Predicting postoperative complications and their impact on quality of life and functional status in older patients with breast cancer.

BACKGROUND: The percentage of older patients undergoing surgery for early-stage breast cancer has decreased over the past decade. This study aimed to develop a prediction model for postoperative complications to better inform patients about the benefits and risks of surgery, and to investigate the association between complications and functional status and quality of life (QoL). METHODS: Women aged at least 70 years who underwent surgery for Tis-3 N0 breast cancer were included between 2013 and 2018. The primary outcome was any postoperative complication within 30 days after surgery. Secondary outcomes included functional status and QoL during the first year after surgery, as assessed by the Groningen Activity Restriction Scale and the European Organisation for Research and Treatment of Cancer QLQ-C30 and QLQ-BR23 questionnaires. A prediction model was developed using multivariable logistic regression and validated externally using data from the British Bridging the Age Gap Study. Linear mixed models were used to assess QoL and functional status over time. RESULTS: The development and validation cohorts included 547 and 2727 women respectively. The prediction model consisted of five predictors (age, polypharmacy, BMI, and type of breast and axillary surgery) and performed well in internal (area under curve (AUC) 0.76, 95 per cent c.i. 0.72 to 0.80) and external (AUC 0.70, 0.68 to 0.72) validations. Functional status and QoL were not affected by postoperative complication after adjustment for confounders. CONCLUSION: This validated prediction model can be used to counsel older patients with breast cancer about the postoperative phase. Postoperative complications did not affect functional status nor QoL within the first year after surgery even after adjustment for predefined confounders.

Surgery remains the standard of care for the majority of older patients with breast cancer. The percentage of older patients with breast cancer receiving surgery is decreasing. The reason for this decline is unknown, but it might be due to fear of complications. To better inform patients about the benefits and risks of surgery, the aim of this study was to develop a prediction model for complications after surgery. Another important aspect, especially for older adults with breast cancer, is quality of life, functional capacity, and ability to carry out daily tasks (functional status) after therapy. This study showed that quality of life and functional status did not decline after breast surgery, irrespective of the occurrence of postoperative complications.

Sexual Health Needs: How Do Breast Cancer Patients and Their Partners Want Information?

It is well known that breast cancer treatment can affect sexuality. This survey evaluated the needs of breast cancer patients and partners regarding sexual care. The majority of patients (80.4%) and partners (73.7%) did not receive any information regarding sexuality. Although only a quarter of all respondents reported a direct need for information regarding sexuality, most valued an opportunity to discuss sexuality. The nurse practitioner was the most preferable care provider to provide information about sexuality, supported by a brochure or website. Patients considered during treatment as most suitable timing of discussing sexuality, and partners before the start of treatment.

Enhancing the quality of care for patients with breast cancer: seven years of experience with a Dutch auditing system.

BACKGROUND: Hospitals in the Midwestern part of the Netherlands carried out a clinical audit to monitor the quality of breast cancer care during the years 2002-2008. Compliance with the National Guideline was investigated together with improvement in quality over time. METHODS: Patients with a malignancy of the breast (including ductal carcinoma in situ) participated in this study. Nine quality indicators were evaluated over the years. In 2004 and 2005 the hospitals also carried out an intervention project aimed at improvement of the efficiency of both the diagnostic process and the surgical treatment. RESULTS: At the end of the project all nine indicators showed significant improvement compared to the start of the project. Discussion of treatment strategy in a multidisciplinary breast cancer team took place more often before surgery (83% versus 56%) as well as after surgery (98% versus 70%). The National Guideline for maximum waiting times was met more often for the outpatient clinic (74% versus 61%), time to diagnosis (92% versus 82%), and surgical treatment (52% versus 34%). More sentinel node procedures were performed successfully (92% versus 69%), and for more patients more than 10 lymph nodes were evaluated in case of axillary lymph node dissection (85% versus 58%). More patients had definitive surgical treatment consisting of one surgical intervention (87% versus 75%), and left the hospital within 7 days after hospital admission (98% versus 66%). CONCLUSION: The clinical audit contributed to improvement of the quality of breast cancer care in the Midwestern part of the Netherlands between 2002 and 2008.

Volume- or outcome-based referral to improve quality of care for esophageal cancer surgery in The Netherlands.

