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1.
Am Surg ; 88(9): 2302-2308, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35608376

ABSTRACT

BACKGROUND: The potential for prehabilitation programs to impact clinical outcomes is uncertain in abdominal cancer patients due to the short window of time to intervene and the weakened state of the patients. To improve the effectiveness of prehabilitation intervention, a multimodal sports science approach was implemented. METHODS: Prior to cancer-related surgery, 21 patients participated in a 4-week exercise and nutrition prehabilitation program comprised of blood flow restriction exercise (BFR) and a sports nutrition supplement. Retrospective data of 71 abdominal cancer patients who underwent usual preoperative care was used as a comparator control group (CON). At 90 days post-surgery, clinical outcomes were quantified. RESULTS: Prehabilitation was associated with a shorter length of hospital stay (P = .02) with 5.5 fewer days (4.7 ± 2.1 vs 10.2 ± 1.2 days in CON) and decreased incidence of any complications (P = .03). Prehabilitation was not related to incidence of serious complications (P = .17) or readmission rate (P = .59). The prehabilitation group recorded 58% more steps on day 5 after surgery (P = .043). DISCUSSION: A 4-week home-based prehabilitation program composed of BFR training and sports nutrition supplementation was effective in reducing postoperative complications and length of hospital stay in older patients with abdominal cancer.ClinicalTrials.gov Identifier: NCT04073381.


Subject(s)
Neoplasms , Preoperative Care , Aged , Humans , Length of Stay , Neoplasms/surgery , Postoperative Complications/epidemiology , Postoperative Complications/prevention & control , Retrospective Studies
2.
JMIR Perioper Med ; 4(2): e32575, 2021 Dec 30.
Article in English | MEDLINE | ID: mdl-34967752

ABSTRACT

BACKGROUND: Complying with a prehabilitation program is difficult for patients who will undergo surgery, owing to transportation challenges and a limited intervention time window. Mobile health (mHealth) using smartphone apps has the potential to remove barriers and improve the effectiveness of prehabilitation. OBJECTIVE: This study aimed to develop a mobile app as a tool for facilitating a multidisciplinary prehabilitation protocol involving blood flow restriction training and sport nutrition supplementation. METHODS: The app was developed using "Appy Pie," a noncoding app development platform. The development process included three stages: (1) determination of principles and requirements of the app through prehabilitation research team meetings; (2) app prototype design using the Appy Pie platform; and (3) app evaluation by clinicians and exercise and fitness specialists, technical professionals from Appy Pie, and non-team-member users. RESULTS: We developed a prototype of the app with the core focus on a multidisciplinary prehabilitation program with accessory features to improve engagement and adherence to the mHealth intervention as well as research-focused features to evaluate the effects of the program on frailty status, health-related quality of life, and anxiety level among patients awaiting elective surgery. Evaluations by research members and random users (n=8) were consistently positive. CONCLUSIONS: This mobile app has great potential for improving and evaluating the effectiveness of the multidisciplinary prehabilitation intervention in the format of mHealth in future.

3.
Eur J Surg Oncol ; 47(11): 2952-2958, 2021 11.
Article in English | MEDLINE | ID: mdl-34092455

ABSTRACT

INTRODUCTION: The impact of prehabilitation remains controversial due to a short presurgical waiting period and the diminished capacity of the patient population. A strategy to augment and optimize the effectiveness of prehabilitations for abdominal cancer patients may be found in the unlikely field of sport science. We investigated the use of blood flow restriction training and sport nutrition supplementation to augment functional capacity and increase muscle strength in twenty-four abdominal cancer patients awaiting surgery. MATERIALS AND METHODS: The sport science-based program was comprised of blood flow restriction exercise 5 to 6 times per week and a daily sports nutrition supplement containing l-citrulline, creatine monohydrate, and whey protein. RESULTS: After 4 weeks of prehabilitation, 6-min walk test, timed up and go, short physical performance battery, 5-chair stand test and physical component score of quality of life were significantly improved (all p < 0.05). Total body and appendicular lean mass as assessed by dual energy X-ray absorptiometry increased by 0.73 ± 1.04 kg (p = 0.004) and 0.42 ± 0.64 kg (p = 0.006), respectively. Total body fat mass and trunk fat mass decreased (p = 0.004 and p = 0.021). There were no significant changes in hand grip strength, fear of falling, the mental component summary of quality of life, or fasting serum concentrations of myostatin, follistatin, and growth hormone. CONCLUSION: A multimodal prehabilitation program, which encompasses blood flow restriction training and sports nutrition supplements, is both feasible and effective in improving lean mass and physical function in abdominal cancer patients prior to surgery.


