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Biomedical subjects

Chi-Sen Chang

Publications and source records attributed to Chi-Sen Chang.

At least 19 recordsLinked to original sources

Association of antibiotic resistance and higher internalization activity in resistant Helicobacter pylori isolates.

OBJECTIVES: Helicobacter pylori resistance to antibiotics is the main factor for therapy failure, while other features remain largely unknown. The aims of this study are to investigate the relationship of antibiotic resistance and in vitro internalization activity between cure and failure isolates and to determine whether failures are associated with persistence of the same predominant strain. METHODS: Fifty-three isolates from forty-seven patients (cure group, n = 31; failure group, n = 16) receiving one of two lansoprazole-based therapies before and/or after therapy were investigated. Antibiotic susceptibility was determined by Etest. Genotyping was determined by cagA, babA, vacA and RAPD analyses. Target cells of internalization assay were AGS cells. RESULTS: Five of six paired pre- and post-treatment isolates had the same predominant genetic profiles and exhibited similarly high internalization activities. The A2143G point mutation of the 23S rRNA gene conferred clarithromycin resistance. Moreover, increased antibiotic resistance after therapy was found for these five cases. Pre-treatment isolates from the failure group (n = 11) had higher level of internalization activity than those from the cure group (n = 31) (P = 0.00005). Antibiotic-resistant strains were significantly associated with higher internalization activity than were susceptible strains (metronidazole, P < 0.005; clarithromycin, P < 0.005). CONCLUSIONS: Our results suggest that resistant H. pylori strains are associated with antibiotic resistance and superior internalization activity, protecting them against antibiotic treatment.

Anti-Bacterial Agents↗

Changes of soluble CD26 and CD30 levels correlate with response to interferon plus ribavirin therapy in patients with chronic hepatitis C.

BACKGROUND: Clearance of hepatitis C virus (HCV) is attributed to host cellular immune responses, in which T helper cells play a critical role. The purpose of the present paper was therefore to study the serial changes of serum soluble markers released from T helper 1 (Th1) and 2 (Th2) and their correlations with treatment responses in chronic hepatitis C patients receiving interferon-alpha plus ribavirin for 24 weeks. METHODS: Serum markers (soluble CD26 and CD30 levels) of T helper cells were quantified before and 6 months after combination therapy in 33 chronic hepatitis C patients and in 20 healthy controls. RESULTS: Compared to healthy controls, chronic hepatitis C patients had significantly lower serum soluble CD26 levels before (140.4 +/- 63.9 ng/mL vs 200.6 +/- 60.3 ng/mL, P < 0.0001) and after (115.9 +/- 32.9 ng/mL vs 200.6 +/- 60.3 ng/mL, P < 0.0001) combination therapy. The level was even lower in those with non-sustained virologic response (non-SVR; 139.0 +/- 50.9 ng/mL vs 117.7 +/- 40.3 ng/mL, P = 0.039). In contrast, soluble CD30 levels at 6 months after combination therapy were significantly lower in patients with SVR than those with non-SVR (6.4 +/- 3.5 U/mL vs 10.4 +/- 5.4 U/mL, P = 0.021). CONCLUSION: Chronic hepatitis C patients have a weak Th1 response as reflected by lower soluble CD26 levels and the levels are even lower in non-sustained responders. In sharp contrast, downregulation of Th2 response with serial changes of soluble CD30 level is associated with successful treatment of HCV infection.

Adult↗

Abnormal acid reflux in asthmatic patients in a region with low GERD prevalence.

BACKGROUND: A high prevalence of gastroesophageal reflux disease (GERD) in asthmatic patients has been reported from North America and Europe. However, only a few data from Asia are available. This study evaluated the incidence of abnormal gastroesophageal reflux (GER) in asthmatic patients in Taiwan. METHODS: Fifty-six consecutive ambulatory patients with clinically stable asthma (41 men and 15 women; age, 57.7 +/- 12.4 years; range, 24 to 74 years) were evaluated prospectively. All patients underwent esophagogastroduodenoscopy, esophageal manometry, and 24-h esophageal pH monitoring. RESULTS: Twenty-nine patients (51.8%) had abnormal GER, as defined by 24-h esophageal pH monitoring. There were 42 patients without endoscopic evidence of esophagitis, 10 patients with Los Angeles (LA) grade A esophagitis, and 4 patients with LA grade B esophagitis. The esophageal motility function studies revealed 21 patients with normal esophageal motility, 23 patients with ineffective esophageal motility (IEM), and 12 patients with nonspecific esophageal motility disorders other than IEM. Although the lower esophageal sphincter (LES) basal pressure was higher in the patients without GER, the difference was not statistically significant. CONCLUSIONS: Abnormal GER seems to be a clinically significant problem in asthmatic patients in Taiwan. The most common esophageal motility dysfunction is IEM. However, the status of Helicobacter pylori infection plays no role in abnormal GER.