Recently, in The Netherlands esophageal resections for cancer are banned from hospitals with an annual volume less than 10. In this study we evaluate the validity of this specific volume cut-off, based on a review of the literature and an analysis of the available data on esophagectomies in our country. In addition, we compare the expected benefits of volume-based referral to the results of a regional centralization process based on differences in outcome (outcome-based referral).

[One hundred years of the Association of Surgeons in the Netherlands. VI. The training]. / Honderd jaar Nederlandse Vereniging voor Heelkunde. VI. De opleiding.

Over the last 25 years the organisation and content of the residency training program for general surgeons have been adapted to meet the needs of changing surgical practice. Recently more profound changes have been dictated by the Dutch Working Hours Act, which has strictly limited the working hours of resident physicians. With this the emphasis will be on improving theoretical and practical training methods. Because of the limiting working hours resident physicians will have a smaller role in patient care. These changes will require a huge effort from both the teaching surgeons and the resident physicians, as well as substantial financial investments from the government and healthcare providers.

Transcriptional control: rheostat converted to on/off switch.

Individual cells translate concentration gradients of extracellular factors into all-or-none threshold responses leading to discrete patterns of gene expression. Signaling cascades account for some but not all such threshold responses, suggesting the existence of additional mechanisms. Here we show that all-or-none responses can be generated at a transcriptional level. A graded rheostat mechanism obtained when either transactivators or transrepressors are present is converted to an on/off switch when these factors compete for the same DNA regulatory element. Hill coefficients of dose-response curves confirm that the synergistic responses generated by each factor alone are additive, obviating the need for feedback loops. We postulate that regulatory networks of competing transcription factors prevalent in cells and organisms are crucial for establishing true molecular on/off switches.

The relative contribution of insulin secretory capacity, insulin action, and incretins to metabolic control after islet transplantation in dogs.

Adequate metabolic control is central to the concept of islet transplantation, but has received limited attention. We studied metabolic control in 8 dogs at 6-9 months after intrasplenic autografting of approximately 25% of the normal mass islets--as compared to 30 controls. A similar posttransplant reduction to approximately 25% of the insulin secretory capacity as assessed by intravenous arginine stimulation during 35 mM glucose clamps, mirrored the reduction of the islet mass. Postprandially, in contrast, the insulin response had increased to 140% in the islet recipients--with a concomitant rise of glycemia to approximately 8.5 mM. Posttransplant, the insulin secretory capacity correlated both with the index of insulin action (which averaged 55% of the normal value) as assessed by euglycemic hyperinsulinemic clamps, and--inverse--with the postprandial glucose excursions. Because insulin action did not correlate with postprandial glucose, the insulin secretory capacity appears to be the primary determinant of the impaired glucose tolerance. Marked postprandial hyperglucagonemia, and a virtually absent pancreatic polypeptide response in the grafted animals, may also have contributed to the impaired glucose tolerance. Posttransplant, infusion of a physiological dose of the gut hormone glucagon-like peptide-1 during 8.5 mM glucose clamps--mimicking the postprandial glycemia--potentiated glucose-stimulated insulin 175%. Thus, after transplantation of a suboptimal islet mass, postprandial glucose excursions are restrained by hyperglycemic potentiation of the entero-insular axis, which may account for the difference in the insulin response to the intravenous and oral challenges. Because, the insulin secretory capacity reflects the islet mass and appears to be the major determinant of glucoregulation, transplantation of a larger islet mass may allow near-normal glycemic control.

Tetracycline-regulatable factors with distinct dimerization domains allow reversible growth inhibition by p16.

Continuous regulation is required to maintain a given cell state or to allow it to change in response to the environment. Studies of the mechanisms underlying such regulation have often been hindered by the inability to control gene expression at will. Among the inducible systems available for regulating gene expression in eukaryotes, the tetracycline (tet) regulatable system has distinct advantages. It is highly specific, non-toxic and non-eukaryotic, and consequently does not have pleiotropic effects on host cell genes. Previously this system also had drawbacks, as it did not extinguish gene expression completely, precluding the study of toxic or growth-inhibitory gene products. We report here the development of a facile reversible tetracycline-inducible retroviral system (designated RetroTet-ART) in which activators and repressors together are expressed in cells. Gene expression can now be actively repressed in the absence of tet and induced in the presence of tet, as we have engineered distinct dimerization domains that allow co-expression of homodimeric tet-regulated transactivators and transrepressors in the same cells, without the formation of non-functional heterodimers. Using this system, we show that growth arrest by the cell cycle inhibitor p16 is reversible and dependent on its continuous expression.