Subject(s)
Abdominal Neoplasms/surgery , Blood Flow Restriction Therapy , Dietary Supplements , Muscle Strength/physiology , Preoperative Exercise , Sports Medicine , Aged , Female , Humans , Male , Middle Aged
4.
Am Surg ; 87(3): 473-479, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33047966

ABSTRACT

BACKGROUND: Enhanced recovery after surgery (ERAS) protocols have been shown to decrease length of stay (LOS) and improve patient outcomes in a wide variety of surgical fields; however, barriers exist preventing the implementation of all elements. We hypothesize that a subset of ERAS elements are most influential on LOS and readmission following colorectal surgery. STUDY DESIGN: A retrospective review of 840 patients was performed and their compliance with 24 ERAS components evaluated. Two independent machine-learning statistical algorithms were employed to determine which subset of ERAS elements was most impactful on LOS <3 days and hospital readmission. RESULTS: Increasing compliance with ERAS elements had an inverse linear relationship with LOS. Open (vs minimally invasive) surgery was associated with increased LOS. Early mobilization and multimodal pain management are the elements most protective against increased LOS. Readmissions increase with the number of morphine milligram equivalents (MME)/day. The subset of patients who underwent minimally invasive procedures, had multimodal pain control, and less than 16 MME per day were least likely (23%) to have >3-day LOS. Those patients who underwent an open procedure with less than 15 ERAS elements completed were most likely (84%) to have >3-day LOS. CONCLUSION: While increasing compliance with ERAS protocols and minimally invasive procedures decrease LOS and readmission overall, a subset of components-multimodal pain control, limited opioid use, and early mobilization-was most associated with decreased LOS and readmission. This study provides guidance on which ERAS elements should be emphasized.


Subject(s)
Enhanced Recovery After Surgery/standards , Length of Stay/statistics & numerical data , Patient Readmission/statistics & numerical data , Adult , Aged , Algorithms , Female , Guideline Adherence , Humans , Machine Learning , Male , Middle Aged , Minimally Invasive Surgical Procedures , Outcome and Process Assessment, Health Care , Practice Guidelines as Topic , Retrospective Studies
5.
iScience ; 23(8): 101372, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32745985

ABSTRACT

In a conventional culture of three-dimensional human intestinal organoids, extracellular matrix hydrogel has been used to provide a physical space for the growth and morphogenesis of organoids in the presence of exogenous morphogens such as Wnt3a. We found that organoids embedded in a dome-shaped hydrogel show significant size heterogeneity in different locations inside the hydrogel. Computational simulations revealed that the instability and diffusion limitation of Wnt3a constitutively generate a concentration gradient inside the hydrogel. The location-dependent heterogeneity of organoids in a hydrogel dome substantially perturbed the transcriptome profile associated with epithelial functions, cytodifferentiation including mucin 2 expression, and morphological characteristics. This heterogeneous phenotype was significantly mitigated when the Wnt3a was frequently replenished in the culture medium. Our finding suggests that the morphological, transcriptional, translational, and functional heterogeneity in conventional organoid cultures may lead to a false interpretation of the experimental results in organoid-based studies.

6.
Micromachines (Basel) ; 11(7)2020 Jul 07.
Article in English | MEDLINE | ID: mdl-32645991

ABSTRACT

The regeneration of the mucosal interface of the human intestine is critical in the host-gut microbiome crosstalk associated with gastrointestinal diseases. The biopsy-derived intestinal organoids provide genetic information of patients with physiological cytodifferentiation. However, the enclosed lumen and static culture condition substantially limit the utility of patient-derived organoids for microbiome-associated disease modeling. Here, we report a patient-specific three-dimensional (3D) physiodynamic mucosal interface-on-a-chip (PMI Chip) that provides a microphysiological intestinal milieu under defined biomechanics. The real-time imaging and computational simulation of the PMI Chip verified the recapitulation of non-linear luminal and microvascular flow that simulates the hydrodynamics in a living human gut. The multiaxial deformations in a convoluted microchannel not only induced dynamic cell strains but also enhanced particle mixing in the lumen microchannel. Under this physiodynamic condition, an organoid-derived epithelium obtained from the patients diagnosed with Crohn's disease, ulcerative colitis, or colorectal cancer independently formed 3D epithelial layers with disease-specific differentiations. Moreover, co-culture with the human fecal microbiome in an anoxic-oxic interface resulted in the formation of stochastic microcolonies without a loss of epithelial barrier function. We envision that the patient-specific PMI Chip that conveys genetic, epigenetic, and environmental factors of individual patients will potentially demonstrate the pathophysiological dynamics and complex host-microbiome crosstalk to target a patient-specific disease modeling.