Adult↗

Lower prevalence of Helicobacter pylori infection with vacAs1a, cagA-positive, and babA2-positive genotype in erosive reflux esophagitis disease.

BACKGROUND: Increased prevalence of esophagitis has been recognized in the West. Helicobacter pylori infection, particularly virulent strains, is proposed as a protective factor against the development of gastroesophageal reflux disease. To evaluate the relationship of reflux esophagitis with virulent H. pylori infection, we studied the prevalence of reflux esophagitis among H. pylori-infected and -uninfected patients and the genotype of isolates in Taiwan. METHODS: Patients who had routine physical examination were investigated. The severity of esophagitis was evaluated using the Los Angeles grading system. H. pylori status was assessed by histology, rapid urease test, and bacterial culture. Genotyping of vacA, cagA, and babA2 was determined by polymerase chain reaction (PCR). Risk factors for severe esophagitis were evaluated. RESULTS: Reflux esophagitis was found in 21.2% of 1622 patients. The prevalence of H. pylori infection was found in 33.0% of 276 patients with reflux esophagitis compared with 67.5% of 378 patients with normal esophagus (p < .001). Esophagitis occurred in a significantly lower rate among H. pylori-positive patients with peptic ulcer than those without peptic ulcer. cagA, babA2, and vacAs1a were detected in 100% of 143 isolates. Factors that predicted severe esophagitis included age, gender, and hiatus hernia but not H. pylori infection. CONCLUSIONS: Our study suggests significantly lower incidence of H. pylori infection with the triple-positive virulent genotype in patients with reflux esophagitis in Taiwan.

Adhesins, Bacterial↗

Atropine-induced HRV alteration is not amended by electroacupuncture on Zusanli.

Acupuncture is known to influence autonomic nervous activity. Acupuncture on Zusanli points has been shown to enhance the regularity of gastric myoelectrical activity and accelerate gastric emptying, partly through the vagal pathway, in dogs. The aim of this study was to evaluate whether atropine-induced autonomic nervous alteration, measured by heart rate variability (HRV), could be amended by electroacupuncture on Zusanli points. HRV measurements were recorded in 15 healthy volunteers before, during and after electroacupuncture. Each subject was studied for three sessions in a randomized sequence, which included electroacupuncture on the Zusanli (St 36) points with or without premedication of atropine and placebo stimulation on a non-acupoint. The analysis of low frequency (LF), high frequency (HF) and LF/HF ratios were compared between different sessions. Serum levels of gastrin, motilin and pancreatic polypeptide (PP) levels were also measured. There was an increase in the LF/HF ratio (indicating increased sympathetic activity) during the post-acupuncture period with 2 Hz of electrical stimulation on the Zusanli acupoints. When IV atropine was used immediately before the electroacupuncture, there was a decrease in the LF power and HF power during the acupuncture and post-acupuncture periods. In addition, there was a significant increase in the LF/HF ratio during the acupuncture and post-acupuncture periods. There was a significant decrease in serum PP in the post-acupuncture period after premedication with IV atropine. In conclusion, atropine-induced HRV change might be mediated via the vagal pathway. However, atropine-induced HRV alteration is not amended by electroacupuncture on Zusanli points.

Adult↗

Increased oxidative DNA damage, inducible nitric oxide synthase, nuclear factor kappaB expression and enhanced antiapoptosis-related proteins in Helicobacter pylori-infected non-cardiac gastric adenocarcinoma.