Highly conserved RNA sequences that are sensors of environmental stress.

The putative function of highly conserved regions (HCRs) within 3' untranslated regions (3'UTRs) as regulatory RNA sequences was efficiently and quantitatively assessed by using modular retroviral vectors. This strategy led to the identification of HCRs that alter gene expression in response to oxidative or mitogenic stress. Databases were screened for UTR sequences of >100 nucleotides that had retained 70% identity over more than 300 million years of evolution. The effects of 10 such HCRs on a standard reporter mRNA or protein were studied. To this end, we developed a modular retroviral vector that can allow for a direct comparison of the effects of different HCRs on gene expression independent of their gene-intrinsic 5'UTR, promoter, protein coding region, or poly(A) sequence. Five of the HCRs tested decreased mRNA steady-state levels 2- to 10-fold relative to controls, presumably by altering mRNA stability. One HCR increased translation, and one decreased translation. Elevated mitogen levels caused four HCRs to increase protein levels twofold. One HCR increased protein levels fourfold in response to hypoxia. Although nonconserved UTR sequences may also have a role, these results provide evidence that sequences that are highly conserved during evolution are good candidates for RNA motifs with posttranscriptional regulatory functions in gene expression.

Glucoregulation after canine islet transplantation: contribution of insulin secretory capacity, insulin action, and the entero-insular axis.

The physiological glucoregulatory mechanisms after islet transplantation have been incompletely investigated. We studied the insulin secretory capacity (ISC) by intravenous arginine stimulation during 35-mM glucose clamps, insulin action during hyperinsulinemic euglycemic clamps, and mixed-meal stimulation at 6-9 mo after intrasplenic islet autotransplantation in 8 dogs, as compared with 30 controls. The enteroinsular axis in the recipients was examined by infusion of porcine glucose-dependent insulinotropic polypeptide (GIP) and human glucagon-like peptide-1 (GLP-1) (7-36 amide) under 8.5-mM glycemic clamp conditions in order to mimic the postprandial glycemia after transplantation. The grafts comprised 25% of the native islet mass, and the ISC likewise averaged 25% of the control value. The postprandial insulin response, in contrast, had increased to 140% after transplantation--albeit with a concomitant glucose excursion to approximately 8.5 mM. Insulin action declined on average by 45% posttransplant. The ISC correlated both with the postprandial glucose excursion and insulin action in the grafted dogs. Insulin action did not correlate with the postprandial glucose excursion. Infusion of GIP had no effect, but GLP-1 nearly doubled glucose-stimulated insulin. Thus, a hyperglycemia-enhanced insulinotropic effect of GLP-1, and perhaps other gut hormones, may account for the difference in the insulin response to the intravenous and oral challenges. Because the ISC reflects the engrafted islet mass and appears to be the primary determinant of glucose tolerance, transplantation of higher islet doses should allow prolonged near-normal glucoregulation--at least in the autotransplant setting.

Structure and expression of the murine muscle adenylosuccinate synthetase gene.

A muscle-specific isoform of adenylosuccinate synthetase (AdSS1, EC) is one of three enzymes that constitute the purine nucleotide cycle, a muscle-specific metabolic cycle. Previously, we showed that the muscle Adss1 gene was highly expressed in both skeletal muscle and heart of the adult mouse. Here we have shown that the Adss1 gene is initially activated early in embryonic development in skeletal muscle and heart precursors and is subsequently up-regulated perinatally. The earliest detectable gene expression corresponds with the establishment of the first myogenic and cardiac lineages. To allow identification of the genetic signals controlling this developmental pattern of expression, the Adss1 gene was cloned and its structure determined. Transgenic analysis has shown that 1.9 kilobase pairs of 5' flank can activate expression in skeletal muscle progenitors and direct enhanced expression to adult cardiac muscle. Sequence analysis of the promoter and 5' flanking region revealed the presence of numerous potential muscle-specific cis-regulatory elements.

