Utility and diagnostic accuracy of intraoperative frozen sections in hepato-pancreato-biliary surgical pathology.

BACKGROUND AND PURPOSE: Hepato-pancreato-biliary (HPB) surgeries are one of the most challenging and complex procedures. Intraoperative frozen section (IFS) diagnosis plays a pivotal role in management decisions. Comprehensive large cohort studies evaluating utility of IFS in HPB malignancies are lacking. This study aimed to evaluate the accuracy of frozen section analysis and to analyse discrepancies and impact of IFS on the surgical decisions. PATIENTS AND METHODS: This was a retrospective study of IFS received for the HPB specimens between years 2009 and 2021. The results were compared to the permanent sections to evaluate diagnostic accuracy, sensitivity and specificity. Indications, disagreements and impact on the surgical management were analysed. RESULTS: A total of 1008 specimens were evaluated: bile duct margin (279; 27.7%), gallbladder (203; 20.1%), liver lesions (125 cases; 12.4%), lymph nodes (147; 14.6%), pancreatic margin (120; 11.9%) and deposits (134; 13.3%). IFS were diagnosed as negative for malignancy (805; 79.9%), positive for dysplasia (8; 0.8%), suspicious for malignancy (6; 0.6%) and positive for malignancy (189; 18.8%). The overall diagnostic accuracy was 98.4%, and the discordant rate was 1.6%. The sensitivity, specificity, positive predictive value and negative predictive value were 94.7%, 99.4%, 97.5% and 98.6% respectively. The most important reason of discordant results was technical, followed by interpretational and sampling errors. CONCLUSION: The study demonstrates high diagnostic accuracy (98.4%) of IFS in a large dataset of HPB specimens. This comprehensive analysis apprises of the indications, errors and the impact of IFS diagnosis on subsequent HPB surgical management.

Attenuation of opioid tolerance by ETA receptor antagonist, BQ123, administered intravenously in mice.

OBJECTIVES: Intracerebroventricular injection of endothelin-A receptor antagonist BQ123 potentiates opioid analgesia and reverses analgesic tolerance. This study explores whether these effects can be replicated by injecting BQ123 intravenously. METHODS: Male Swiss-Webster mice were used. Morphine tolerance was induced using 3- or 7-day dosing. Intravenous BQ123 (8 mg/kg) was injected only once on Day 1, 2, 3 or 4 (3-day studies), and on Day 4, 6 or 8 (7-day studies). On Day 4 or 8, respectively, tail-flick and hot-plate latencies were measured following a morphine challenge dose. KEY FINDINGS: Intravenous BQ123 increased the potency and duration of morphine antinociceptive responses. In the 3-day study, the antinociceptive response was unaffected by BQ123 given on Days 1 or 2. BQ123 treatment on Day 3 or 4 (Day 4, BQ123 given 15-min before morphine) significantly potentiated antinociceptive response versus vehicle-treated tolerant mice. In 7-day studies, the antinociceptive response was unaffected by BQ123 given on Day 4. BQ123 given on Day 6 or 8 (Day 8, BQ123 given 15-min before morphine) produced a >100% increase in antinociceptive response versus vehicle-treated tolerant mice for at least 48 h. CONCLUSIONS: Intravenous administration of BQ123 is effective in potentiating morphine analgesia and restoring antinociceptive response in morphine-tolerant mice.

Early Allograft Dysfunction After Live Donor Liver Transplantation: It's Time to Redefine?

BACKGROUND: An ideal definition of early allograft dysfunction (EAD) after live donor liver transplantation (LDLT) remains elusive. The aim of the present study was to compare the diagnostic accuracies of existing EAD definitions, identify the predictors of early graft loss due to EAD, and formulate a new definition, estimating EAD-related mortality in LDLT recipients. METHODS: Consecutive adult patients undergoing elective LDLT were analyzed. Patients with technical (vascular, biliary) complications and biopsy-proven rejections were excluded. RESULTS: There were 19 deaths due to EAD of a total of 304 patients. On applying the existing definitions of EAD, we revealed their limitations of being either too broad with low specificity or too restrictive with low sensitivity in patients with LDLT. A new definition of EAD-LDLT (total bilirubin >10 mg/dL, international normalized ratio [INR] > 1.6 and serum urea >100 mg/dL, for five consecutive days after day 7) was derived after doing a multivariate analysis. In receiver operator characteristics analysis, an AUC for EAD-LDLT was 0.86. The calibration and internal cross-validation of the new model confirmed its predictability. CONCLUSION: The new model of EAD-LDLT, based on total bilirubin >10 mg/dL, INR >1.6 and serum urea >100 mg/dL, for five consecutive days after day 7, has a better predictive value for mortality due to EAD in LDLT recipients.