8.
Biochem Biophys Res Commun ; 301(1): 8-12, 2003 Jan 31.
Article in English | MEDLINE | ID: mdl-12535632

ABSTRACT

Hyperphosphatemia and II(o) hyperparathyroidism are common and severe complications of chronic renal failure. Reduced dietary phosphorus has been shown to be an effective treatment in reducing serum phosphate and serum PTH. 2(')-Phosphophloretin inhibited small intestine apical membrane Na(+)/phosphate cotransport and reduced serum phosphate in adult rats. 2(')-PP and phosphoesters of phloretin were tested for inhibition of human small intestine brush border membrane alkaline phosphatase activity and for inhibition of Na(+)-dependent phosphate uptake. The IC(50)'s for inhibition of alkaline phosphatase suggested an order of inhibitory potency of 4-PP > phloretin > 4(')-PP > 2(')-PP. Inhibition of Na(+)-dependent phosphate uptake followed the sequence 2(')-PPz.Gt;4(')-PP > 4-PP > phloretin. These results are consistent with 2(')-PP being a specific inhibitor of human intestinal brush border membrane Na(+)/phosphate cotransport.


Subject(s)
Intestinal Mucosa/drug effects , Microvilli/metabolism , Phloretin/pharmacology , Phosphates/metabolism , Sodium/metabolism , Transport Vesicles/metabolism , Animals , Humans , Intestinal Absorption/physiology , Intestinal Mucosa/metabolism , Molecular Structure , Phloretin/analogs & derivatives , Time Factors
9.
J Clin Endocrinol Metab ; 87(7): 3378-84, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12107253

ABSTRACT

We have investigated the relationships between the rates of muscle protein synthesis and degradation and of transmembrane transport of selected amino acids in leg skeletal muscle of 19 severely burned patients and 18 normal controls in the postabsorptive state. Patients were studied on the 14 +/- 5 postburn day, and their mean burn size was 66% +/- 18% of total body surface area. Methods were based on the leg arteriovenous balance technique in combination with biopsies of the vastus lateralis muscle and infusions of isotopic tracers of amino acids. Net muscle protein breakdown was greater in the patients because of an 83% increase in the rate of muscle protein degradation. The rate of muscle protein synthesis was also increased in the patients but to a lesser extent than protein degradation, i.e. by 50% with the arteriovenous phenylalanine balance technique and by 49% with the direct tracer incorporation method. The absolute values of inward transport of phenylalanine, leucine, and lysine were not significantly different in the two groups. However, the ability of transport systems to take up amino acids from the bloodstream, as assessed by dividing inward transport by amino acid delivery to leg muscle, were 50-63% lower in the patients. In contrast, outward phenylalanine and lysine transport were 40% and 67% greater in the patients than in the controls, respectively. We conclude the primary alteration in muscle protein metabolism is an acceleration of protein breakdown, and the increase in protein synthesis likely is due to increased intracellular amino acid availability as a result of accelerated breakdown. Transmembrane transport in the outward direction is accelerated, presumably to facilitate the export of amino acids from muscle to other tissues. In contrast, transmembrane transport in the inward direction is impaired relatively to the increased delivery of circulating amino acid to skeletal muscle secondary to accelerated blood flow.


Subject(s)
Amino Acids/metabolism , Burns/metabolism , Muscle Proteins/metabolism , Muscle, Skeletal/metabolism , Adolescent , Adult , Biological Transport , Female , Humans , Leg , Lysine/metabolism , Male , Middle Aged , Phenylalanine/metabolism , Postprandial Period/physiology , Reference Values , Severity of Illness Index
10.
J Biol Chem ; 275(41): 32122-8, 2000 Oct 13.
Article in English | MEDLINE | ID: mdl-10913157