Function and survival of intrasplenic islet autografts in dogs.

Successful transplantation of isolated islets of Langerhans has been reported in large mammals, including man, but metabolic control has not been well-established. We studied the glucose and islet hormone response to fasting, i.v. glucose bolus infusion, i.v. arginine bolus infusion during a 35-mmol/l hyperglycaemic clamp, mixed meals, and i.v. insulin-induced hypoglycaemia up to 3 years after intrasplenic islet autotransplantation in six pancreatectomised dogs. The individual postprandial insulinogenic index (ratio of 2-h postprandial insulin to glucose levels) at 1 month post-transplant, predicted (r = 0.99) the time to functional graft failure (6-175 weeks). Metabolic studies at 6 months post-transplant in four dogs demonstrated normal fasting glucose and hormone levels, except for reduced pancreatic polypeptide levels. Intravenous glucose and arginine-stimulated insulin were reduced to 15% of preoperative values. In contrast, postprandial normoinsulinaemia was observed--albeit with moderate hyperglycaemia (approximately 10 mmol/l). Postprandial glucagon and glucose-dependent insulinotropic polypeptide (GIP) had increased. Comparison of the post-transplant insulin responses to a meal and to intravenous challenges demonstrated maximal stimulation of the graft by the meal. Post-transplant pancreatic polypeptide responses to a meal and i.v. arginine were severely reduced, and no pancreatic polypeptide response to i.v. insulin-induced hypoglycaemia was observed--indicating absence of cholinergic reinnervation. Thus, glucose regulation and both the insulin secretory capacity and life expectancy of islet grafts were best documented by meal testing. Tentatively, a postprandial hyperglycaemia-enhanced incretin effect of glucose-dependent insulinotropic polypeptide and other gut hormones may account for the difference in the insulin response to i.v. glucose and a meal. Aside from the reduced insulin secretory capacity, both a deranged pulsatile delivery of insulin, hyperglucagonaemia, and pancreatic polypeptide deficiency may have been conducive to glucose intolerance.

Insulinotropic effects of cholecystokinin, gastric inhibitory polypeptide and glucagon-like peptide-1 during perifusion of short-term cultured canine isolated islets.

Recent metabolic studies suggest that the incretin effect of gut hormones may account for most of the circulating insulin during mild postprandial hyperglycemia after transplantation of isolated islets. As yet, however, insulinotropic effects of pharmacological rather than physiological levels of the incretin candidates cholecystokinin-33 (CCK-33), gastric inhibitory polypeptide (GIP), and glucagon-like peptide-1 (GLP-1) on isolated perifused islets have been reported. We examined the insulinotropic effects of these peptides during perifusion of canine isolated islets. Exploration of beta-cell sensitivity in our model with graded 0.1-10 nM doses of CCK-33 and GIP at a 7.5 mM glucose level demonstrated insulinotropic effects from the lowest level. We, therefore, focused on the (near-) physiological effects of both CCK-33 (20 pM), GIP (500 pM), and GLP-1 (100 pM) during perifusion at a 2.5, 7.5, and 10 mM glucose level. No effects of CCK-33 were observed. GIP enhanced insulin release 1.1- and 1.2-fold, at the 7.5 and 10 mM glucose level, respectively. GLP-1 stimulated insulin output from the 2.5 mM glucose level; and a maximum, 2-fold, increase of insulin output was observed from the 7.5 mM glucose level. Thus, isolated perifused islets do respond to near-physiological beta-cell stimulation with gut hormones, and both GIP and GLP-1 may contribute to a hyperglycemia-enhanced activation of the enteroinsular axis after transplantation of isolated islets.

Adenylosuccinate synthetase: a dominant amplifiable genetic marker in mammalian cells.