A review of natural products, their effects on SARS-CoV-2 and their utility as lead compounds in the discovery of drugs for the treatment of COVID-19.

During the COVID-19 pandemic lasting now for well more than a year, nearly 247 million cases have been diagnosed and over 5 million deaths have been recorded worldwide as of November 2021. The devastating effects of the SARS-CoV-2 virus on the immune system lead to the activation of signaling pathways involved in inflammation and the production of inflammatory cytokines. SARS-CoV-2 displays a great deal of homology with other coronaviruses, especially SARS-CoV and MERS-CoV which all display similar components which may serve as targets, namely the Spike (S) protein, the main protease (MPro) which is a chymotrypsin-like protease (CLPro) and RNA-directed RNA polymerase (RdRp). Natural constituents found in traditional herbal medicines, dietary supplements and foods demonstrate activity against SARS-CoV-2 by affecting the production of cytokines, modulating cell signaling pathways related to inflammation and even by direct interaction with targets found in the virus. This has been demonstrated by the application of fluorescence resonance energy transfer (FRET) experiments, assays of cytopathic effect (CPE) and in silico molecular docking studies that estimate binding strength. Glycyrrhizin, flavonoids such as quercetin, kaempferol and baicalein, and other polyphenols are the most common constituents found in Traditional Chinese Medicines that modulate inflammation and cell signaling pathways, and bind viral targets demonstrating valuable effects against SARS-CoV-2. However, the bioavailability of these natural products and their dependence on each other in extracts make it difficult to assess their actual utility in the treatment of COVID-19. Therefore, more can be learned through rational drug design based on natural products and from well-designed clinical trials employing specific doses of standardized combinations.

Strategic approach to minimally invasive necrosectomy for necrotizing pancreatitis: technique, complications and predictors of outcome.

BACKGROUND: Minimally invasive retroperitoneal necrosectomy has been an integral component of 'step-up' approach for infected pancreatic necrosis. Even though the clinical outcome of nephroscopic necrosectomy has been studied earlier, its predictor and morbidities following surgery have not been extensively evaluated. We aimed to evaluate the clinical outcome and early and late complications after percutaneous nephroscopic necrosectomy (PCNN). METHODS: The pre- and intra-operative as well as post-operative and follow-up data of severe pancreatitis patients undergoing PCNN were collected prospectively. RESULTS: Out of 115 patients requiring intervention, 40 patients (34.78%) improved with percutaneous drain alone and another 40 proceeded for PCNN. After exclusion, 37 patients successfully underwent 48 sessions of PCNN. Median number of PCNN session was 1 (1-4). Early complications were seen in 21 (56.75%) patients and mortality was experienced in eight (21.62%) patients. On median follow-up of 36 months, 12 (32.43%) patients experienced late complications. Persistent post-operative pancreatic fistula was observed in six (16.21%) patients. Of these, three developed late-onset pseudocyst, whereas one patient had disconnected duct syndrome. Seven patients experienced new-onset diabetes. Age, severity of pancreatitis, preoperative organ failure and multiorgan failure were significant predictors of mortality on univariate analysis (P ≤ 0.05 for each). The logistic regression analysis revealed presence of multiorgan failure before surgery as the sole predictor (P = 0.007; odds ratio 10.417; 95% confidence interval 1.759-61.672). CONCLUSION: Preoperative multiorgan failure was the most important predictor of mortality following PCNN. Late complications were seen in nearly one-third of patients emphasizing the need for long-term follow-up.

Understanding the binding interaction between phenyl boronic acid P1 and sugars: determination of association and dissociation constants using S-V plots, steady-state spectroscopic methods and molecular docking.

