation therapy remains highly effective at managing lytic bone lesions in patients with MM, and 6- to 10-fraction treatment courses are equally as effective as longer courses at treating these lesions. Treatment with 20 Gy in 10 fractions resulted in a significantly lower probability of pain recurrence when compared with 8 Gy in 1 fraction.

The Safety Profile of Concurrent Therapy for Multiple Myeloma in the Modern Era

Purpose

The management of multiple myeloma has evolved in the modern era, partially owing to the increasing number of biologic therapeutics. Nonetheless, radiation remains an important treatment in the management of painful lytic lesions from multiple myeloma. The goal of this study is to evaluate the side effect profile of radiation therapy (RT) while patients are concurrently treated with biologic agents.

Methods and Materials

We conducted a retrospective study based on data collected from patients receiving RT at our institute from 2007 to 2017. A total of 130 patients (279 treatment sites) were included in this study with a median follow-up time of 14 months. Patients were required to be receiving a biological agent at least within 1 month before starting and up to 1 month after RT. Generalized estimating equations with a log link function and binomial distribution were used to estimate the prevalence ratio (PR) and corresponding 95% confidence interval (CI) and compare the side effects between patients with RT alone and RT + biologic agent.

Results

The median age of all patients in our cohort was 64 years, with 53 men (58.9%) and 37 women (41.1%). The mean Karnofsky performance status score of all cohorts was 80. No significant difference in incidence of acute (PR: 1.33; 95% CI, 0.80-2.22; P = .2660) or subacute (PR: 0.90; 95% CI, 0.49-1.67; P = .7464) toxicities was found between patients with or without biologic agents who were treated concurrently with RT. No significant difference was found in reduction in laboratory values between patients with or without biologic agents treated concurrently with RT for white blood cells (P = .6916), platelets (P = .7779), or hematocrit (P = .0858).

Conclusions

Our study did not detect any significant toxicity rates from palliative radiation while patients were concurrently treated with biologic agents.

Long-term treatment of Cushing's disease with pasireotide: 5-year results from an open-label extension study of a Phase III trial

BACKGROUND

Treating hypercortisolism in patients with Cushing's disease after failed surgery often requires chronic medication, underlining the need for therapies with favourable long-term efficacy and safety profiles.

METHODS

In a randomised, double-blind study, 162 adult patients with persistent/recurrent or de novo Cushing's disease received pasireotide. Patients with mean urinary free cortisol at/below the upper limit of normal or clinical benefit at month 12 could continue receiving pasireotide during an open-ended, open-label phase, the outcomes of which are described herein.

RESULTS

Sixteen patients received 5 years of pasireotide treatment. Among these, median (95% confidence interval) percentage change from baseline in mean urinary free cortisol was -82.6% (-89.0, -41.9) and -81.8% (-89.8, -67.4) at months 12 and 60. Eleven patients had mean urinary free cortisol ≤ upper limit of normal at month 60. Improvements in clinical signs were sustained during long-term treatment. The safety profile of pasireotide at 5 years was similar to that reported after 12 months. Fifteen of 16 patients experienced a hyperglycaemia-related adverse event; glycated haemoglobin levels were stable between months 6 and 60. Adverse events related to hyperglycaemia, bradycardia, gallbladder/biliary tract, and liver safety were most likely to first occur by month 6; adverse event severity did not tend to worsen over time.

CONCLUSIONS

This represents the longest prospective trial of a medical therapy for Cushing's disease to date. A subset of patients treated with pasireotide maintained biochemical and clinical improvements for 5 years, with no new safety signals emerging. These data support the use of pasireotide as an effective long-term therapy for some patients with Cushing's disease.

Predictors of Complete Response and Disease Recurrence Following Chemoradiation for Rectal Cancer

OBJECTIVE

Approximately 10-40% of rectal patients have a complete response (CR) to neoadjuvant chemoradiation (CRT), and these patients have improved survival. Thus, non-operative management ("watch-and-wait" approach) may be an option for select patients. We aimed to identify clinical predictors of CR following CRT.

METHODS

Patients treated with definitive CRT for T3-T4, locally unresectable T1-T2, low-lying T2, and/or node-positive rectal cancer from August 2004 to February 2015 were retrospectively reviewed. Most patients were treated with 50.4 Gy radiation and concurrent 5-fluoruracil or capecitabine. Patients were considered to have a CR if surgical pathology revealed ypT0N0M0 (operative management), or if they had no evidence of residual disease on clinical and radiographic assessment (non-operative management). Statistical analysis was carried out to determine predictors of CR and long-term outcomes.

