The evolution of PRRT for the treatment of neuroendocrine tumors; What comes next?

Lu-177 has been developed for the treatment of patients with peptide receptor radionuclide therapy (PRRT). A second generation pure no-carrier-added Lu-177 has a high specific activity and has waste disposal advantages over the first generation carrier-added Lu-177. PRRT has recently been developed for the treatment of neuroendocrine tumors (NETs). The majority of pancreatic and gastroenteric NETs (GEP-NETs) express the somatostatin receptors (SSTRs) 2 and 5. These receptors can be specifically targeted with a somatostatin peptide analogue (DOTATOC/DOTATATE) which can be chelated to a positron emission tomography (PET) emitting radioisotope such as Ga-68 for imaging or to a ß-emitting radioisotope Lu-177 for therapy. A key advantage of this approach is that the receptor expression can be demonstrated by PET imaging before the patient is treated. Clinical studies in G1 and G2 GEP-NETS have demonstrated that PRRT is extremely effective in terms of progression free survival (PFS), symptom control and quality of life, with a well-established safety profile. A beneficial effect on outcome survival awaits to be confirmed. The first commercially available product Lu-177-DOTATATE was approved following the NETTER-1 trial in G1 and G2 GE-NETS. Lu-177-DOTATATE 7,4 GBq every 8 weeks for 4 cycles, together with octreotide LAR 30 mg monthly, demonstrated a median PFS of 28,4 months compared to 8,5 months for octreotide LAR 60 mg monthly. A second pivotal study COMPETE is currently in progress, comparing no carrier-added (n.c.a.) Lu-177-DOTATOC to the m-TOR inhibitor Everolimus in both GE-NETs and PNETs. Two studies, NETTER-2 and COMPOSE are currently underway in patients with high grade G2 and G3 NETs. Novel SSTR antagonists are being developed as next generation targeting molecules for SSTR2-expressing tumors. Antagonists have a higher tumor binding to receptors than agonists, opening up the potential indications for SSTR2 targeting to tumors which have a relatively lower expression of SSTR2 compared to NET such as small cell lung cancer, hepatocellular carcinoma and breast cancer. In addition to Lu-177, radioisotopes with different radiation properties such as Tb-161 and the α-emitter Ac-225 are being developed which have the potential to improve treatment efficacy across the range of G1 to G3 NETs.

Growth hormone (GH) replacement therapy in GH deficient adults: predictors of one-year metabolic and clinical response.

OBJECTIVE: This study investigated whether baseline status could predict the responsiveness to one-year growth hormone (GH) replacement therapy in adult GH deficient (GHD) patients. DESIGN: A total of 380 European patients with adult onset GHD due to non-functioning pituitary adenoma that had been enrolled in Pfizer International Metabolic Database (KIMS), and that had completed one year of GH replacement therapy within KIMS, were studied. RESULTS: The mean initial dose of GH was 0.22 (SEM 0.01) mg/day and after one year, the mean dose was 0.36 (0.01) mg/day. The mean insulin-like growth factor-I (IGF-I) SD score increased from -1.75 (0.08) at baseline to 0.47 (0.05) after one year. Quality of life (QoL)-Assessment of GHD in Adults (QoL-AGHDA), waist circumference, waist:hip ratio, and serum lipid pattern improved. Women received a higher dose of GH than men after one year, and demonstrated similar treatment response. In multiple stepwise forward regression analyses, the one-year changes in QoL-AGHDA score, waist:hip ratio, and serum low density lipoprotein-cholesterol (LDL-C) level correlated inversely with the baseline values of the same variable. In addition, the change after one year in QoL-AGHDA score correlated inversely with duration of hypopituitarism and baseline serum high density lipoprotein-cholesterol (HDL-C) level, and the change in waist:hip ratio correlated inversely, although more weakly, with baseline serum HDL-C level and UK citizenship and positively with baseline waist circumference and the initial GH dose. The change in serum LDL-C level additionally correlated inversely with the mean GH dose and duration of hypopituitarism and positively with UK citizenship. CONCLUSIONS: Baseline status could, with moderate strength, predict the responsiveness in the same variable whereas it could not, or only weakly, predict the response in other variables. Therefore, when the decision to start GH replacement is undertaken, as many outcome variables as possible should be evaluated in order to adequately evaluate the likelihood of clinical benefit. Finally, women have a similar response to GH replacement as men when individualised GH dosing schedules are employed and should therefore be selected for GH therapy to a similar extent.