ABSTRACT

Although ectopic expression of the cholecystokinin B/gastrin receptor (CCK-BR) is widely reported in human colorectal cancers, its role in mediating the proliferative effects of gastrin1-17 (G-17) on these cancers is unknown. Here we report the isolation of a novel splice variant of CCK-BR that exhibits constitutive (ligand-independent) activation of pathways regulating intracellular free Ca(2+) ([Ca(2+)](i)) and cell growth. The splice variant (designated CCK-BRi4sv for intron 4-containing splice variant) is expressed in colorectal cancers but not in normal colonic mucosa adjacent to the cancer. Balb3T3 cells expressing CCK-BRi4sv exhibited spontaneous, ligand-independent, oscillatory increases in [Ca(2+)](i), whereas cells expressing wild-type CCK-BR did not. Primary cultures of cells isolated from resected colorectal cancers also exhibited a similar pattern of spontaneous [Ca(2+)](i) oscillations. For both Balb3T3 and primary tumor cells, application of G-17 (10 and 200 nm, respectively) caused an increase in [Ca(2+)](i). Selective CCK-BR antagonists blocked the G-17-stimulated Ca(2+) responses but not the spontaneous [Ca(2+)](i) oscillations. Cells expressing CCK-BRi4sv exhibited an increased growth rate ( approximately 2.5-fold), in the absence of G-17, compared with cells expressing wild-type CCK-BR. The selective pattern of expression, constitutive activity, and trophic action associated with CCK-BRi4sv suggest that this variant may regulate colorectal cancer cell proliferation though a gastrin-independent mechanism.


Subject(s)
Calcium Signaling , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Receptors, Cholecystokinin/genetics , Receptors, Cholecystokinin/metabolism , 3T3 Cells , Alternative Splicing/genetics , Amino Acid Sequence , Animals , Base Sequence , Binding, Competitive , Calcium/metabolism , Calcium Signaling/drug effects , Cell Division/drug effects , Cloning, Molecular , Colorectal Neoplasms/metabolism , Female , Gastrins/antagonists & inhibitors , Gastrins/pharmacology , Gene Expression Regulation, Neoplastic , Humans , Introns/genetics , Male , Mice , Molecular Sequence Data , Neoplasm Staging , Receptor, Cholecystokinin B , Receptors, Cholecystokinin/antagonists & inhibitors , Receptors, Cholecystokinin/chemistry , Tumor Cells, Cultured
11.
Clin Sci (Lond) ; 99(3): 189-94, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11787470

ABSTRACT

Glutamine is synthesized primarily in skeletal muscle, and enables transfer of nitrogen to the liver, as well as serving other functions. There is increasing evidence for beneficial clinical effects of glutamine supplementation in critically ill patients. However, the response of endogenous glutamine formation to severe stress is poorly understood. The rates of net protein balance, leucine oxidative decarboxylation, and alanine and glutamine synthesis de novo were determined in leg skeletal muscle of 20 severely burned patients and 19 normal controls in the post-absorptive state. Patients were studied at 14+/-5 days post-burn, and their mean burn size was 66+/-18% of total body surface area. Methods were based on the leg arteriovenous balance technique in combination with biopsies of the vastus lateralis muscle. In the post-absorptive state, patients with severe burns, as compared with healthy control subjects, exhibited accelerated muscle loss (+150%) (i.e. proteolysis minus synthesis) and leucine oxidative decarboxylation (+117%), and depletion of the intramuscular free glutamine pool (-63%). The average rate of glutamine synthesis de novo was decreased by 48%, whereas net alanine synthesis de novo was increased by 174%, in skeletal muscle of burned patients. In conclusion, in severely hypercatabolic burned patients, muscle glutamine formation was suppressed, whereas alanine was the major vehicle for inter-organ nitrogen transport. These changes account for a decreased glutamine availability during prolonged severe stress.


Subject(s)
Burns/metabolism , Glutamine/biosynthesis , Muscle, Skeletal/metabolism , Adult , Alanine/biosynthesis , Amino Acids/blood , Amino Acids/metabolism , Blood Glucose/metabolism , Burns/blood , Female , Humans , Leg , Male , Middle Aged
12.
Diabetes ; 48(5): 949-57, 1999 May.
Article in English | MEDLINE | ID: mdl-10331397