RESULTS

Complete records were available on 138 patients. The median follow-up was 24.5 months. Thirty-six patients (26.3%) achieved a CR; 30/123 operatively managed patients (24.5%) and 6/15 (40%) non-operatively managed patients. None of the 10 patients with mucinous adenocarcinoma achieved a CR. Carcinoembryonic antigen (CEA) ≥5 μg/L at diagnosis (OR 0.190, 95% CI 0.037-0.971, p = 0.046), tumor size ≥3 cm (OR 0.123, 95% CI 0.020-0.745, p = 0.023), distance of tumor from the anal verge ≥3 cm (OR 0.091, 95% CI 0.013-0.613, p = 0.014), clinically node-positive disease at diagnosis (OR 0.201, 95% CI 0.045-0.895, p = 0.035), and interval from CRT to surgery ≥8 weeks (OR 5.267, 95% CI 1.068-25.961, p = 0.041) were independent predictors of CR. The CR group had longer 3-year distant metastasis-free survival (DMFS) (93.7 vs. 63.7%, p = 0.016) and 3-year disease-free survival (DFS) (91.1 vs. 67.8%, p = 0.038). Three-year locoregional control (LRC) (96.6 vs. 81.3%, p = 0.103) and overall survival (97.2 vs. 87.5%, p = 0.125) were higher in the CR group but this did not achieve statistical significance. CR was not an independent predictor of LRC, DMFS, or DFS.

CONCLUSION

CEA at diagnosis, tumor size, tumor distance from the anal verge, node positivity at diagnosis, and interval from CRT to surgery were predictors of CR. These clinical variables may offer insight into patient selection and timing of treatment response evaluation in the watch-and-wait approach.

Outcomes of rectal cancer with liver oligometastases

PURPOSE

In patients with oligometastatic colorectal cancer to the liver, long term survival is possible and a multi-modality treatment approach may be considered. This is a report of a single institution experience of oligometastatic rectal cancer patients after treatment of the primary tumor and pelvic lymph nodes with extended course chemoradiation therapy.

METHODS

Between 2004 and 2013, 26 oligometastatic rectal cancer patients with liver metastases were treated with extended course chemoradiation at our institution followed by total mesorectal excision (TME). Amongst these there were 17 men and 9 women. The mean age at the time of diagnosis was 59.8 years, with a range from 36 to 87 years of age. Eleven patients had metastases in other sites in addition to liver, and one patient in our cohort had lung metastasis with no liver metastasis. Kaplan-Meier method was used to generate overall survival (OS), progression free survival (PFS), distant metastases (DM) and local control (LC).

RESULTS

OS rates were 95%, and 70% at 12 and 24 months respectively, with a mean survival time of 40.5 months. PFS rates were 91% and 36% at 12 and 24 months respectively, with a mean PFS time of 23.1 months. LC rates were 91% and 66% at 12 and 24 months respectively. DM rates were 0% and 61% at 12 and 24 months respectively. Finally, when censoring deaths, progression of liver metastases and distant progression, Kaplan-Meier analysis demonstrated five events of local failure.

CONCLUSIONS

This series demonstrated an OS of 70% at 24 months, with a mean survival of 40.5 months. Significantly, LC was only 66% despite the use of extended course chemoradiation and TME. This data suggests that many patients with oligometastatic rectal cancer will survive past 2 years, and that a substantial number will fail locally as well as distantly. Therefore, a multimodality approach is reasonable. Recent data suggests that a hypofractionated radiation regiment of 25 Gy in 5 Gy fractions allows an equivalent LC compared to extended course chemoradiation with 50.4 Gy in 1.8 Gy fractions. A short course of radiation may be more consistent with the goals of care of the oligometastatic rectal cancer patient who is at high risk of recurrence.

High variability in baseline urinary free cortisol values in patients with Cushing's disease

OBJECTIVE

Twenty-four-hour urinary free cortisol (UFC) sampling is commonly used to evaluate Cushing's syndrome. Because there are few data on UFC variability in patients with active Cushing's disease, we analysed baseline UFC in a large patient cohort with moderate-to-severe Cushing's disease and assessed whether variability correlates with hypercortisolism severity. These data will help clinicians establish the minimum number of UFC samples required to obtain reliable data.

