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John F Gibbs

Publications and source records attributed to John F Gibbs.

32 records · Page 2Linked to original sources

Contemporary management of benign liver tumors.

Benign lesions of the liver represent diagnostic dilemmas, clinically and radiographically; however, certain clues can help the extensive differential diagnosis of both benign and malignant processes. Hemangiomas and simple cysts have very distinct and very specific radiographic characteristics, and if diagnosed, no further work-up is necessary. The remaining benign lesions have significant overlap, even though there are some more common characteristics to each of the entities. Still, differentiation of any particular lesion outside simple cysts or hemangioma may be difficult. It is reasonable and relatively simple, with minimal invasiveness, to perform US- or CT-guided, percutaneous core-needle biopsies. It is recommended that core biopsies be performed, because many of the benign entities have some overlapping histologic features, and if fine-needle aspirations are performed, a definitive diagnosis may be difficult to obtain. A definitive pathological diagnosis still cannot be made in some cases, even after needle biopsy. Therefore, a surgical resection or wedge resection may be necessary if a benign process cannot be definitively ruled out.

Adenoma, Liver Cell↗

Overexpression of urinary plasminogen activator (uPA) protein and mRNA in thyroid carcinogenesis.

OBJECTIVE: Urinary plasminogen activator (uPA), a protease, is one of the critical components of tumor invasion and metastasis. Its expression in thyroid carcinoma and potential role in thyroid tumorigenesis are unknown. The objective of this study was to determine whether uPA is differentially expressed in benign and malignant thyroid tumors. DESIGN: uPA expression was evaluated by immunohistochemistry (IHC) in 20 thyroid tumors (six classic papillary thyroid cancers (PTC) and three tall cell variants (TCV) and 11 adenomas). To validate IHC results, in situ hybridization was performed on both adenomas and cancer tissues to explore the expression of uPA at the mRNA level. The Fisher exact test was used to compare protein as well as mRNA expressions in adenomas and thyroid cancer. RESULTS: Intense granular cytoplasmic staining for uPA was observed in five of nine (56%) of thyroid cancers: 2/6 classic PTC (33%) and all tall cell variant PTC. Furthermore, uPA mRNA expression was found in the malignant thyroid epithelium but not in adjacent normal thyroid follicles or the stromal elements. None of the adenomas expressed uPA (P = .008). uPA staining was absent in histologically normal follicles adjacent to malignant thyroid follicles. CONCLUSIONS: uPA is expressed in thyroid carcinoma but not in benign adenomas or normal adjacent follicles. The selective expression of uPA in thyroid carcinoma provides evidence that uPA is useful in distinguishing benign and malignant thyroid neoplasms. More importantly, uPA may represent molecular target for therapeutic treatment of this malignancy.

Adenocarcinoma, Papillary↗

Evaluation of urinary plasminogen activator, its receptor, matrix metalloproteinase-9, and von Willebrand factor in pancreatic cancer.

PURPOSE: Pancreatic cancer remains a devastating problem with the majority of patients succumbing to death from this disease. A hallmark of pancreatic cancer is the loss of basement membrane that may be attributed to the action of urinary plasminogen activator (uPA) and matrix metalloproteinase-9 (MMP-9). These enzymes are also implicated in angiogenesis. uPA and microvessel density have been shown to be good prognostic indicators for breast and colon cancer. MMP-9 and microvessel density have not been investigated in pancreatic cancer. We have therefore investigated by immunohistochemistry: (a) frequency of uPA expression and its receptor uPAR and the site of synthesis of uPA by in situ hybridization (ISH); (b) MMP-9 and its coexpression with uPA; (c) microvessel density as determined by von Willebrand factor staining and its relationship to uPA and MMP-9 expression; and (d) correlation of these parameters with survival. EXPERIMENTAL DESIGN: Archival paraffin sections of 27 pancreatic tumors were semiquantitatively investigated by immunohistochemistry using the following antibodies: (a) monoclonal antibodies (MAbs) uPA(1) and uPA(2) (3689 and 394, respectively); (b) MAb uPAR, (no. 3932); (c) MAb MMP-9 (no. 936); and (d) rabbit anti-F8RA/vWF. ISH was performed using a uPA cDNA. RESULTS: Both uPA antibodies revealed overexpression of uPA (93%) often with uniform staining of tumor cells. uPAR and MMP-9 showed focal staining in only 52 and 37% of tumors, respectively. Morphologically normal appearing ductal cells in close proximity to tumors overexpressed uPA in contrast to distally located normal cells (P = <0.001). uPA staining was also investigated in pancreatic intraepithelial neoplasia (PanIN) lesions. PanIN 1A/B staining for uPA was seen in 8 cases (30%), that for PanIN 2 in 19 cases (70%), and for PanIN3 in 12 cases (44%). Lumen of microvessels in the tumor stroma also revealed staining of uPA in 10 cases (37%). ISH experiments revealed the presence of uPA mRNA not only in the cytoplasm of tumor cells but also in adjacent normal appearing ducts as well as in PanIN lesions. Patients with overexpression of uPA, uPAR, or MMP-9 had a trend toward poorer survival than those who did not express it. Microvessel density did not show any significant relationship with uPA, uPAR, and MMP-9 expression and survival. CONCLUSIONS: We conclude that uPA and MMP-9 are potential prognostic indicators in pancreatic cancer, whereas microvessel density may not be one. This study confirms our previous observation that uPA is made by the tumor cells themselves. Presence of uPA in vessels of tumor stroma suggests that uPA is in circulation, and its measurement and that of MMP-9 in the blood of these patients may aid in prognosis. Patients showing overexpression of uPA and MMP-9 have a trend toward shorter survival time.