ABSTRACT

We have determined the individual and combined effects of insulin and prior exercise on leg muscle protein synthesis and degradation, amino acid transport, glucose uptake, and alanine metabolism. Normal volunteers were studied in the postabsorptive state at rest and about 3 h after a heavy leg resistance exercise routine. The leg arteriovenous balance technique was used in combination with stable isotopic tracers of amino acids and biopsies of the vastus lateralis muscle. Insulin was infused into a femoral artery to increase the leg insulin concentrations to high physiologic levels without substantively affecting the whole-body level. Protein synthesis and degradation were determined as rates of intramuscular phenylalanine utilization and appearance, and muscle fractional synthetic rate (FSR) was also determined. Leg blood flow was greater after exercise than at rest (P<0.05). Insulin accelerated blood flow at rest but not after exercise (P<0.05). The rates of protein synthesis and degradation were greater during the postexercise recovery (65+/-10 and 74+/-10 nmol x min(-1) x 100 ml(-1) leg volume, respectively) than at rest (30+/-7 and 46+/-8 nmol x min(-1) x 100 ml(-1) leg volume, respectively; P<0.05). Insulin infusion increased protein synthesis at rest (51+/-4 nmol x min(-1) x 100 ml(-1) leg volume) but not during the postexercise recovery (64+/-9 nmol x min(-1) x 100 ml(-1) leg volume; P<0.05). Insulin infusion at rest did not change the rate of protein degradation (48+/-3 nmol x min(-1) 100 ml(-1) leg volume). In contrast, insulin infusion after exercise significantly decreased the rate of protein degradation (52+/-9 nmol x min(-1) x 100 ml(-1) leg volume). The insulin stimulatory effects on inward alanine transport and glucose uptake were three times greater during the postexercise recovery than at rest (P<0.05). In contrast, the insulin effects on phenylalanine, leucine, and lysine transport were similar at rest and after exercise. In conclusion, the ability of insulin to stimulate glucose uptake and alanine transport and to suppress protein degradation in skeletal muscle is increased after resistance exercise. Decreased amino acid availability may limit the stimulatory effect of insulin on muscle protein synthesis after exercise.


Subject(s)
Amino Acids/metabolism , Exercise/physiology , Insulin/pharmacology , Muscle Proteins/metabolism , Muscle, Skeletal/metabolism , Adult , Alanine/metabolism , Amino Acids/blood , Biological Transport , Blood Flow Velocity , Femoral Artery , Glucose/metabolism , Humans , Insulin/administration & dosage , Insulin/blood , Kinetics , Leg/blood supply , Lysine/metabolism , Male , Muscle Proteins/biosynthesis
13.
Am J Surg ; 178(6): 592-9, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10670879

ABSTRACT

BACKGROUND: The majority of patients with primary or metastatic malignancies confined to the liver are not candidates for resection because of tumor size, location, multifocality, or inadequate functional hepatic reserve. Cryoablation has become a common treatment in select groups of these patients with unresectable liver tumors. However, hepatic cryoablation is associated with significant morbidity. Radiofrequency ablation (RFA) is a technique that destroys liver tumors in situ by localized application of heat to produce coagulative necrosis. In this study, we compared the complication and early local recurrence rates in patients with unresectable malignant liver tumors treated with either cryoablation or RFA. PATIENTS AND METHODS: Patients with hepatic malignancies were entered into two consecutive prospective, nonrandomized trials. The liver tumors were treated intraoperatively with cryoablation or RFA; intraoperative ultrasonography was used to guide placement of cryoprobes or RFA needles. All patients were followed up postoperatively to assess complications, treatment response, and local recurrence of malignant disease. RESULTS: Cryoablation was performed on 88 tumors in 54 patients, and RFA was used to treat 138 tumors in 92 patients. Treatment-related complications, including 1 postoperative death, occurred in 22 of the 54 patients treated with cryoablation (40.7% complication rate). In contrast, there were no treatment-related deaths and only 3 complications after RFA (3.3% complication rate, P<0.001). With a median follow-up of 15 months in both patient groups, tumor has recurred in 3 of 138 lesions treated with RFA (2.2%), versus 12 of 88 tumors treated with cryoablation (13.6%, P<0.01). CONCLUSIONS: RFA is a safe, well-tolerated treatment for patients with unresectable hepatic malignancies. This study indicates that (1) complications occur much less frequently following RFA of liver tumors compared with cryoablation of liver tumors, and (2) early local tumor recurrence is infrequent following RFA.


Subject(s)
Catheter Ablation , Cryosurgery , Liver Neoplasms/surgery , Neoplasm Recurrence, Local/epidemiology , Algorithms , Carcinoma, Hepatocellular/surgery , Clinical Trials as Topic , Female , Humans , Liver Neoplasms/secondary , Male , Middle Aged , Prospective Studies
14.
J Biol Chem ; 273(2): 1052-7, 1998 Jan 09.
Article in English | MEDLINE | ID: mdl-9422768