DESIGN

Observational study (enrolment phase of Phase III study).

METHODS

Patients (n = 152) with persistent/recurrent or de novo Cushing's disease and mean UFC (mUFC) ≥1·5×ULN (normal: 30-145 nmol/24 h) were included. Mean UFC level was calculated from four 24-h urine samples collected over 2 weeks.

RESULTS

Over 600 24-h UFC samples were analysed. The mUFC levels of samples 1 and 2 and samples 3 and 4 were 1000 nmol/24 h (SD 1872) and 940 nmol/24 h (SD 2148), respectively; intrapatient coefficient of variation (CV) was 38% for mUFC. The intrapatient CV using all four samples was 52% (95% CI: 48-56). The intrapatient CV was 51% (95% CI: 44-58) for samples 1 and 2, 49% (95% CI: 43-56) for samples 3 and 4 and 54% (95% CI: 49-59) for samples 1, 2 and 3. Variability in mUFC increased as UFC levels increased. There were no correlations between UFC and clinical features of hypercortisolism.

CONCLUSIONS

There is intrapatient variability of approximately 50% in 24-h UFC measurements, which is relevant to targets set to estimate any treatment effect. Analysing more than two 24-h collection periods in individual patients does not result in a relevant decrease in variability. Interestingly, UFC levels did not correlate with hypercortisolism severity.

Distant metastasis is a critical mode of failure for patients with localized major salivary gland tumors treated with surgery and radiation

Objectives

Excellent local-regional control can be achieved for major salivary gland tumors treated with surgery and post-operative radiotherapy. We evaluated the cumulative incidence and predictors of distant metastasis in high-risk major salivary gland tumors.

Methods

Between 1990 and 2011, 200 patients with major salivary gland tumors received post-operative radiotherapy at our center. The patients' median age was 60 years. Patients had primary tumors of the parotid gland (84%), submandibular (16%), and one sublingual gland. Among the patients, 34% had T3-T4 tumors, 32% had nodal involvement. Other high-risk features included close/positive margins and high grade tumors. The median RT dose was 63 Gy.

Results

With a median follow-up of 50 months, the 5-year local control and regional control were 88% and 94%, respectively. The 5-year freedom from distant metastasis was 73%. The median overall survival was 14.6 years corresponding to a 5 and 10-year overall survival of 77% and 59%, respectively. T category and nodal involvement were independent predictors of distant metastasis. Nodal involvement was also an independent predictor of overall survival.

Conclusions

Distant relapse was the predominant mode of failure despite excellent local-regional control in high-risk major salivary gland tumors. Both advanced T category and nodal involvement were independent predictors of distant metastasis. More effective systemic therapy is needed to combat distant relapse.

In vivo response to growth hormone-releasing peptide-6 in adrenocorticotropin-dependent Cushing's syndrome by lung carcinoid tumor is associated with growth hormone secretagogue receptor type 1a mRNA expression

GH secretagogues (GHS) have been used for the differential diagnosis of ACTH-dependent Cushing's syndrome (CS) since 1997 due to their ability to increase ACTH and cortisol levels in Cushing's disease. The aim of this study was to correlate ACTH response to GH-releasing peptide-6 (GHRP-6) in vivo with GH secretagogue receptor type 1a (GHSR-1a) mRNA expression in a patient with lung carcinoid tumor. The patient was a 26-yr-old male with diagnosis of ACTH-dependent CS. He presented negative responses to human CRH and desmopressin tests; yet, a significant increase in ACTH after the GHRP-6 test was observed. Sellar magnetic resonance imaging (MRI) showed slight posterior hypointensity, but bilateral petrosal sinus sampling did not show central gradient. Computed tomography (CT) and MRI of thorax/abdomen/cervical were negative and 111In-pentetreotide scintigraphy depicted abnormal uptake on the right lung. The patient was submitted to right thoracotomy for exeresis of lung nodule and hilar lymph node which were characterized as atypical lung carcinoid tumor and he presented clinical and laboratorial remission after surgery. GHSR-1a mRNA expression was studied with real-time quantitative PCR and tumor data were compared with fragments of normal lung and pituitary. There was a higher GHSR-1a expression in the lung carcinoid tumor as compared with normal tissues. The ACTH response to GHRP-6 in a patient with ectopic ACTH production by a lung carcinoid tumor was associated with GHSR-1a expression in the tumor tissue, suggesting an association between GHSR-1a mRNA overexpression and the in vivo response to GHS.