Biotinylation↗

Regional chemotherapy is indicated after surgical resection of colorectal metastases to the liver: a debate.

Surgical resection for selected patients with hepatic metastases from colorectal cancer can cure approximately one-fourth of these patients. The addition of regional chemotherapy as an attempt to improve this statistic has been extensively investigated in clinical trials. As part of a multidisciplinary educational program, a series of debates on various topics in oncology are held at the Roswell Park Cancer Institute, Buffalo, New York, involving the medical, surgical, and radiation oncology departments. One such debate focused on the use of regional chemotherapy after potentially curative resection of hepatic metastases from colorectal cancer. The representative medical and surgical oncology fellows (N.I.K. and B.P.M.), with guidance from their respective mentors (C.G.L., J.F.G., and N.J.P.), presented concise reviews from the literature arguing for and against the use of regional chemotherapy in this setting. They appear as Parts 1 and 2 in this article. This exercise is purely educational and does not in any way reflect the opinion or the clinical practice of the authors. .

Antineoplastic Combined Chemotherapy Protocols↗

Should adjuvant therapy remain the standard of care for patients with resected adenocarcinoma of the pancreas?

Adenocarcinoma of the pancreas continues to be a formidable disease. In the United States, patients who have had resected disease are generally offered adjuvant chemoradiation. The current National Comprehensive Cancer Network practice guidelines uniformly support this practice. We reviewed seven selected series to evaluate the efficacy of adjuvant therapy for patients who had resected adenocarcinoma of the pancreas. Current evidence-based analysis demonstrates that an adjuvant therapy regimen as a standard of care is lacking. We, therefore, believe that it should be used judiciously because its benefit is confined to only a fraction of patients treated by complete resection (R0); patients with residual microscopic disease (R1) derived negligible benefits. Given the financial constraints and the small effect that current therapies have on this fatal disease, clinicians should concentrate on developing novel therapies and new paradigms to address this age-old problem.

Adenocarcinoma↗

How surgeon age affects surveillance strategies for extremity soft tissue sarcoma patients after potentially curative treatment.

BACKGROUND: The optimal strategy for follow-up of extremity soft tissue sarcoma patients after potentially curative treatment remains unknown. We investigated whether the date of completion of formal surgical training affects choice of surveillance strategy. MATERIALS AND METHODS: The 1,592 members of the Society of Surgical Oncology were asked how often they use 12 separate surveillance modalities during years 1-5 and 10 postsurgery. The motivation underlying follow-up was assessed separately. Repeated-measures analysis of variance was used to compare practice patterns by the year in which the surgeon's formal surgery training was completed, controlling for tumor grade, tumor size, and year postsurgery. RESULTS: Of the 716 respondents, 318 performed surgery and also provided long-term postoperative surveillance for their patients. These respondents were considered evaluable. Erythrocyte sedimentation rate, extremity X ray, and bone scan were the follow-up tests which differed significantly among physician age groups. Surgeons who completed training more than 30 years ago ordered erythrocyte sedimentation rate more frequently (P < 0.001). Surgeons in the 21-30 year category ordered extremity X ray and bone scan more frequently (P < 0.05), but the absolute differences among age groups were quite small. Older surgeons were also significantly more likely to believe that follow-up is clinically worthwhile. CONCLUSIONS: The posttreatment surveillance practice patterns of the members of the Society of Surgical Oncology caring for extremity soft tissue sarcoma patients vary only marginally with the length of time since completion of training. Postgraduate education may be one factor homogenizing surgeon behavior in this important aspect of cancer patient care.