AIM: Several epidemiological studies have demonstrated a close association between Helicobacter pylori (H pylori) infection and non-cardiac carcinoma of the stomach. H pylori infection induces active inflammation with neutrophilic infiltrations as well as production of oxygen free radicals that can cause DNA damage. The DNA damage induced by oxygen free radicals could have very harmful consequences, leading to gene modifications that are potentially mutagenic and/or carcinogenic. The aims of the present study were to assess the effect of H pylori infection on the expression of inducible nitric oxidative synthase (iNOS) and the production of 8-hydroxy-deoxyguanosine (8-OHdG), a sensitive marker of oxidative DNA injury in human gastric mucosa with and without tumor lesions, and to assess the possible factors affecting cell death signaling due to oxidative DNA damage. METHODS: In this study, 40 gastric carcinoma specimens and adjacent specimens were obtained from surgical resection. We determined the level of 8-OHdG formation by HPLC-ECD, and the expression of iNOS and mechanism of cell death signaling (including nuclear factor-kappaB(NFkappaB), MEKK-1, Caspase 3, B Cell lymphomal leukemia-2 (Bcl-2), inhibitor of apoptosis protein (IAP) and myeloid cell leukemia-1 (Mcl-1)) by Western-blot assay. RESULTS: The concentrations of 8-OHdG, iNOS, NFkappaB, Mcl-1 and IAP were significantly higher in cancer tissues than in adjacent non-cancer tissues. In addition, significantly higher concentrations of 8-OHdG, iNOS, NFkappaB, Mcl-1 and IAP were detected in patients infected with H pylori compared with patients who were not infected with H pylori. Furthermore, 8-OHdG, iNOS, NFkappaB, Mcl-1 and IAP concentrations were significantly higher in stage 3 and 4 patients than in stage 1 and 2 patients. CONCLUSION: Chronic H pylori infection induces iNOS expression and subsequent DNA damage as well as enhances anti-apoptosis signal transduction. This sequence of events supports the hypothesis that oxygen-free radical-mediated damage due to H pylori plays a pivotal role in the development of gastric carcinoma in patients with chronic gastritis.

Adenocarcinoma↗

Effect of Helicobacter pylori infection on intragastric acidity in patients with reflux esophagitis.

BACKGROUND: The effect of Helicobacter pylori infection on intragastric acidity in patients with reflux esophagitis was investigated. METHODS: Esophageal motility and 24-h intragastric acidity were assessed in endoscopy-proven reflux esophagitis patients with ( n = 50) and without ( n = 50) H. pylori infection. RESULTS: Most of the patients had a mild degree of esophagitis. There was no difference in the age, sex, or body mass index (BMI) between patients with and without H. pylori infection. The 24-h intragastric pH monitoring showed less acidity in patients with H. pylori infection than in those without H. pylori infection (median pH, 1.6 +/- 0.3 vs 1.4 +/- 0.1, with vs without H. pylori infection; P < 0.01). No difference in the patterns of esophageal motility dysfunction was noted between these two groups of patients. CONCLUSIONS: Patients with reflux esophagitis and H. pylori infection had less intragastric acidity than those without H. pylori infection. However, the extent of acid suppression was insufficient to protect the esophagus from acid injury. In addition, the degree of esophageal motility dysfunction was similar in both groups. Therefore, H. pylori infection may play no role in the pathogenesis of reflux esophagitis.

Aged↗

Colonic transit time in long-term dialysis patients.

BACKGROUND: Constipation is a frequent health concern for long-term dialysis patients. The increased incidence of constipation in long-term dialysis patients is based mainly on self-reported data. Our aim is to investigate this problem objectively by using colonic transit time in long-term hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) patients. METHODS: Segmental and total colonic transit time studies measured by means of radiopaque markers were conducted in 56 HD patients, 63 CAPD patients, and 25 healthy control subjects. Segmental colonic transit times were calculated separately for 3 segments of the colon (right, left, and rectosigmoid) and total transit time, which was the sum of all 3 segment times. RESULTS: Colonic transit time was significantly prolonged in HD patients (43.0 +/- 22.2 versus 32.7 +/- 13.7 hours in CAPD patients and 24.3 +/- 11.9 hours in controls; P < 0.001). Increased colonic transit times in the right and rectosigmoid segments, but not the left segment, contributed to the prolongation in total colonic transit time. Age and interdialytic weight gain correlated well with prolongation of total and segmental colonic transit times in HD patients (P < 0.01). Diabetes and female sex in all groups were associated with longer total and segmental colonic transit times, but this trend was not statistically significant. CONCLUSION: Total, right segmental, and rectosigmoid segmental colonic transit times are prolonged in long-term HD patients compared with CAPD patients and healthy controls. We believe colonic transit time measurement is helpful to tailor therapy because it helps define the pathogenesis of constipation.