ABSTRACT

Vascular endothelial growth factor (VEGF) is implicated in the angiogenesis of human colon cancer. Recent evidence suggests that factors that regulate VEGF expression may partially depend on c-src-mediated signal transduction pathways. The tyrosine kinase activity of Src is activated in most colon tumors and cell lines. We established stable subclones of the human colon adenocarcinoma cell line HT29 in which Src expression and activity are decreased specifically as a result of a transfected antisense expression vector. This study determined whether VEGF expression is decreased in these cell lines and whether the smaller size and reduced growth rate of antisense vector-transfected cell lines in vivo might result, in part, from reduced vascularization of tumors. Northern blot analysis of these cell lines revealed that VEGF mRNA expression was decreased in proportion to the decrease in Src kinase activity. Under hypoxic conditions, cells with decreased Src activity had a <2-fold increase in VEGF expression, whereas parental cells had a >50-fold increase. VEGF protein in the supernatants of cells was also reduced in antisense transfectants compared with that from parental cells. In nude mice, subcutaneous tumors from antisense transfectants showed a significant reduction in vascularity. These results suggest that Src activity regulates the expression of VEGF in colon tumor cells.


Subject(s)
Colonic Neoplasms/genetics , Down-Regulation , Endothelial Growth Factors/genetics , Genes, src , Lymphokines/genetics , Oligonucleotides, Antisense/genetics , Animals , Cell Hypoxia , Colonic Neoplasms/blood supply , Genetic Vectors , Humans , Immunohistochemistry , Mice , Mice, Nude , Neovascularization, Pathologic/genetics , RNA, Messenger/genetics , Transfection , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
15.
Surg Oncol ; 7(3-4): 125-37, 1998.
Article in English | MEDLINE | ID: mdl-10677164

ABSTRACT

Cancer of the colon and rectum is a significant health problem in the United States. Nearly 50% of the 186,000 patients diagnosed annually with colorectal cancer will eventually die of their disease. Because development of a colorectal carcinoma is most frequently preceded by the development of a well-recognized pre-malignant lesion, screening modalities can significantly impact the incidence and mortality rate of this disease. Population screening employing digital rectal examination, fecal occult blood testing and endoscopic examination of the rectum and colon has been demonstrated to reduce the risk of death from colorectal cancer. Screening regimens should be instituted at an earlier age and with increased frequency for patients in the highest risk categories. Patients who have been treated for a cancer of the colon or rectum should undergo surveillance at regular intervals in an attempt to identify recurrences of disease both in the residual colon and rectum and at distant sites. Most physicians and patients believe that intensive follow-up strategies will afford improved survival and quality of life, however few randomized studies examining the utility of intensive follow-up programs have been performed and the quality of cancer-related follow-up literature is generally poor. Good-quality clinical trials are needed to sort out which tests make a difference in the patient's long-term outcome. The algorithm for surveillance for recurrence in the future may be altered as newer testing modalities are developed.


Subject(s)
Colorectal Neoplasms/diagnosis , Colon/diagnostic imaging , Colonoscopy , Colorectal Neoplasms/diagnostic imaging , Colorectal Neoplasms/etiology , Humans , Neoplasm Recurrence, Local/diagnosis , Occult Blood , Palpation , Radiography , Risk Factors
16.
Ann Surg Oncol ; 4(6): 452-61, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9309333

ABSTRACT

BACKGROUND: Controversy exists as to the treatment regimen necessary to best provide optimal local control for inflammatory breast carcinoma (IBC). This study was conducted to determine if mastectomy combined with radiotherapy offered any advantages over radiotherapy alone in patients with IBC who had been treated with doxorubicin-based combination chemotherapy. METHODS: A retrospective review of 178 women treated for IBC on doxorubicin-based multimodality therapy protocols between January 1974 and September 1993 was performed. Clinical and histologic response to treatment, time to local recurrence, survival, and ultimate control of local disease were analyzed. Kaplan-Meier analysis was used to examine survival and relapse times, and Fisher's exact test was used to test differences in treatment outcomes. Significance was determined at p < or = 0.05. RESULTS: Median follow-up was 89 months (range 22 to 223 months). Locoregional disease persisted in seven patients and recurred in 44 patients who had been rendered disease free at a median time of 10 months. The mortality rate after a local recurrence (LR) was 98%, and all patients but one with LR developed systemic metastases. Response to induction chemotherapy influenced the incidence of LR, and the amount of residual disease found on histologic examination of mastectomy specimens was highly prognostic for local failure. Patients who underwent mastectomy in addition to radiotherapy had a lower incidence of LR than did patients who received radiotherapy alone (16.3% vs. 35.7%, p = 0.015). CONCLUSIONS: The addition of mastectomy to combination chemotherapy plus radiotherapy improved local control in patients with IBC. The addition of mastectomy to chemotherapy plus radiotherapy improved distant disease-free and overall survival in patients with a clinical complete or partial response to induction chemotherapy. Patients who had no significant response to induction chemotherapy received no survival or local disease-control benefit from the addition of mastectomy to their treatment regimen. These patients should be considered for entry into clinical trials of new treatment regimens.