Continuous monitoring of glucose and sugar sensing plays a vital role in diabetes control. The drawbacks of the present enzyme-based sugar sensors have encouraged the investigation into alternate approaches to design new sensors. The popularity of fluorescence sensors is due to their ability to bind reversibly to compounds containing diol. In this study we investigated the binding ability of phenyl boronic acid P1 for monosaccharides and disaccharides (sugars) in aqueous medium at physiological pH 7.4 using steady-state fluorescence and absorbance. P1 fluorescence was quenched due to formation of esters with sugars. Absorbance and fluorescence measurements led to results that indicated that the sugars studied could be ordered in terms of their affinity to P1, as stated: sucrose > lactose > galactose > xylose > ribose > arabinose. In each case, the slope of modified Stern-Volmer plots was nearly 1, indicating the presence of only a single binding site in boronic acids for sugars. Docking studies were carried out using Schrodinger Maestro v.11.2 software. The binding affinity of phenyl boronic acid P1 with periplasmic protein (PDB ID 2IPM and 2IPL) was estimated using GlideScore.

Stigma among healthcare workers towards hepatitis B infection in Bangalore, India: a qualitative study.

BACKGROUND: With about 50 million people infected with hepatitis B (HBV) in India the burden of disease is high. Stigma has been identified to have a major negative impact on screening, diagnosis and treatment of hepatitis B patients. The aim of this study was to assess the stigma in nurses and physicians in Bangalore, India; studies on stigma in HBV have only been published outside of India. METHODS: Semi-structured in-depth-interviews were conducted in the period of March 20th and April 16th 2018 to study stigma and other problems in the care of hepatitis B patients. Stigma was pragmatically defined as a mark of disgrace associated with having a hepatitis B infection. Thirty physicians and nurses in different clinics and hospitals across the city of Bangalore were selected by purposeful sampling and snowball effect until theoretical saturation was reached. RESULTS: The following themes were identified during the interviews: feelings when treating a patient; pregnancy and marriage; confidentiality; morality; improvement in care and the difference with HIV. The most stigma was discovered in the theme morality. The majority of our participants mentioned lack of awareness as biggest obstacle in health care of hepatitis B patients. CONCLUSIONS: This is the first qualitative study in India exploring hepatitis B stigma among health care workers. Stigma was found in certain themes, such as morality. Though, no unwillingness to treat was found. There was a general lack of awareness amongst patients according to our participants and could jeopardize proper treatment. These results will further help in developing strategies to tackle hepatitis B in India.

Biodegradation of phenmedipham by novel Ochrobactrum anthropi NC-1.

An Ochrobactrum anthropi bacterial strain named as NC-1, capable of utilizing phenmedipham (PMP) herbicide as the sole of carbon source and energy for growth was isolated from pesticide-contaminated soil sample by enrichment culture technique. The isolated bacterial strain was identified as Ochrobactrum anthropi NC-1 (MH 796134) based on its morphological, cultural, biochemical characteristics and analysis of 16S rRNA gene sequence. The strain NC-1 could degrade more than 98.5% of PMP (2 mM) within 168 h. The optimal degradation pH and temperature were 7.0 and 30-35 °C, respectively. The strain NC-1 degraded PMP by a pathway involving its initial hydrolysis of their central amide carbamate linkage to yield m-aminophenol via methyl-N-(3-hydroxyphenyl) carbamate and m-toluidine were the major intermediates. However, m-aminophenol was not further metabolized, because they neither supported the growth of organism nor stimulated oxygen uptake. But m-toluidine released by dealkylation was followed by hydrolysis. Further, results also revealed that degradation of 4-methyl catechol proceeded via 2-hydroxy-5-methyl-6-oxohexa-2, 4-dienoate through meta cleavage ring processes. The formation of these compounds was confirmed by UV, TLC, HPLC, IR, NMR, and GC-MS spectral analysis. The cell-free extracts of O. anthropi NC-1 grown on PMP contained the activities of PMP hydrolase, toluidine dioxygenase, and 4-methyl catechol 1, 2-dioxygenase. These results demonstrate the biodegradation of PMP and promote the potential use of strain NC-1 to bioremediate PMP-contaminated environment.

Biodegradation of chlorpropham and its major products by Bacillus licheniformis NKC-1.