Pitfalls in pituitary diagnosis: peculiarities of three cases

Due to the increasing availability and sensitivity of diagnostic methods, biochemical and imaging abnormalities of pituitary function and anatomy are becoming more frequent. Hyperprolactinaemia was found in three women without any prolactin (PRL) related clinical features. All three patients had normal libido, regular menses with evidence of ovulation, no galactorrhoea, and normal FSH, LH, TSH and free T4 serum levels. Magnetic resonance imaging (MRI) of the sellar region showed images that were compatible with pituitary microadenomas in all three cases. Due to the discordance between laboratory and clinical features, we searched for the presence of PRL aggregates with high molecular weight and low biological activity (macroprolactinaemia). Initially, we screened with a polyethylene glycol precipitation method, and then confirmed the presence of macroprolactinaemia by chromatography. All three cases screened positive for the presence of macroprolactinaemia. MRI alterations, compatible with pituitary microadenomas, may be due to true microincidentalomas, normal anatomical variations or imaging artefacts. In conclusion, we have described the presence of double diagnostic pitfalls that might lead to unnecessary medical or surgical intervention.

Adrenocorticotropin levels do not change during early recovery of transsphenoidal surgery for ACTH-secreting pituitary tumors

In patients with ACTH-secreting pituitary tumor the peri-tumoral normal corticotrophs were supposed to be suppressed by cronic hypercortisolemia since frequently they develop transient secondary adrenal insufficiency after pituitary tumor resection and during early postoperative days. We evaluated the ACTH dynamics during transsphenoidal surgery in 16 patients with ACTH-secreting pituitary tumors (6 cured by surgery, 8 not cured Cushing's disease patients and 1 cured by surgery and 1 not cured Nelson's syndrome patients) and tested the hypothesis that in these patients, ACTH secretion from the peri-tumoral normal corticotrophs is inhibited and hence removal of the entire tumor should result in subtle postoperative reduction in plasma ACTH. Blood samples for ACTH determination were obtained from 14 Cushing's disease patients immediately before pituitary gland manipulation and 10, 30, 60, 90, 120, 150 and 300 min after pituitary tumor resection and on postoperative day one. In Nelson's syndrome patients the blood sample was obtained only after tumor removal. All patients received intravenous hydrocortisone during surgery and on the first postoperative day. Patients were considered cured by surgery if they presented adrenal insufficiency after hydrocortisone withdrawal. Mechanical pituitary manipulation induced increase in ACTH level. In all 14 Cushing's disease patients (cured and not cured), mean plasma ACTH levels were significantly greater 10 min after pituitary tumor resection (54.4+/-12.8 pmol/l) than in the premanipulation period (ACTH=26.3+/-5.3 pmol/l) (p=0.005). In Cushing's disease patients, the ACTH levels did not change significantly until 300 min after pituitary tumor resection either in those 6 patients cured by surgery (at 10 min after pituitary tumor resection ACTH was 54.4+/-12.8 pmol/l for all 14 Cushing's disease patients and at 300 min after tumor removal ACTH was 39.0+/-12.6 pmol/l for cured and 41.3+/-15.7 pmol/l for not cured Cushing's disease patients). The ACTH level also persisted high until 300 min after complete pituitary tumor resection in one cured patient with Nelson's syndrome. ACTH level does not change in the early recovery period after ACTH-secreting pituitary tumor, even in those cured patients, and probably peri-tumoral normal corticotrophs are not completely suppressed by cronic hypercortisolemia (and acute glucocorticoid administration) when these patients are under intense stress, like transsphenoidal surgery. Mechanical pituitary manipulation may induce ACTH release in patients with ACTH-secreting pituitary tumors but probably does not interfere in the maintenance of high ACTH-levels during the early postoperative period, since ACTH half-life is only 8-15 min. In patients with ACTH-secreting pituitary tumors, the behavior of the human hypothalamic-pituitary-adrenal system during transsphenoidal surgery does not conform to the specifications of a negative feedback mechanism.