Adult↗

Effect of P-glycoprotein and multidrug resistance associated protein gene expression on Tc-99m MIBI imaging in hepatocellular carcinoma.

P-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP) expressions as well as Tc-99m methoxisobutylisonitrile (MIBI) images were assessed in 25 patients hepatocellular carcinoma (HCC). Tc-99m MIBI imaging was performed 10 minutes after intravenous injection of 20 mCi Tc-99m MIBI. Using immunohistochemical staining, 60% of the HCC lesions showed positive for Pgp and 64% showed positive for MRP. In 3 patients with MIBI uptake, immunohistochemical study of tumor tissue showed no Pgp stained cells. Nevertheless, they were all positive for MRP. The result of Tc-99m MIBI imaging is more related to the expression of Pgp than MRP gene. It is possible that other membrane transporters as well as Pgp and MRP are involved in the efflux of Tc-99m MIBI.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Long-term follow up of gastric low-grade mucosa-associated lymphoid tissue lymphoma by endosonography emphasizing the application of a miniature ultrasound probe.

BACKGROUND AND AIMS: Endoscopic ultrasonography (EUS) is a useful tool for the evaluation of gastric wall infiltration including gastric lymphoma. The aims of this study were to characterize gastric low-grade mucosa-associated lymphoid tissue (MALT) lymphoma according to EUS findings and to evaluate the role of a miniature ultrasound probe in the long-term follow up. METHODS: From January 1994 to March 2002, 20 patients were proven to have gastric low-grade MALT lymphoma. Endoscopic ultrasonography was performed with a conventional echoprobe and/or a miniature ultrasound probe for initial staging and a miniature ultrasound probe was performed during follow up. All patients positive for Helicobacter pylori received a 2-week course of omeprazole, amoxicillin and clarithromycin. RESULTS: Helicobacter pylori infection was found in 17 (85%) patients. In all patients, H. pylori was eradicated after treatment. Initial EUS showed significantly greater wall thickness (6.1 +/- 3.0 mm) in MALT lymphoma patients when compared with control (2.8 +/- 0.3 mm). The infiltrative patterns included wall thickening (3.5-14.1 mm) in 18 patients: stage E-I1 in 16 (mucosa and/or submucosa), stage E-I2 in one and stage E-II in one. Complete regression of MALT lymphoma following treatment for H. pylori was noted in 14 patients, with a mean duration of 11.3 +/- 9.1 months. Follow-up miniature ultrasound probe sonography showed comparative reduction in wall thickness (P < 0.05). CONCLUSIONS: Endoscopic ultrasonography plays a valuable role in the initial staging and long-term follow up of gastric low-grade MALT lymphoma. The application of a miniature ultrasound probe enables adequate evaluation in the majority of these patients, with additional benefits.

Adult↗

Clinical predictors of large esophagogastric varices in patients with hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, especially in Asia. Gastrointestinal bleeding due to esophagogastric variceal hemorrhage is one of the leading causes of death in HCC patients. The aim of study was to determine whether clinical variables were predictive of the presence of large esophagogastric varices (EGV) before performing endoscopy. Three hundred and four HCC patients who received endoscopy were enrolled and studied retrospectively. Univariate and stepwise logistic regression analysis were used to evaluate associations between the presence of large EGV and patient characteristics. There were 248 patients with small or no EGV and 56 patients with large EGV. The optimal critical values determined by a receiver operating characteristic curve for platelet count and albumin level were 135,000/mm3 and 3.5 g/dl, respectively. Stepwise logistic regression analysis demonstrated that splenomegaly [odds ratio (OR): 9.72; confidence interval (CI): 3.75-25.17], portal vein thrombosis (OR: 2.73; CI: 1.50-4.97), low platelet count (<135,000/mm3) (OR: 3.78; CI: 2.07-6.90) and low albumin level (<3.5 g/dl) (OR: 3.44; CI: 1.73-6.82) were significant, independent predictors for large EGV. Large EGV also could be independently predicted by Child-Pugh classification, splenomegaly (OR: 4.93; CI: 1.87-13.01), or portal vein thrombosis (OR: 2.37; CI: 1.28-4.39) while excluding the non-cirrhotic patients. In conclusion, splenomegaly, low platelet count (<135,000/mm3), and low albumin level (<3.5 g/dl) are clinical predictors to stratify HCC patients at risk of developing large EGV. Besides factors related to liver cirrhosis, portal vein thrombosis is also an important predictor for HCC patients with large EGV.