Use of reflexology in managing secondary lymphoedema for patients affected by treatments for breast cancer: A feasibility study.

PURPOSE: The aim of this feasibility study was to examine the use of reflexology lymphatic drainage (RLD) in the treatment of breast-cancer related lymphoedema (BCRL) with a view to further research. METHODS: An uncontrolled trial was conducted with 26 women who had developed lymphoedema in one arm following treatment for breast cancer. Changes in upper-limb volumes and in participant concerns and wellbeing were measured. Qualitative data were also collected. RESULTS: A significant reduction in the volume of the affected arm was identified at follow-up compared to baseline. This reduction in volume appeared to be maintained for more than six months. Participant concerns were significantly reduced and their wellbeing significantly increased. No serious adverse effects were reported. CONCLUSIONS: RLD may be a useful intervention for BCRL although the results could not be attributed to the reflexology intervention because of research design limitations. The main conclusion was, however, that there was sufficient evidence for further research using a randomized controlled trial.

Glucose homeostasis and safety in patients with acromegaly converted from long-acting octreotide to pegvisomant.

CONTEXT: In clinical practice, patients with acromegaly may be switched from therapy with long-acting somatostatin analogs to pegvisomant. The effect of changing therapies on glucose homeostasis and safety has not been reported. OBJECTIVES: The objectives of this study were to monitor changes in IGF-I levels, glycemic control, and safety, particularly liver function and tumor size. DESIGN: This was a multicenter, open-label, 32-wk trial study. SETTING: The study was performed at outpatient clinics. PATIENTS: Fifty-three patients with acromegaly previously treated with octreotide long-acting release (LAR) participated in this study. INTERVENTION: Pegvisomant (10 mg/d) was initiated 4 wk after the last dose of octreotide LAR and was adjusted based on serum IGF-I concentrations at wk 12, 20, and 28. MAIN OUTCOME MEASURES: The main outcome measures were changes in IGF-I, glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose, and safety during the first 12 wk after conversion. RESULTS: At the end of pegvisomant treatment, IGF-I was normalized in 78% of patients. At wk 32, median fasting glucose concentration and HbA1c were reduced (-1.4 mmol/liter and -0.4%, respectively; both P < or = 0.0001) in the study population. Improvements in glycemic control occurred in patients with normal IGF-I concentrations at wk 4 [n = 15; fasting glucose, -1.7 mmol/liter (P < or = 0.0001); HbA1c -0.2% (P = 0.03)]. Decreases in fasting glucose and HbA1c levels were observed in patients with and without diabetes. HbA1c was reduced by more than 1.0% in patients with diabetes. Median pituitary tumor volume did not change, although tumor volume increased in two patients with macroadenomas. CONCLUSIONS: Conversion from octreotide LAR to pegvisomant was safe and well tolerated. Improved glycemic control indicates that pegvisomant should be considered in patients with acromegaly and diabetes.

Expression of phosphorylated p27(Kip1) protein and Jun activation domain-binding protein 1 in human pituitary tumors.