[Identical twins discordant for Cushing's disease: case report[]

Cushing's disease is rare in children and its occurrence in identical twins is extremely rare. This paper reports on identical twins discordant for Cushing's disease. One of them first presented with a cushingoid phenotype by the age of 10. Her evaluation showed an increased urinary free-cortisol and serum ACTH. Her pattern in the dexametazone suppression tests was compatible with Cushing's disease. MRI disclosed a pituitary macroadenoma which was removed by the transesphenoidal approach. Immunohistochemical studies of the tumor showed the presence of ACTH-producing cells. The patient went into clinical and laboratorial remission after surgery. She re-started to grow after the disappearance of the Cushing's phenotype but she is still shorter than her healthy sister. The latter remains disease-free 4 years after her sister's diagnosis. This represents the third such case reported in the literature. Our findings suggest that acquired factors may be responsible for the genesis of Cushing's disease.

[Subclinical apoplexy in pituitary tumors]

Acute pituitary apoplexy is a rare event, even in patients with pituitary macroadenomas. On the other hand, the presence of necrotic/hemorrhagic areas, especially in macroadenomas, seems to be more common than earlier reported in the CT period. After the introduction of MR in the presurgical workup of these patients, these apopleptic areas have been more easily diagnosed preoperatively. Forty consecutive patients with pituitary macroadenomas were studied with high-resolution 1.5 T T1 coronal, sagittal and axial slices over the sellar region. Special attention was paid in the detection of necrotic, cystic and hemorrhagic areas within these tumors. Ten patients had hemorrhagic/necrotic areas within their tumors, without any sign or symptom of acute apoplexy. These areas varied from small (2 mm) to very large (30 mm) ones. Seven patients had non-secreting tumors, 2 GH and 1 prolactin secreting tumors, which is the same profile of secretory pattern for the whole series (40 patients). The clinical picture included (other than that caused by endocrine secretion) slowly progressive (but not acute) visual loss (n = 8) and headache (n = 3). After surgical decompression of the surrounding structures and visual apparatus, which was facilitated by the presence of the necrotic areas, there was visual improvement in 6 patients and headache resolution in 2. The presence of asymptomatic apopletic areas in these macroadenomas and their absence in microadenomas as can be seen in the literature suggest that they are related more to the size of the tumor than to its endocrine secretion pattern. This is in agreement with a vascular insufficiency hypothesis in the pathogenesis of these lesions.

A study of patients with Nelson's syndrome

OBJECTIVE

The prevalence of Nelson's syndrome has varied greatly, at least in part because of the variability of the diagnostic criteria employed by different authors. We define Nelson's syndrome as the presence of an enlarging pituitary tumour associated with elevated fasting plasma ACTH levels and hyperpigmentation in patients with Cushing's disease after bilateral adrenalectomy. We have compared patients with Cushing's disease who developed Nelson's syndrome after bilateral adrenalectomy with those who did not. Our objective was to find differences between the two groups which might predict the development of Nelson's syndrome.

PATIENTS AND METHODS

We have reviewed the records of 30 patients with Cushing's disease after adrenalectomy, and divided them into two groups; I: 14 who developed Nelson's syndrome and II, 16 who did not. The two groups of patients were compared in their clinical, laboratory and imaging data as well as in the therapeutic procedures that preceded the adrenalectomy.

RESULTS

The comparison between the two groups of patients demonstrated a highly significant difference in relation to the development of cutaneous hyperpigmentation (100% in group I and 19% in group II) and neuro-ophthalmological symptoms (21% in group I and 0% in group II) after adrenalectomy. There were no significant differences in laboratory data before adrenalectomy. After adrenalectomy, plasma ACTH levels increased significantly in the patients of both groups, but to much higher levels in those who developed Nelson's syndrome. Plasma ACTH concentrations above 154 pmol/l occurred only in the subjects with Nelson's syndrome. Before adrenalectomy, a pituitary tumour was more frequent in the patients who developed Nelson's syndrome (55% vs. 33% at transsphenoidal pituitary exploration). Pituitary surgery and irradiation were undertaken before adrenalectomy in approximately equal numbers of patients in each group.

DISCUSSION

The prevalence of Nelson's syndrome was 47% in our series of 30 patients with Cushing's disease after bilateral adrenalectomy. No clinical or laboratory data before adrenalectomy predicted the development of the syndrome. The value of prophylactic pituitary irradiation could not be evaluated from our clinical material. However, after adrenalectomy, the presence of hyperpigmentation and ACTH levels above 154 pmol/l had positive predictive value for the development of Nelson's syndrome. In this situation magnetic resonance imaging (MRI) of the pituitary is mandatory and, if no tumour is detected, MRI should be repeated at intervals.

