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Z F Zhang

Publications and source records attributed to Z F Zhang.

At least 73 records · Page 4Linked to original sources
PubMed1997

Methodological issues in the use of tumour markers in cancer epidemiology.

In this chapter, we review major methodological and practical issues associated with the use of tumour markers. At this stage of development, studies with a combination of tumour, susceptibility and exposure markers are needed to illustrate the link between exposure and biological response and to assess the interactive effects of tumour susceptibility markers in this process. Several practical issues related to the application of tumour markers are discussed, including banking of tumour tissue, setting a laboratory strategy and performing etiological heterogeneity analysis.

Biomarkers, Tumor↗
PubMed1997

Smoking history and cancer patient survival: a hospital cancer registry study.

While tobacco use is clearly the most preventable cause of cancer, little is known about whether smoking adversely influences cancer patients' survival. The goal of this study was to examine the effect of smoking history on survival among cancer patients. Data from Memorial Sloan-Kettering Cancer Center's tumor registry was used to identify 25,436 cases of cancer (12,447 male patients and 12,989 female patients). Information regarding smoking and alcohol consumption, histologic grade, tumor stage, and survival time was available. Proportional hazard analysis was used to examine the effect of smoking on the death from all causes among patients. Patients who had a history of smoking were found to have a lower rate of survival than nonsmokers. After controlling for age, race, alcohol use, and histologic grade, the risk ratios were 1.55 for males and 1.43 for females. A dose-response relationship was found between ever-smoking and cancer patient survival. The predictive effect of smoking on survival was significant for patients with oral, pancreatic, breast, and prostate cancers, but not for esophageal, stomach, colon, rectum, laryngeal, lung, cervix uteri, urinary bladder, and kidney cancers. Black patients with oral or breast cancer had a poorer prognosis associated with smoking compared with white and other nonwhite patients. The strongest effect of smoking on survival was found mainly among patients with breast cancer with a distant tumor stage or with prostate cancer with a regional tumor stage. Alcohol use alone was associated with a higher risk of death for nonsmokers with oral and pancreatic cancers than for similar cancer patients without a history of alcohol use. Smoking history plays a critical role in influencing cancer patient survival, especially for patients diagnosed with oral, pancreatic, breast, or prostatic cancers. In addition, alcohol consumption is independently related to survival in patients with oral and pancreatic cancers. Our study suggests that a potential means of improving cancer patient survival, especially from oral, pancreatic, breast, and prostatic cancers, may be achieved through smoking cessation.

Adult↗
PubMed1997

[Studies on epidemiology and etiology of Lyme disease in China].

From 1987 to 1996, an investigation and study on Lyme disease was conducted in sixty counties and districts of twenty-two provinces (autonomous region, municipality). Seroepidemiological findings indicated that some residents from forest areas of twenty-two provinces had a high antibody titer for Borrelia burgdorferi with positive rate 5.06% (1724/34104). Endemic foci of Lyme disease were discovered in seventeen provinces by etiological evidence. Typical cases of Lyme disease were diagnosed in eleven provinces. Prevalence rate of Lyme disease in forest region of northeast China was 1%-4%. Ixodes persulcatus played a leading role in the transmission of Borrelia burgdorferi to human in northern part of China. Ixodes granulatus and Haemaphysalis bispinosa might serve as principal vector of Borrelia burgdorferi in the southern region. Genus apodemus might serve as a major reservoir for B. burgdorferi. A total number of 130 isolates of B. burgdorferi were recovered from patients, ticks or animals. Isolates from China were obviously different from the ones isolated in North America in SDS-PAGE protein profile, plasmid and REA. The analysis of rRNA gene restriction patterns indicated that the Chinese isolates were divided in three genospecies. Genospecies I (B. burgdorferi sensu stricto) was firstly discovered in Asia.

Animals↗
PubMed1997

[Peripheral mechanism of inhibitory effect of centrally administrated histamine on gastric acid secertion].

The present experiment is undertaken to study the peripheral mechanism of the inhibitory effect of intra third ventricular administration of histamine (HA, i.c.v.) on gastric acid secretion. Gastric acid was continuously washed with 37 degrees C saline by means of a perfusion pump in male adrenalectomized SD rats. Drugs were injected intravenously by a syringe pump and their effect on pentagastrin-induced [10 micrograms/(kg.h), i.v.] gastric acid secretion was measured. The results were as follows: (1) The inhibitory effect of HA on gastric acid secretion was abolished by subdiaphragmatic vagotomy. (2) The inhibitory effect of HA on gastric acid secretion could be abolished by pretreatment with atropine [0.05 mg/(kg.100 min), i.v.]. (3) Pretreatment with somatostatin antagonist, cyclo-[7-aminoheptanoyl-Phe-D-Trp-Lys-Thr (Bzl)], [2-4 micrograms/(kg.100 min), i.v.] could also block the inhibitory effect of HA on gastric acid secretion in a dose dependent manner. The above results suggest that the inhibitory effect of centrally administrated HA on gastric acid secretion is mediated by vagi, acetylcholine M receptor and somatostatin.