Chlorpropham [isopropyl N-(3-chlorophenyl) carbamate] (CIPC), an important phenyl carbamate herbicide, has been used as a plant growth regulator and potato sprout suppressant (Solanum tuberosum L) during long-term storage. A bacterium capable of utilizing the residual herbicide CIPC as a sole source of carbon and energy was isolated from herbicide-contaminated soil samples employing selective enrichment method. The isolated bacterial strain was identified as Bacillus licheniformis NKC-1 on the basis of its morphological, cultural, biochemical characteristics and also by phylogenetic analysis based on 16S rRNA gene sequences. The organism degraded CIPC through its initial hydrolysis by CIPC hydrolase enzyme to yield 3-chloroaniline (3-CA) as a major metabolic product. An inducible 3-CA dioxygenase not only catalyzes the incorporation of molecular oxygen but also removes the amino group by the deamination yielding a monochlorinated catechol. Further, degradation of 4-chlorocatechol proceeded via ortho- ring cleavage through the maleylacetate process. 3-Chloroaniline and 4-chlorocatechol are the intermediates in the CIPC degradation which suggested that dechlorination had occurred after the aromatic ring cleavage. The presence of these metabolites has been confirmed by using ultra-violet (UV), high-performance liquid chromatography (HPLC), thin layer chromatography (TLC), Fourier transmission-infrared (FT-IR), proton nuclear magnetic resonance (1H NMR) and gas chromatography-mass (GC-MS) spectral analysis. Enzyme activities of CIPC hydrolase, 3-CA dioxygenase and chlorocatechol 1, 2-dioxygenase were detected in the cell-free-extract of the CIPC culture and are induced by cells of NKC-1 strain. These results demonstrate the biodegradation pathways of herbicide CIPC and promote the potential use of NKC-1 strain to bioremediate CIPC-contaminated environment with subsequent release of ammonia, chloride ions and carbon dioxide.

"No go" donor hepatectomy in living-donor liver transplantation.

BACKGROUND: Selection of appropriate donors after rigorous evaluation is of paramount importance in living-donor liver transplantation. Despite this, donor surgery may not proceed due to unforeseen reasons. The aim of this paper is to study reasons for "no go" donor hepatectomy in living liver donors. PATIENTS AND METHODS: Donor operations stopped after surgical start, directly due to donor safety-related reasons, qualified for inclusion as "no go" donor hepatectomy. Living-donor evaluation was performed as per standard protocol. Data for consecutive living liver donors operated between April 2012 and November 2016 were analyzed to evaluate reasons for "no go" donor hepatectomy in a liver transplantation unit at a tertiary care teaching hospital. RESULTS: In 307 donors, the operation was aborted in 7 (2.3 %). One patient had unexpected biliary pathology with fibrosis found intraoperatively. Operations in five donors were abandoned in view of liver parenchymal abnormalities (fibrosis/steatohepatitis). One donor had hemodynamically significant bradycardia after handling the round ligament. All these donors recovered uneventfully and remained well on follow-up. CONCLUSIONS: "No go" donor hepatectomy remains a real possibility despite rigorous assessment. Although thresholds for on-table rejection of the donor after complete evaluation vary, "no go" hepatectomy is a calculated risk-avoidance approach.

Centhaquin attenuates hyperalgesia and non-evoked guarding in a rat model of postoperative pain primarily through α2B-adrenoceptors.

Centhaquin has been shown to produce antinociception in the mouse hot plate and tail flick assays through the opioid, the α2A and α2B adrenoceptors. Present study was conducted to determine the effects of centhaquin in a rat model of postoperative pain. Involvement of opioid, and adrenergic receptors was assessed by pretreating rats with antagonists at the opioid (naloxone), α2-(atipamezole) or α2B-(imiloxan) adrenergic receptors. Postoperative pain was induced by hind paw plantar incision in male Sprague Dawley rats. Antihyperalgesic effects were determined by measurement of paw withdrawal latencies and withdrawal force, using dynamic von Frey filaments; attenuation of non-evoked guarding was measured by assigning pain scores to spontaneous behaviors. Rotarod test was used to determine motor impairment. Animals received saline, centhaquin or antagonist plus centhaquin. Centhaquin produced dose-dependent antihyperalgesic effect and attenuation of non-evoked guarding behavior, versus saline treated rats (P<0.05). Naloxone partially blocked while atipamezole and imiloxan significantly reversed centhaquin's antihyperalgesic effects (P<0.05). Attenuation of non-evoked guarding behavior was also blocked, but was not statistically significant. Imiloxan produced a greater block compared to atipamezole while naloxone had no significant effect. Rotarod testing indicated that centhaquin did not cause motor impairment. This is the first report demonstrating centhaquin antinociception in the rat postoperative pain model. Opioid, α2 adrenergic, and particularly α2B adrenergic receptors are involved in mediating antihyperalgesia while attenuation of nonevoked guarding is mediated by α2B/α2 adrenergic receptors. Centhaquin could be an effective non-sedating alternative in treating postoperative pain in ambulatory surgeries.