[Pituitary apoplexy followed by endocrine remission. Report of two cases]

Pituitary apoplexy is rare and endocrine remission in patients with apopletic secreting pituitary adenomas is even rarer. This study reports on two patients with pituitary macroadenomas (one with Cushing's disease and the other with acromegaly) in whom endocrine remission occurred after apoplexy. The first patient had Cushing's disease and had an ictus of headache and vomiting after which she started a progressive remission of hypercortisolism. A post-apoplexy MRI disclosed persistence of a sellar and supra-sellar mass. She was submitted to transesphenoidal surgery. An hypertensive hemorrhagic cyst was found with no tumor. The second patient had acromegaly. While performing a LHRH-stimulation test he had an ictus of headache, vomiting, no visual loss and appearance of diabetes insipidus. A CT scan disclosed an intrasellar hematoma. Despite the size of the tumor and since there was no visual impairment, this patient was followed up without surgery. Imaging follow-up showed a progressive shrinkage and disappearance of the mass, which was corroborated by endocrine remission. A high rate of recurrence is reported in such patients in the literature. Both patients are being currently followed-up on a long-term basis.

Somatotrophic and corticotrophic function outcome after transesphenoidal surgery in patients with sellar tumors and pre-operative endocrine deficits

Sixteen patients with sellar tumors that were treated surgically and who had pre-operative somatotrophic and corticotrophic function deficits were submitted to pre- and early post-operative insulin tolerance tests (ITTs). Seven patients had non-functioning adenomas, 5 had prolactinomas, 3 had craniopharyngioma and 1 had cordoma of the clivus. All patients had macro-tumors and none received radiotherapy within the studied period. Seven patients had GH, 4 had cortisol and 5 had both GH/cortisol function pre-operative deficit. Five patients with isolated GH, 4 with isolated cortisol and 3 with both GH/cortisol deficiencies showed a postoperative functional recovery. New cortisol secretion deficits were observed in 2 patients postoperatively and both required long-term steroid replacement. These data suggest that preoperative endocrine deficits may be reversible after surgical decompression of the sellar region and that new endocrine deficits are rarely seen after surgery. All such patients should be tested postoperatively from an endocrinological point of view to reevaluate the need for replacement therapies.

Resistance to vasopressin action on the kidney in patients with Cushing's disease

OBJECTIVE

To assess the plasma levels and action of arginine vasopressin (AVP) in patients with Cushing's disease. There are many reports that patients with Addison's disease have increased AVP levels associated with hyponatraemia and hypoosmolality, but none on the dynamics of secretion of this neurohormone during osmolality-based stimulation in patients with chronic hypercortisolism.

DESIGN AND SUBJECTS

The plasma AVP concentration and the urinary and plasma osmolality after a 7.5-h water deprivation test (WDT) were evaluated in 13 patients with Cushing's disease and 15 normal (control) individuals. In patients with Cushing's disease we also assessed the urinary osmolality in response to 10 micrograms i.v. desmopressin (DDAVP) administered at the end of the WDT.

RESULTS

At the end of the WDT, urinary osmolality was significantly lower in patients with Cushing's disease (511.5 +/- 148.5 mOsm/l) than in the normal subjects (981.1 +/- 107.1 mOsm/l, P < 0.001), whereas plasma osmolality did not differ between the two groups. Consequently, the urine/plasma osmolality ratio (Uosm/Posm) was lower in patients with Cushing's disease than in normal individuals (1.8 +/- 0.5 compared with 3.4 +/- 0.4, P < 0.001). The AVP concentration also was greater (7.3 +/- 3.1 pmol/l) in those with Cushing's disease than in the controls (3.9 +/- 2.3 pmol/l, P < 0.005). After administration of DDAVP to the hypercortisolaemic patients, the urinary osmolality attained (718.0 +/- 200.0 mOsm/l) was still lower than that in the normal group at the end of WDT (P < 0.005).

CONCLUSIONS

Patients with Cushing's disease presented higher AVP levels and smaller Uosm/Posm ratios than normal subjects. After DDAVP, the patients with Cushing's disease were unable to concentrate the urine adequately. These data suggest that the kidney shows resistance to the action of both endogenous and exogenous AVP in patients with Cushing's disease.