The cyclin-dependent kinase inhibitor p27(Kip1) (p27) plays a pivotal role in controlling cell proliferation during development and tumorigenesis. p27 has been implicated in pituitary tumorigenesis in studies of knockout mice and in analyses of human pituitary tumor samples. In this study, we further explored the role of p27 in human pituitary tumors by measuring levels of phosphorylated p27 (P-p27), and also Jun activation domain-binding protein 1 (Jab1), which is thought to facilitate the phosphorylation and degradation of p27, in normal pituitary tissue (n = 21), pituitary adenomas (n = 75), and pituitary carcinomas (n = 10). The amount of p27 protein in corticotroph adenomas and pituitary carcinomas was much lower than that in normal pituitary tissue or other types of pituitary adenoma. Nuclear P-p27 protein levels were significantly decreased in the adenomas, compared with the normals, and were much lower in the carcinomas, compared with either normal pituitary tissue or pituitary adenomas. However, P-p27 levels in corticotroph adenomas were similar to normal pituitary tissue, thus demonstrating a greatly increased ratio of P-p27 to p27 specifically in corticotroph tumors. No difference was found in Jab1 protein levels in either corticotroph tumors or other pituitary adenomas, compared with normal tissue, but there was a small but significant increase in Jab1 levels in carcinomas. Corticotroph and metastatic tumors both showed a significantly higher Ki-67 labeling index than normal pituitary or other types of pituitary adenomas, and in general the Ki-67 labeling index was negatively correlated with p27 nuclear staining. The amount of p27 and Jab1 mRNA was positively correlated in all pituitary samples studied but did not correlate with the changes in immunostaining. Our findings suggest that in corticotroph tumors there is an accentuated phosphorylation of p27 into P-p27, possibly related to increased cyclin E expression, whereas both p27 and P-p27 are subject to increased degradation in pituitary carcinomas. Such variations in phosphorylation may play a role in pituitary tumorigenesis, but modulation of Jab1 is unlikely to be important in the pathogenesis of pituitary adenomas.

The management of thyroid cancer in adults: a review of new guidelines.

The management of thyroid cancer has been facilitated by the recent publication of the Guidelines for the management of thyroid cancer in adults under the auspices of the British Thyroid Association and the Royal College of Physicians. This is a consensus document that has been developed by a number of key investigators in the field. The central tenet of the guidelines is that thyroid cancer is a disease which requires specialist care from a multidisciplinary team, including an endocrinologist, nuclear medicine physician, thyroid surgeon and endocrine pathologist. The guidelines are comprehensive and detailed, covering differentiated (papillary and follicular) and medullary cancer of the thyroid. They have been written in sections aimed at thyroid cancer specialists, primary care physicians, patients and their families. The guidelines are greatly welcomed and represent a major step forwards in the co-ordination of specialist care for thyroid cancer in the UK.

Prevalence of visits to massage therapists by the general population: a systematic review.

OBJECTIVE: To systematically review 12-month prevalence of visits to massage therapists by representative samples of the general population across countries. METHODS: Surveys reporting estimates of overall CAM use were included. Studies were identified via database searches. Study quality was assessed using a six-item tool. RESULTS: Twenty-two surveys across six countries were included. Estimates for 12-month prevalence of visits to massage therapists by adults ranged from 0.4% to 20% and the median was 5.5%. Estimates for children were 0.3%-3.8% (median 0.7%), while estimates for older adults were 1.5%-16.2% (median 5.2%). 16 surveys (73%) met at least four of six quality criteria. CONCLUSIONS: This review summarises 12-month prevalence of visits to massage therapists in six countries (USA, UK, Canada, Australia, Singapore and South Korea). A small but significant percentage of these general populations visit massage therapists each year.

Prevalence of visits to five types of complementary and alternative medicine practitioners by the general population: a systematic review.

OBJECTIVE: To systematically review surveys of 12-month prevalence of visits to complementary and alternative medicine (CAM) practitioners for five therapies: acupuncture, homeopathy, osteopathy, chiropractic, and medical herbalism. METHODS: Studies were identified via database searches to 2011. Study quality was assessed using a six-item tool. RESULTS: Forty-one surveys across 12 countries were included. Twenty-five (61%) met four of six quality criteria. Prevalence of visits by adults were (median, range): acupuncturists 1.4% (0.2-7.5%, N = 27 surveys), homeopaths 1.5% (0.2-2.9%, N = 20 surveys), osteopaths 1.9% (0.2-4.4%, N = 9 surveys), chiropractors 7.5% (0.3-16.7, N = 33 surveys), medical herbalists 0.9% (0.3-4.7%, N = 14 surveys). Estimates were slightly lower for children and higher for older adults. There was little change over the past 15-20 years. CONCLUSIONS: This review summarises 12-month prevalence of visits to CAM practitioners in Europe, North America, Australia, East Asia, Saudi Arabia and Israel. A small but significant percentage of these general populations visit CAM practitioners each year.