Pharmacokinetics of centhaquin citrate in a dog model.

OBJECTIVES: Centhaquin citrate is a novel agent that is being developed for use in the resuscitation of patients with haemorrhagic shock. While pharmacokinetics have been described in small animal models, the pharmacokinetic parameters of centhaquin citrate in large mammals have yet to be described. METHODS: Four healthy Beagle dogs (two males and two females) were given an intravenous bolus of 1.0 mg/kg centhaquin citrate. Plasma concentrations were measured at baseline and at ten time points within 24 h after administration. Multiple compartmental models were built and compared. The nonparametric adaptive grid function within the Pmetrics package for R was used for parameter estimation. Predicted concentrations were calculated using population mean and individual Bayesian posterior parameters. KEY FINDINGS: Centhaquin citrate pharmacokinetic parameters were best described using a two-compartment model. Median (IQR) values for Ke , Vc , Vp , Kcp and Kpc were 4.9 (4.4-5.2) h(-1) , 328.4 (304.0-331.9) l, 1000.6 (912.3-1042.4) l, 10.6 (10.3-11.1) h(-1) and 3.2 (2.9-3.7) h(-1) , respectively. CONCLUSIONS: Pharmacokinetic parameters of centhaquin citrate in a large mammal have been described. A large volume of distribution and rapid elimination were observed, consistent with previous work in rats.

Neurobiology of opioid withdrawal: Role of the endothelin system.

Morphine and oxycodone are potent opioid analgesics most commonly used for the management of moderate to severe acute and chronic pain. Their clinical utility is limited by undesired side effects like analgesic tolerance, dependence, and withdrawal. We have previously demonstrated that endothelin-A (ETA) receptor antagonists potentiate opioid analgesia and eliminate analgesic tolerance. Mechanistically, G proteins and regulatory proteins such as ß-arrestins have shown to play an important role in mediating opioid tolerance, dependence, and withdrawal. Recently, the involvement of central ET mechanisms in opioid withdrawal was investigated. ETA receptor antagonist was shown to block majority of the signs and symptoms associated with opioid withdrawal. This review focuses on ET as one of the potential novel strategies to manage the challenge of opioid withdrawal. An overview of additional players in this process (G proteins and ß-arrestin2), and the possible therapeutic implications of these findings are presented.

RNTCP in Gujarat: a comparative study between tribal and non-tribal areas.

BACKGROUND: Tribal population resides in difficult to reach terrain. It is vital to know, in context of "Universal care approach", whether they are equitably benefited by RNTCP. OBJECTIVE: To compare RNTCP performance in tribal areas with non-tribal areas and to detect whether the difference in performance indicators is statistically significant. METHODS: A comparative analysis of RNTCP performance indicators like total case detection rate, new smear positive case detection rate, etc., was carried out using annual data of last three years in tribal and non-tribal areas. T-test was applied to confirm statistically significant difference. RESULTS: The performance of tribal area is better in terms of suspects examined per lakh population per year, total case detection rate, NSP case detection rate and success rate. The difference was close to statistically significant difference at 95% confidence limit and the difference was significant at 90% confidence limit. The extra-pulmonary case notification rate was significantly higher in non-tribal areas with understandable reasons. CONCLUSION: Significantly high previously treated smear positive case notification rate in tribal area is a matter of concern. The incentives to tribal areas appear to reap better results and these need to be supported

Synthesis and antinociceptive properties of N-phenyl-N-(1-(2-(thiophen-2-yl)ethyl)azepane-4-yl)propionamide in the mouse tail-flick and hot-plate tests.