Subject(s)
Adenocarcinoma/therapy , Antibiotics, Antineoplastic/therapeutic use , Breast Neoplasms/therapy , Doxorubicin/therapeutic use , Mastectomy , Adult , Aged , Chemotherapy, Adjuvant , Combined Modality Therapy , Disease-Free Survival , Female , Follow-Up Studies , Humans , Middle Aged , Neoplasm Recurrence, Local , Retrospective Studies , Survival Rate , Treatment Outcome
17.
Surgery ; 122(2): 501-7, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9288158

ABSTRACT

BACKGROUND: The c-src protooncogene encodes a protein tyrosine kinase, pp60c-src, that is a mediator in many signal transduction pathways. One pathway in which pp60c-src protein tyrosine kinase activity is implicated involves regulation of vascular endothelial growth factor (VEGF), an angiogenic factor important to neovascularization of growing tumors. Recently we demonstrated that decreased activity of pp60c-src in colon tumor cells contributes to decreased expression of VEGF. This study examined the relationship between pp60c-src activation, cell density, and VEGF production in a colon tumor cell line. METHODS: Parental HT-29 colon adenocarcinoma cells and stable subclones created by transfection with c-src antisense and sense (control) expression vectors were plated under sparse (2 x 10(4) cells/cm2) and confluent (20 x 10(4) cells/cm2) conditions and grown for 36 hours. Protein and RNA were extracted from cells to determine pp60c-src levels, c-Src tyrosine kinase activity, and VEGF mRNA expression. RESULTS: The pp60c-src kinase activity of HT-29 cells and control sense-transfected clones grown under confluent conditions was increased threefold to fivefold compared with cells grown under sparse conditions. In contrast, the ability of confluent culture conditions to increase pp60c-src activity was blunted in antisense transfectants. By regression analysis, VEGF expression was found to vary directly with pp60c-src levels (r2 = 0.886). CONCLUSIONS: Cell density contributes to the regulation of c-src kinase activity and VEGF expression in HT-29 cells. When the steady-state level of pp60c-src is reduced in antisense transfectants, not only is the steady-state level of VEGF reduced, but the ability of confluence to stimulate pp60c-src activity and VEGF production is too. These data suggest that c-src may be an intermediary of both constitutive and inducible pathways for VEGF production in colon tumor cells.


Subject(s)
Endothelial Growth Factors/biosynthesis , Gene Expression Regulation, Neoplastic , Lymphokines/biosynthesis , Proto-Oncogene Proteins pp60(c-src)/metabolism , src-Family Kinases , Adenocarcinoma , Clone Cells , Colonic Neoplasms , DNA, Antisense , Genetic Vectors , Humans , Kinetics , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-yes , Proto-Oncogene Proteins pp60(c-src)/biosynthesis , RNA, Messenger/biosynthesis , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/metabolism , Regression Analysis , Transcription, Genetic , Transfection , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
18.
Surg Endosc ; 11(7): 729-33, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9214320

ABSTRACT

BACKGROUND: Bipolar radiofrequency ablation (BRFA) is a promising technique with which to treat unresectable primary and metastatic liver tumors. Its effects on normal liver tissue and postoperative liver function, however, are unknown. We performed this study to determine (1) the feasibility of using laparoscopic ultrasound to guide placement of BRFA needle electrodes in the liver and (2) the histopathologic, hepatic biochemical, and systemic hemodynamic responses to BRFA. METHODS: Two BRFA lesions were created in the liver of adult domestic pigs to ablate 8-10% of the normal liver volume. Laparoscopic ultrasound was used to guide creation of one peripheral liver lesion and one central liver lesion (with a major hepatic or portal venous vein branch in the center of the BRFA lesions) in each animal. BRFA of liver tissue was performed by passing 12 W of RF power for 16 min across two 16-gauge active-needle electrodes placed 3 cm apart. RESULTS: All animals survived the procedure without significant hemodynamic alterations during or after BRFA. All animals had a transient elevation in serum transaminase levels that returned to normal within 1 week of the BRFA of liver tissue. Gross and microscopic histopathology of the BRFA lesions revealed 2.0-2.5-cm zones of complete coagulative necrosis around and between the BRFA needle tracks without destruction of major blood vessel walls. CONCLUSIONS: This study demonstrates (1) that laparoscopic ultrasound can be used to guide placement of BRFA needles in the liver and (2) that BRFA produces focal destruction of liver without significant systemic hemodynamic responses or alterations in liver function. Further studies of this technique to ablate malignant liver tumors are ongoing.