Carcinoma, Hepatocellular↗

Ineffective esophageal motility is a primary motility disorder in gastroesophageal reflux disease.

The relationship between esophageal motor abnormalities and GERD has been widely studied. The purpose of this study was to identify the prevalence of ineffective esophageal motility (IEM) in patients with GERD. In addition, we also evaluated esophageal acid exposure, acid clearance, and endoscopic esophagitis in GERD patients with IEM. Of 89 patients enrolled in this study, 47 (52.8%) were found to have nonspecific esophageal motility disorder (NEMD). Forty-four of the 47 (93.6%) patients with NEMD met the diagnostic criteria for IEM. The overall incidence of IEM in GERD patients was 49.4%. Patients with IEM had significant increases in upright and recumbent mean fraction of time pH < 4 (6.70% and 4.38%) and mean recumbent esophageal acid clearance (12.45 min/reflux) when compared to those with other motility findings. Seventeen of the 44 (39%) IEM patients did not have endoscopic esophagitis. On the other hand, 26 of the 39 (67%) patients with normal manometry had endoscopic esophagitis. We concluded that not only is the prevalence of IEM high in GERD, but also that IEM patients have more recumbent gastroesophageal reflux and delayed acid clearance. Combined with endoscopic findings, we propose that IEM can be viewed as a specific entity of primary esophageal motility disorder in patients with GERD.

Esophagoscopy↗

Atropine-induced gastric dysrhythmia is not normalized by electroacupuncture.

Acupuncture has been shown to improve the regularity of gastric myoelectric activity. The aim of this study was to evaluate whether atropine-induced gastric dysrhythmia can be normalized by electroacupuncture. Fifteen healthy male volunteers were enrolled for this study. Each subject was studied for three sessions in a randomized sequence which included electroacupuncture on the Zusanli (St 36) points with or without premedication with atropine and a placebo stimulation on a nonacupoint. Cutaneous EGG was performed for 30 min at the baseline, 30 min during acupuncture, and for an additional 30 min after acupuncture. Serum gastrin, motilin, and human pancreatic polypeptide (hPP) levels were also measured. When applying 2 Hz of electrical stimulation on the Zusnali point, there was a significant increase in the percentage of normal frequency (2-4 cpm) during acupuncture (baseline versus acupuncture, 82.09 +/- 12.37% versus 93.08 +/- 8.17%, P < 0.01). There was a significant decrease in the percentage of bradygastria as well as tachygastria during 2 Hz of electrical stimulation on the Zusnali point. Using intravenous atropine immediately before electroacupuncture, the percentage of normal frequency during acupuncture and postacupuncture periods decreased significantly (baselines versus acupuncture and postacupuncture, 83.86 +/- 13.79% versus 55.07 +/- 29.44% and 56.76 +/- 33.44%, P < 0.01). There was a significant decrease in serum PP after intravenous atropine. This observation indicated that atropine-induced gastric dysrhythmia might be mediated partly via the vagal pathway. However, atropine-induced gastric dysrhythmia is not normalized by electroacupuncture.

Adult↗

Mediation of transcatheter arterial chemoembolization induced gastric slow-wave dysrhythmia by endogenous prostaglandin.