The goals of this study, were to synthesize N-phenyl-N-(1-(2-(thiophen-2-yl)ethyl)azepane-4-yl)propionamide (1c) and determine its antinociceptive properties. The effect of clonidine on 1c antinociception and the involvement of opioid, α2-adrenergic, and I2 imidazoline receptors in 1c antinociception were studied. Also examined was the effect of an endothelin ETA receptor antagonist on 1c antinociception. Synthesis of 1c was accomplished in two steps using modifications of previously reported methods. Antinociceptive (tail-flick and hot-plate) latencies were measured in male Swiss Webster mice treated with 1c; antagonists+1c; clonidine+1c; or antagonists+clonidine+1c. Mice were pretreated with naloxone (opioid antagonist), yohimbine (α2-adrenoceptor antagonist), idazoxan (α2-adrenoceptor/I2-imidazoline antagonist), BU224 (I2-imidazoline antagonist) or BQ123 (endothelin ETA receptor antagonist) to study the involvement of these receptors. Compound 1c produced a dose-dependent increase in antinociceptive latencies; ED50 values were 0.15 mg/kg and 0.16 mg/kg, respectively, in the tail flick and hot plate tests. Naloxone, but not yohimbine, idazoxan or BU224, blocked 1c antinociception. Neither clonidine nor BQ123 potentiated 1c antinociception. Results demonstrate that 1c is 15-times more potent than morphine. The antinociceptive effect of 1c is mediated through opioid receptors. The α2-adrenergic, I2-imidazoline and endothelin ETA receptors are not involved in 1c antinociception.

Centhaquin antinociception in mice is mediated by α2A- and α2B- but not α2C-adrenoceptors.

The use of clonidine as a primary and adjuvant analgesic is well-documented. It is known that imidazoline and α2-adrenoceptors are involved in clonidine antinociception. Clonidine also produces antihypertensive actions mediated through the central nervous system. We have reported that centhaquin, a centrally-acting anti-hypertensive drug produces its hypotensive effect through a mechanism of action similar to clonidine. Centhaquin has also been shown to possess significant antinociceptive activity. Centhaquin antinociception is partially blocked by yohimbine, idazoxan, and naloxone; however, the involvement of specific adrenoceptor subtypes (α2A, α2B, or α2C) in centhaquin antinociception is unknown. The present study was conducted to determine antinociceptive properties of centhaquin citrate, a water soluble salt of centhaquin, and involvement of α2A-, α2B-, or α2C-adrenoceptors in centhaquin citrate antinociception in mice. BRL-44408 (α2A-adrenoceptor antagonist), imiloxan (α2B-adrenoceptor antagonist) and JP-1302 (α2C-adrenoceptor antagonist) were used to determine the involvement of α2A-, α2B-, or α2C-adrenoceptors, respectively. Antinociceptive (tail-flick and hot-plate) latencies were determined in male Swiss-Webster mice treated with centhaquin citrate alone and in combination with BRL-44408, imiloxan, or JP-1302. Centhaquin citrate produced significant antinociception in mice (P<0.05) which was unaffected by JP-1302 (P>0.05) but blocked by BRL-44408 (tail-flick test: 49.75% decrease, P<0.05; hot-plate test: 49.12% decrease, P<0.05) and imiloxan (tail-flick test: 46.98% decrease, P<0.05; hot-plate test: 46.42% decrease, P<0.05). This is the first report demonstrating centhaquin citrate antinociception and its blockade by BRL-44408 and imiloxan. We conclude that α2A and α2B but not α2C adrenoceptors are involved in centhaquin antinociception in mice.

Primary adrenal leiomyosarcoma: a case report with immunohistochemical study and review of literature.

Primary adrenal mesenchymal tumors are exceptionally rare. Diagnosis is based entirely on histological and immunohistochemical evaluation which is indispensable not only for determining tumor type but also for predicting biological behavior. We report a rare case of primary leiomyosarcoma of the left adrenal gland, in a 60 year old woman who presented with flank pain. Computed tomography revealed a well defined left adrenal tumor which was surgically resected. Histological examination of the tumor showed malignant spindle cells in interlacing fascicles and whorls. Nuclear pleomorphism, tumor giant cells and abnormal mitotic figures were seen. On immunohistochemistry, the tumor cells showed reactivity for smooth muscle actin, vimentin and desmin; and were negative for cytokeratin, S100 protein, CD117 and HMB-45. A diagnosis of primary adrenal leiomyosarcoma was offered. Postoperative recovery of the patient was uneventful and the patient was symptom free with no evidence of tumor metastasis or recurrence 21 months after surgery.