Subject(s)
Catheter Ablation , Laparoscopy , Animals , Electrodes , Feasibility Studies , Hemodynamics , Liver/surgery , Liver Function Tests , Swine
19.
Ann Surg Oncol ; 4(3): 264-8, 1997.
Article in English | MEDLINE | ID: mdl-9142389

ABSTRACT

BACKGROUND: p125FAK, pp60C-src, and pp62c-yes are protein tyrosine kinases that function in signaling pathways regulating cell adhesion, migration, and growth. The expression and tyrosine kinase activities of pp60c-src and pp62c-yes, and the expression of p125FAK are increased in colorectal tumor metastases relative to normal mucosa. This study investigates whether differences in the activation of pp60c-src and pp62c-yes in colorectal liver metastases correlated with differences in p125FAK expression and whether prognostic significance could be demonstrated from the extent of expression of p125FAK in metastases. METHODS: Activities of pp60c-src and pp62c-yes were measured in the immune complex kinase assay. Relative levels of p125FAK, pp60c-src, and pp62c-yes were determined by immunoblotting. RESULTS: p125FAK was overexpressed in 29 of 30 colorectal cancer liver metastases (range of two-to 195-fold increase compared with normal mucosa). The degree of overexpression of p125FAK was not a significant prognostic factor in survival. A differential activation of pp60c-src and pp62c-yes in colorectal carcinoma liver metastases was observed. However, overexpression of p125FAK was observed in metastases with either pp60c-src or pp62c-yes activated in colorectal carcinoma liver metastases. CONCLUSIONS: p125FAK overexpression appears to be a marker present in colorectal cancer cells with a metastatic phenotype. Furthermore, p125FAK overexpression is independent of pp60c-src or pp62c-yes activation in human colorectal carcinoma liver metastases.


Subject(s)
Carcinoma/enzymology , Cell Adhesion Molecules/metabolism , Colorectal Neoplasms/pathology , Liver Neoplasms/enzymology , Liver Neoplasms/secondary , Protein-Tyrosine Kinases/metabolism , src-Family Kinases/metabolism , Biomarkers, Tumor , Carcinoma/pathology , Focal Adhesion Kinase 1 , Focal Adhesion Protein-Tyrosine Kinases , Humans , Prognosis , Regression Analysis , Sensitivity and Specificity , Survival Analysis
20.
Surg Endosc ; 11(3): 230-4, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9079598

ABSTRACT

BACKGROUND: A search for alternative methods of abdominal insufflation has been prompted by the fact that CO2 insufflation may cause acidosis, decreased cardiac output, increased systemic vascular resistance, and increased cardiac filling pressures. This study evaluates the safety and the cardiopulmonary effects of helium abdominal insufflation (HAI). METHODS: Thirteen ASA class III and IV patients undergoing laparoscopic procedures were studied in a prospective, nonrandomized protocol using HAI. Cardiopulmonary parameters were measured before and after anesthetic induction and every 30 min during HAI. Abdominal insufflation pressure was initially 10 mmHg and was increased to 15 mmHg after 30 min. All measurements were repeated 15 min after deflation of the abdomen. Changes were evaluated by ANOVA. RESULTS: No significant cardiopulmonary complications were observed. No patient developed hypercarbia or acidosis. Peak inspiratory pressure increased with HAI from 20 +/- 1 to 34 +/- 2 cm H2O (p < 0.0001). Cardiac index decreased (3.35 +/- 0.19 vs 2.37 +/- 0.19 l/min/m2; p = 0.0303) and systemic vascular resistance increased (1,123 +/- 66 vs 1,406 +/- 126 dyne . s/cm5; p = 0.0512) while cardiac filling pressures increased with insufflation to 15 mmHg. CONCLUSIONS: Minimal cardiac and pulmonary aberrations were observed. Helium was safe for abdominal insufflation and may be the insufflating agent of choice in patients with significant cardiopulmonary disease.


Subject(s)
Gastrointestinal Neoplasms/complications , Gastrointestinal Neoplasms/surgery , Heart Diseases/complications , Helium/therapeutic use , Laparoscopy , Lung Diseases/complications , Pneumoperitoneum, Artificial , Adult , Aged , Aged, 80 and over , Female , Helium/pharmacology , Hemodynamics/drug effects , Humans , Male , Middle Aged , Risk
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