Effect of glycemic control on growth hormone and IGFBP-1 secretion in patients with type I diabetes mellitus

Growth hormone (GH) secretion disorders have been reported in poorly controlled type I diabetes mellitus patients. Our work was aimed to evaluate GH secretion in 9 type I young diabetes mellitus patients as well as the low molecular weight IGF-binding protein secretion (IGFBP-1) in 5 of them. The patients did not show any signs of malnutrition or neurovascular complications, neither were they on any medication except for insulin. The study protocol included blood samples collection during a 24-h period for measurement of glucose, glycated hemoglobin, GH IGF-I and IGFBP-1 levels under two situations: on poor glycemic control and after 2-3 months on better control through systematic diet, low in carbohydrates and increase in insulin dosage. GH secretion data were analyzed by Cluster algorithm for pulsatility parameters; for rhythm assessment Cosinor method was used. The first study (poor control) reported significant increase of GH maximal and incremental amplitude and duration pulse values, when compared to the second study (better control). Mean 24-h secretion values as well mean GH for interpulse intervals (valleys) decreased, although not statistically significant. The fraction of pulsatile GH/24 h GH did not change significantly with better glycemic control. No changes in pulse frequency were observed. Mean IGF-I concentrations were significantly higher when patients were on better glycemic control. An ultradian variation for GH secretion was noticed in the first study (poor control) and a circadian variation in the second one (better control). IGFBP-1 analysis showed significant decrease of the mean 24-h values under better glycemic control. Linear regression analysis demonstrated a correlation between IGFBP-1 levels and fasting glucose levels. A circadian variation was present in IGFBP-1 secretion, irrespective of glycemic control. Therefore, we concluded that for type I diabetic patients: 1. GH secretion is increased on poor control, through maximal, incremental amplitude and pulse duration values; 2. IGFBP-1 values were significantly reduced and IGF-1 levels significantly higher after better glycemic control; 4. GH ultradian secretion is reported on poor control, and circadian on the better one, 5. IGFBP-1 circadian secretion occurred irrespective of glycemic control.

Pulsatile release and circadian rhythms of thyrotropin and prolactin in children with growth hormone deficiency

We have measured mean concentrations and have appraised the pulsatile nature of thyrotropin (TSH) and prolactin (PRL) release in children with classical GH deficiency (GHD; n = 4) and neurosecretory GH dysfunction (NSD; n = 4) and have compared the results with those obtained in children with constitutional delay (control; n = 4). Blood samples were obtained at 20-min intervals for 24 h. Pulse analysis of TSH and PRL was undertaken using the Cluster pulse detection algorithm. Circadian rhythmicity of TSH and PRL was assessed using cosinor analysis. The mean 24-h concentration of GH in the control subjects was significantly higher than that obtained in the GHD and NSD groups. With regard to TSH, the mean serum concentration in the GHD and NSD group were higher than that of the control subjects. This augmentation reflects TSH pulses of large amplitude and area, and a higher interpulse valley mean rather than a difference in peak number or peak duration. No differences in mean PRL concentration or characteristics of PRL pulses were found between the control and GHD and NSD subjects. When the 24 h data sets were divided into day (0800-2000 h) and night (2000-0800 h), the mean nighttime TSH concentration was higher than the daytime concentration in the control, GHD, and NSD groups. Although there were no day versus night differences in TSH pulse frequency in either group, peak amplitude, area, and interpulse valley means were increased during the night in the control group, and peak area, duration, and amplitude mean in the NSD group. The nighttime mean PRL concentrations in the control, GHD, and NSD subjects were higher than those found during the day. This increase was accounted for by increases in PRL peak amplitude, area in the control group, and peak area, amplitude, and interpulse valley mean in the GHD and NSD groups. Cosinor analysis of the 24-h TSH and PRL data revealed clear circadian rhythmicity in all groups of subjects. These data suggest that GHD and NSD are associated with an increase in pulsatile TSH secretion due to an increase in pulse amplitude and interpulse valley mean.

Growth hormone axis in cushing's syndrome

All levels of the growth hormone (GH), GH binding protein (GHBP), insulin-like growth factor (IGF) and IGF binding protein (IGFBP) axis are influenced by chronic hypercortisolism. Thus, there is a blunted response to GHRH alone or together with other stimuli associated with a marked suppression of endogenous GH secretion but accompanied by normal GHBP, normal to low IGF-1 and GHBPs 1 and 3 with the correspondent 41.5 and 38.5-kD molecular forms of the latter presenting values similar to normal. These findings may suggest enhanced GH sensitivity with normal or increased IGF-1 bioavailability to the correspondent tissue receptors. In conclusion, the glucocorticoid (GC)-induced target tissue resistance can neither be attributed to the suppression of the GH axis nor to changes in circulating GHBPs 1 and 3. However, it may be related either to the described 12-to-20-kD inhibitor(s) which antagonizes postbinding IGF-1 bioactivity (gene expression) and/or by the downmodulation of activator protein-1 (Fos/Jun) activity by the GC-GC receptor complex.