Aging↗

Esophageal resection for carcinoma in patients older than 70 years.

BACKGROUND: A larger number of older patients are presenting as candidates for esophageal resection. An aggressive surgical approach in this population is controversial. METHODS: Four hundred thirteen patients with esophageal cancer who presented to Roswell Park Cancer Institute from 1991 to 1998 were retrospectively reviewed. Clinical data, perioperative details, and postoperative courses were compared for patients older and younger than 70 years. RESULTS: One hundred forty-seven patients (36%) were older than 70 years. Risk factors, clinical symptoms, histology, and stage at presentation were equivalent for both age groups. A higher percentage of patients <70 years were candidates for curative resection. There were no significant differences between groups for estimated blood loss, intraoperative transfusions, length of stay, overall morbidity, or mortality. Only postoperative myocardial infarction and atrial fibrillation were increased in the older group. Excluding stage IV disease, there was a significant and similar improvement in median survival after resection for patients both <70 years and >70 years. CONCLUSIONS: In conclusion, esophageal cancer in older patients warrants surgical resection because the benefit to the patient is the same as it is for younger patients, without a significant increase in operative morbidity or mortality.

Adenocarcinoma↗

Predictive factors associated with long-term survival in patients with neuroendocrine tumors of the pancreas.

BACKGROUND: Neuroendocrine tumors of the pancreas are rare tumors. We identified predictive factors that are associated with long-term survival (> or=5 years). METHODS: Fifty patients with a diagnosis of neuroendocrine tumors of the pancreas were retrospectively evaluated. The following factors were evaluated for disease-specific mortality: age, sex, primary tumor location, functional status, type of primary tumor treatment, presence or absence of liver metastases, timing of liver metastases occurrence, and type of liver metastases treatment. Aggressive treatment of the liver metastases included surgery, chemoembolization, or intrahepatic arterial infusion chemotherapy. RESULTS: Twenty-three patients (47%) had tumor located in the head of the pancreas, and 29 patients (58%) had nonfunctioning tumor. Thirty-nine patients (78%) had liver metastases. The median follow-up for the entire group was 35 months (range,.76-206 months). The median survival for the entire group was 40 months, and the overall 1-, 2-, and 5-year survival rates were 84%, 69%, and 36%, respectively. Factors that had a significant favorable effect on survival included curative resection of the primary tumor, metachronous liver metastases, absence of liver metastases, and aggressive treatment of the liver metastases. CONCLUSIONS: Definitive surgical resection of the primary tumor, absence of liver metastases, metachronous liver metastases, and aggressive treatment of the liver metastases were predictors of long-term survival in patients with neuroendocrine tumors of the pancreas.

Adult↗

High-grade dysplasia within Barrett's esophagus: controversies regarding clinical opinions and approaches.

Barrett's esophagus with high-grade dysplasia is a well-known risk factor for the development of esophageal adenocarcinoma, which has become the predominant form of esophageal cancer in the United States. This review addresses four major fundamental issues that shape our treatment decisions regarding high-grade dysplasia within Barrett's esophagus: (1) the poorly defined natural history of high-grade dysplasia in its progression to adenocarcinoma, (2) the potentially high morbidity and mortality of esophageal resection for high-grade dysplasia, (3) the difficulty in detecting cancer among dysplastic cells during endoscopy, and (4) the controversial role of endoscopic mucosal ablative therapy for high-grade dysplasia. Until there are more accurate surveillance methods, better biochemical or molecular markers in predicting cancerous progression, or more effective minimally invasive methods of treatment, esophagogastrectomy must be considered the standard means of managing patients with Barrett's esophagus and high-grade dysplasia. Regular rigorous systematic surveillance and endoscopic mucosal ablation are alternative treatment options that are available but should be used only under strict conditions. The decision to proceed in a certain direction is quite complex and challenging and ideally requires the feedback of patients who are properly educated about the controversies surrounding this disease.

Adenocarcinoma↗

Intraoperative hepatic lymphatic mapping in patients with liver metastases from colorectal carcinoma.