BACKGROUND AND AIMS: In recent years, gastric slow-wave dysrhythmias induced by transcatheter arterial chemoembolization (TACE) have been observed. Enhanced endogenous prostaglandin may be a possible mechanism for the myoelectrical changes. The aim of this study was to evaluate whether the gastric slow-wave dysrhythmias induced by TACE may be mediated by ketoprofen, a prostaglandin synthesis inhibitor. METHODS: Twenty-three patients with hepatocellular carcinoma (HCC) admitted for TACE were enrolled. A follow-up TACE was scheduled to take place 2 months later. During the next admission for TACE, 50 mg of ketoprofen was given intramuscularly 12 h for 3 days, beginning 48 h before TACE, as premedication. Cutaneous electrogastrography (EGG) was performed before and within 24 h after TACE. RESULTS: The results showed that the change in the fasting EGG parameters after TACE without premedication was not statistically significant. However, the postprandial EGG parameters, including the dominant frequency (DF); the percentages of DF in the normal, bradygastric and tachygastric range; along with the dominant frequency instability coefficient, deteriorated significantly after the procedure (P < 0.01). After the follow-up TACE with ketoprofen premedication, neither the fasting nor postprandial EGG parameters in the control group changed significantly. CONCLUSIONS: Gastric slow-wave dysrhythmias induced by TACE may be mediated by ketoprofen, a prostaglandin synthesis inhibitor, in HCC patients. However, the improvement in the gastric myoelectrical activity does not eliminate the degree of nausea/vomiting after TACE.

Adult↗

High prevalence of cagA- and babA2-positive Helicobacter pylori clinical isolates in Taiwan.

Two virulence markers, cagA and babA2, were characterized by PCR in 101 Helicobacter pylori isolates from a population in Taiwan. cagA was detected in 99% of the isolates, while babA2 was present in all of the isolates. Base deletions and substitutions at the forward babA2 primer annealing sites were found. Given their high prevalence, cagA and babA2 cannot be useful markers for predicting the high-risk patients of H. pylori infection in Taiwan.

Adhesins, Bacterial↗

Cutaneous electrical stimulation of acupuncture points may enhance gastric myoelectrical regularity.

BACKGROUND/AIM: Cutaneous electrical stimulation has been reported to be as effective as electroacupuncture. The aim of this study was to test whether cutaneous electrical stimulation had the same effect as electroacupuncture to enhance the regularity of myoelectrical activity. METHODS: Fifteen healthy male volunteers were enrolled for this study. Electrogastrography (EGG) was performed for 30 min at the baseline, 30 min during electroacupuncture or cutaneous electrical stimulation, and for an additional 30 min thereafter. RESULTS: During 3 Hz of electroacupuncture on the Zusanli point, there was a significant increase in the percentage of normal frequency. The percentage of normal frequency in the post-acupuncture period was also increased, but it was not statistically significant when compared to the baseline. There was a significant decrease in the tachygastric and bradygastric rhythm during electroacupuncture on the Zusanli points. There were similar changes of EGG parameters with cutaneous electrical stimulation on the Zusanli points. The percentage of normal frequency during cutaneous electrical stimulation increased significantly. However, the percentage of normal frequency in the post-cutaneous electrical stimulation period was similar to the baseline. There was a significant decrease in the percentage of tachygastric rhythm during cutaneous electrical stimulation on the Zusanli points. However, there was no significant change in the percentage of bradygastric rhythm during and after the cutaneous electrical stimulation periods. CONCLUSIONS: The effect of cutaneous electrical stimulation on the percentage of normal frequency and tachygastria is similar to electroacupuncture. Nonetheless, the changes of the percentage in bradygastria are not significant.

Acupuncture Points↗

Hemoperitoneum secondary to spontaneous rupture of metastatic epidermoid carcinoma of liver: case report and review of the literature.

Massive hemoperitoneum due to spontaneous rupture of liver metastasis is remarkably rare. This is of interest because ruptured hepatocellular carcinoma is the most common cause of fatal hemoperitoneum in the Far East. We describe a case of hemoperitoneum secondary to spontaneous rupture of metastatic epidermoid carcinoma of liver. A 60-year-old man with chronic hepatitis C suffered from sudden onset of abdominal pain and pallid face with a tentative diagnosis of hepatocellular carcinoma with rupture. Tumor growth with rupture was suspected based on dynamic computed tomography, but the angiography could not demonstrate the tumor lesion. We diagnosed that the tumor was a metastatic epidermoid carcinoma, of unknown origin, based on the histopathological features. Therapy is palliative rather than curative, and the prognosis is very poor.

Carcinoma, Squamous Cell↗