Growth hormone pulsatility in active and cured acromegalic subjects

GH secretion in normal subjects is periodic, with pulses prevailing during sleep. During the day (basal secretion), GH levels are, in general, undetectable. We studied GH secretion by cluster analysis, collecting samples every 20 min for 24 h in 44 subjects: 11 patients with active acromegaly; 16 "cured" acromegalics, and 17 normal subjects. The purpose of this study was to compare GH secretion between patients with active acromegaly and "cured" patients and between "cured" acromegalic patients and normal controls. The number of pulses detected through the 24-h GH profile was not different between acromegalic patients regardless of disease activity (17.5 +/- 4.4 vs. 15.0 +/- 6.0, respectively), but was different when active acromegalic patients and normal controls were compared (8.1 +/- 1.0; P < 0.05) and when cured acromegalic patients and normal controls were compared (P < 0.05). The GH pulsatile secretion/total GH secretion ratio was higher in normal controls than in acromegalic patients regardless of disease activity. We concluded that 1) the increases in GH pulsatility in active and cured acromegalic patients are similar, but most of the 24-h GH secretion is nonpulsatile; 2) half of the GH secretion in normal subjects occurs during pulses; 3) cured acromegalic patients, even those with normal GH and insulin-like growth factor I levels, do not recover a normal GH secretory pattern.

MRI of congenital pituitary insufficiency

We compared 1.5 T magnetic resonance (MR) image findings in 193 patients with congenital pituitary insufficiency. One hundred and thirty nine of the MR studies were obtained in patients who had isolated growth hormone deficiency (GHD). Other fifty-four patients had multiple pituitary hormone deficiency (MPHD). On MR images, normal anterior and posterior lobes of the pituitary gland can be clearly differentiated because the posterior lobe has a characteristic high intensity on T1-weighted images. In fifty-four patients, the high-intensity of the posterior lobe was not seen, but a similar high signal intensity was observed at the proximal stump in fifty-one patients. This high-intensity area is the newly formed ectopic posterior lobe, which also secrets anti-diuretic hormone just as the posterior lobe would. MR imaging can demonstrate the transection of the pituitary stalk and the formation of the ectopic lobe, revealing to be a usefull diagnostic tool in the definition of the type of alteration in growth defects of endocrine origin.

[Preservation of gonadotrophic function and pregnancy in Sheehan's syndrome: a case report and review of the literature]

Pregnancy occurring in patient with Sheehan's syndrome is seldom described. It depends on the preservation of LH and FSH secretion after the pituitary apoplexy event. PURPOSE--To report a patient with Sheehan's syndrome who became pregnant twice after the pituitary apoplexy episode and to discuss the maintenance of gonadotrophic function. METHOD--Clinical aspects are described and the pituitary reserve evaluation was performed as well as a computerized tomography and a magnetic resonance imaging of the brain. RESULTS--Gonadotrophic and thyrotrophic function were preserved and the neuroradiologic evaluation disclosed an empty sella turcica preservation of the posterior lobe of the hypophysis. CONCLUSION--A patient with Sheehan's syndrome is reported in whom the LH and FSH pituitary secretion was preserved allowing normal pregnancy twice after the pituitary apoplexy.

[Nephropathic cystinosis: report of 2 cases and review of the literature]

We describe two patients with infantile nephropathic cystinosis who presented nephrogenic diabetes insipidus in addition to Fanconi syndrome. After the diagnosis was confirmed by slit-lamp examination that showed crystallization of the cornea and by the presence of cystine crystals in the bone marrow, the patients underwent conservative and supportive treatment including correction of acidosis, replacement of fluid losses and protection from bone demineralization with replacement of phosphorus, calcium and vitamin D. Patient 1 deceased after an episode of bronchopneumonia complicated by profound acidosis. Patient 2 was started on cysteamine which effectively reduce cystine in body tissues and prevents or slows progression of end-organ damage.