Improvement in insulin sensitivity without concomitant changes in body composition and cardiovascular risk markers following fixed administration of a very low growth hormone (GH) dose in adults with severe GH deficiency.

OBJECTIVE: Untreated GH-deficient adults are predisposed to insulin resistance and excess cardiovascular mortality. We showed previously that short-term treatment with a very low GH dose (LGH) enhanced insulin sensitivity in young healthy adults. The present study was therefore designed to explore the hypothesis that LGH, in contrast to the standard GH dose titrated to normalize serum IGF-I levels (SGH), may have differing effects on insulin sensitivity, body composition, and cardiovascular risk markers [lipid profile, C-reactive protein (CRP), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and adiponectin] in adults with severe GH deficiency. PATIENTS AND METHODS: In this 12-month open, prospective study, 25 GH-deficient adults were randomized to receive either a fixed LGH (0.10 mg/day, n = 13) or SGH (mean dose 0.48 mg/day, n = 12), and eight age- and body mass index (BMI)-matched GH-deficient adults acted as untreated controls. Fasting blood samples were collected at baseline and at months 1, 3, 6, 9 and 12. Assessments of insulin sensitivity, using the hyperinsulinaemic euglycaemic clamp technique, and body composition, using dual-energy X-ray absorptiometry, were performed at baseline and at month 12. RESULTS: The LGH decreased fasting glucose levels (P < 0.01) and enhanced insulin sensitivity (P < 0.02), but body composition, nonesterified fatty acid (NEFA) levels and cardiovascular risk markers were unchanged. The SGH did not modify insulin sensitivity, decreased truncal fat mass (P < 0.05), CRP (P < 0.05) and IL-6 (P < 0.05) levels, and increased NEFA levels (P < 0.05). No changes were observed with the untreated controls. CONCLUSION: Our data indicate that, in contrast to the SGH, fixed administration of the LGH enhances insulin sensitivity with no apparent effects on body composition, lipolysis and other surrogate cardiovascular risk markers in adults with severe GH deficiency. Thus, the LGH may potentially be a beneficial replacement dose in reducing type 2 diabetes risk in adults with severe GH deficiency.

Corticotroph carcinoma presenting as a silent corticotroph adenoma.

Malignant pituitary tumours are rare and their pathogenesis is not fully understood. We have performed genetic analyses on tissues arising from a pituitary carcinoma that initially presented as a silent corticotroph adenoma but which failed to respond to repeated, aggressive surgical and medical therapy. Loss of heterozygosity (LOH) of known or putative tumour suppressor genes (TSG) was assessed by microsatellite analysis of microdissected tumour and matched patient blood DNA. Clonality of the pituitary tumour samples was analysed by two PCR-based techniques; one employing the highly polymorphic short tandem repeat (STR) within the human androgen receptor allele (HUMARA), another based on a restriction fragment length polymorphism of the X chromosome phosphoglycerokinase (PGK-1) gene. Screening with 9 microsatellite markers demonstrated allelic loss at 3 sites (D1S190, D3S1283 and D10S297) in all tumour samples except the presenting pituitary tumour. X chromosome inactivation analysis demonstrated polyclonality in the original presenting tumour and a metastatic deposit but monoclonality in tissue samples from a second and third transsphenoidal resection. In these cases of tumour recurrence both LOH and X chromosome inactivation suggest that monoclonality arose from preferential clonal growth from the original polyclonal tumour. Polyclonality of the metastatic deposit suggests that this was derived from the presenting tumour, although the LOH pattern indicates that a single clone dominates. The data are consistent with increasing allelic loss associated with tumour dedifferentiation and malignant transformation.