The survival of patients undergoing liver resection for colorectal metastases is poor in the presence of extrahepatic disease. Therefore identification of periportal and celiac lymph node metastases is central to proper patient selection. In this study we examined the technique of intraoperative hepatic lymphatic mapping with isosulfan blue dye in humans. Intrahepatic dye injection was performed in patients undergoing surgical exploration for colorectal liver metastases. The location of all blue-stained lymphatics and lymph nodes was recorded. All stained and unstained lymph nodes were biopsied for pathologic examination. Thirteen intraoperative lymphatic mapping procedures were performed in 11 patients. A blue-stained lymphatic was visualized in 11 of 13 injections (85%). A blue lymph node was visualized in seven of 13 injections (54%). Three of the seven blue nodes (43%) were not detected by the surgeon before the mapping procedure. There were no complications associated with the intrahepatic dye injections. All biopsied lymph nodes were negative for metastatic tumor. We conclude that intraoperative hepatic lymphatic mapping with isosulfan blue dye is a simple, rapid, and safe technique in humans. It may serve as an adjunct to random lymph node biopsy for the identification of periportal and celiac nodal metastases before liver resection in patients with metastatic colorectal carcinoma.

Biopsy↗

Nuclear survivin expression predicts poor outcome in cholangiocarcinoma.

BACKGROUND/AIMS: Survivin is an anti-apoptotic protein expressed in cancer and may have prognostic value. Our study examined the prognostic role of survivin in biliary cancer. METHODOLOGY: Twenty-four consecutive cases of cholangiocarcinoma were studied. Immunohistochemistry was performed using a monoclonal antibody to survivin. Survivin expression was described as absent or weak and strong. RESULTS: Median age was 68 years (range 40 to 77). There were 16 females and 8 males. SEER (Surveillance, Epidemiology and End Results) staging was local in 2, regional in 15 and distant in 7. Treatments included chemotherapy (n=3), surgery (n=9), combined modality (n=10) or no therapy (n=2). Cytoplasmic and nuclear survivin expression was seen in 13 and 11 patients respectively. Strong cytoplasmic survivin expression was seen in 6 cases and strong nuclear survivin in 4. Patients with strong nuclear survivin had a median survival of 11 months, significantly lower than for patients with weak nuclear survivin expression (20 months, p=0.033). Multivariate analysis using the Cox-proportional hazards model identified 4 important prognostic predictors: nuclear survivin (P=0.022), presence of metastasis (P=0.025), age (P=0.019) and use of combined modality therapy (P=0.006). CONCLUSIONS: Nuclear survivin expression in cholangiocarcinoma may identify those with a poor prognosis.

Adult↗

Aberrant crypt foci.

Colon cancer evolves through epithelial cell deregulation and inappropriate proliferation. These histopathological characteristics are exemplified in the biochemical, immunohistochemical, genetic and epigenetic elements detected within colonic mucosa. Early detection is paramount for the prevention of colon cancer deaths. Aberrant crypt foci (ACF) are thought to be the earliest identifiable neoplastic lesions in the colon carcinogenetic model. The progression of ACF to polyp and, subsequently, to cancer parallels the accumulation of several biochemical alterations and mutations whereby a small fraction of ACF evolve to colon cancer. Recent data indicate that, not uncommonly, some ACF bypass the polyp stage in their carcinogenesis thus reinforcing the importance of their early detection and our understanding of their pathogenesis. Since ACF were first detected in carcinogen-treated mice, research efforts have focused on these microscopically visible lesions both in animal and human models. ACF show variable histological features, characterized by Kudo (20) and, therefore, can be grouped into differing categories by in vivo examination with high-magnification-chromoscopic-colonoscopy (HMCC). As expected, ACF are more frequently detected in distal animal and human colons coinciding with the geographic distribution of colorectal cancer (CRC). Various proteomic (Prot) markers may be altered within ACF suggesting possible prospective pathological changes. These markers include Calreticulin, Transgelin, Serotransferrin, Triphosphate isomerase and Carbonic anhydrase II. Other markers of importance include carcinoembryonic antigen (CEA), B-catenin, placental cadherin (P-cadherin), epithelial cadherin (E-cadherin), inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2) and P16INK4a. Genetic mutations of K-ras, B-Raf APC and p53 have been demonstrated in ACF as well as the epigenetic alterations of CpG island methylation. Genomic instabilities (GI), illustrated by a higher GI Index (GII), microsatellite instability (MSI), loss of heterozygosity (LOH) and defects in mismatch repair (MMR) systems, are also expressed. These transformations may lead to the identification of the earliest pathological features initiating colon tumorigenesis. In this review, the advances in ACF research as precursors of CRCs are highlighted.

Animals↗