Adenylosuccinate synthetase (AdSS) functions at the branchpoint of purine nucleotide metabolism leading to the synthesis of AMP. The enzyme is inhibited by a metabolite of alanosine, an aspartic acid analog that is highly cytotoxic for most cells. We show here that it is possible to use alanosine selection to isolate from a population of transformants those cells having the highest levels of AdSS activity resulting from uptake and expression of AdSS minigenes. Transformants isolated in this way were selected for resistance to even higher concentrations of alanosine and resulted in the isolation of cells with highly amplified copies of the transfected AdSS minigenes. We demonstrated that nonselectable genes can be cotransferred and coamplified with AdSS minigenes. These findings indicate that AdSS minigenes can be used as dominant amplifiable genetic markers in mammalian cells.

Cell preservation in University of Wisconsin solution during isolation of canine islets of Langerhans.

Allogeneic islet transplantation in Type I diabetic patients is considerably hampered by the variable outcome of islet isolation and purification. After collagenase digestion of the pancreas, islet isolation is traditionally performed under hypothermic conditions in physiological solutions such as Hanks and RPMI. The University of Wisconsin solution (UWS) has been shown superior for hypothermic preservation of the pancreas. We, therefore, compared the UWS and RPMI for canine islet isolation and subsequent purification in either a conventional hyperosmotic density gradient of dextran in Hanks, or a novel normosmotic density gradient of Percoll in UWS. The isolation solution did not affect islet yield before purification (51% of the native islet mass). Loss of amylase (30%) and swelling of the acinar cells were observed in RPMI. In contrast, no loss of amylase and slight shrinkage of the acinar cells were observed in the UWS. Cell swelling affected the density separation and viability of the cells. Dextran density separation resulted in a 15% purity and 41% recovery of the islets isolated in RPMI, as compared to a 93% purity and 52% recovery of islets isolated in UWS. Percoll density separation improved the purity (99%) and recovery (74%) of islets isolated in UWS. Islets isolated in UWS demonstrated a superior basal and glucose stimulated insulin release during perifusion. Electron microscopy demonstrated a well-preserved islet ultrastructure after isolation in both solutions--except for slightly swollen mitochondria after isolation in RPMI. Autotransplantation of islets in pancreatectomised dogs was successful both after isolation in UWS and RPMI. We conclude that prevention of cell swelling during isolation and purification in the UWS resulted in an improved yield of viable and consistent virtually pure islets. Prevention of cell swelling during islet isolation should facilitate the analysis and control of other factors affecting outcome in man.

Amplification of an adenylosuccinate synthetase gene in alanosine-resistant murine T-lymphoma cells. Molecular cloning of a cDNA encoding the "non-muscle" isozyme.

Adenylosuccinate synthetase (EC 6.3.4.4) catalyzes the initial step in the conversion of IMP to AMP. Two isoforms of this enzyme have been observed in vertebrates. A muscle isozyme is highly abundant in cardiac and skeletal muscle tissue and is thought to play a role in muscle energy metabolism. The non-muscle isozyme, which is present at low levels in most tissues, likely functions in de novo AMP biosynthesis. The analysis of the non-muscle isozyme has been hampered by its low abundance and instability during purification. In this study a genetic selection scheme was used to generate a murine T-lymphoma cell line which was at least 100-fold enriched for the non-muscle isozyme, as a result of amplification of the non-muscle synthetase gene. This cell line made possible the purification of the non-muscle isozyme, and the subsequent isolation of isozyme-specific peptides. Based on peptide sequence information a degenerate oligonucleotide probe was designed and used to screen a mouse kidney cDNA library. A 1.5-kilobase cDNA encoding the non-muscle isozyme was cloned and found to contain an open reading frame of 1368 base pairs encoding 456 amino acids. Gene transfer experiments showed that the cDNA encoded a 50-kDa protein, the size expected for mammalian synthetases, that correlated with the presence of high levels of synthetase activity. The deduced amino acid sequence of the mouse non-muscle synthetase is approximately 75% identical to the previously reported mouse muscle synthetase. Southern blot analysis of mouse genomic DNA with the isozyme-specific cDNA probes revealed that the synthetase isozymes are encoded by separate genes. The non-muscle gene is expressed in most tissues but is virtually undetectable in striated muscle tissues. Three different transcripts (1.7, 2.8, and 3.4 kilobases) are detected for the non-muscle isozyme which show a similar tissue distribution. The availability of a cDNA for the non-muscle isozyme of adenylosuccinate synthetase will facilitate further comparative analyses with the previously cloned muscle isozyme.