Adrenalectomy↗
PubMed1997

Expression of cyclin D1, but not cyclins E and A, is related to progression in bilharzial bladder cancer.

The present study was conducted to analyze the alterations affecting cyclins D1, E, and A in bilharzial bladder cancer and to assess their potential clinical significance. A total of 125 cases were examined. Histopathological subtypes included 68 squamous cell carcinomas, 55 transitional cell carcinomas, and 2 adenocarcinomas. Immunohistochemical analyses were performed using a panel of well-characterized antibodies. The results were correlated with proliferative index, as assessed by Ki67 antigen expression. The cyclin D1-positive phenotype, defined as the identification of positive immunoreactivity in the nuclei of >/=20% of tumor cells, was found in 33 of 107 (31%) evaluable cases. A significant association was observed between the cyclin D1-positive phenotype and deep muscle invasion (P = 0.02), high tumor grade (P = 0.02), and Ki67 high proliferative index (P = 0.03). The cyclin E-positive phenotype, defined as per cyclin D1, was found in 79 of 106 (75%) evaluable cases. The cyclin A-positive phenotype, defined using the above criteria, was identified in 60 of 108 (56%) evaluable cases. No statistically significant association was found between cyclins E or A and clinicopathological parameters or proliferative index. However, there was a strong association between the expression of cyclin D1 and the coexpression of cyclins A and/or E (P = 0.05). Ki67 proliferative index was considered high when >/=20% of tumor cells displayed positive nuclear staining, a phenotype that was observed in 99 of 115 (86%) cases. These data support the hypothesis that cyclin D1 activation determines the evolution of a particular subset of aggressive bladder tumors. In addition, cyclins E and A seem to follow an unscheduled pattern of expression, based on the high frequency of identifying a positive phenotype for these cyclins and the lack of correlation between their expression and Ki67 high proliferative index. It may be postulated that the expression of G1 cyclin genes is deregulated in bilharzial bladder cancer, and that cyclin D1 acts as an oncogenic event in these neoplasms. Moreover, the moderate number of tumors displaying the cyclin D1-positive phenotype (31%) versus the high frequency observed for both cyclins E (75%) and A (56%), suggests a short G1 disbalanced by a long S phase and a rapid transversal of the cell cycle, as evidenced by a high Ki67 index observed in 86% of these cases. This imbalance in the cell cycle, together with alterations reported on the p53 pathway, might underline the accumulation of DNA damage and the aggressive clinical course of bilharzial bladder cancer.

Adenocarcinoma↗
PubMed1997

Alterations affecting the p53 control pathway in bilharzial-related bladder cancer.

Bilharzial-related bladder carcinoma (BBC) is the most common malignant neoplasm in Egypt, also occurring with a high incidence in other regions of the Middle East and East Africa. The clinical and pathological features of BBC are different than those described for the conventional transitional cell carcinoma of the bladder, including the high incidence of squamous cell carcinoma reported in BBC and the fact that over 90% of BBC cases at presentation are advanced-stage tumors (P3 and P4). This study was conducted to better define the phenotypic alterations associated with BBC affecting the p53 cell cycle control pathway, including altered patterns of expression of downstream effector proteins such as mdm2 and p21/WAF1. A well-characterized cohort of 125 patients affected with bilharzial-related bladder tumors was studied. Tumors were classified as squamous carcinomas (n = 68), transitional cell carcinomas (n = 55), or adenocarcinomas (n = 2). The products encoded by TP53, mdm2, and p21/WAF1 genes were analyzed by immunohistochemistry. Furthermore, the patterns of expression of these molecules were correlated with the Ki67 proliferative index. In addition, the microanatomical distribution of programmed cell death was assessed in a subset of tumors, using the so-called terminal deoxynucleotidyl transferase-mediated nick end labeling method. p53 nuclear overexpression was identified in 25 (20%) of 125 cases. Nuclear overexpression of mdm2 was detected in 74 (59.2%) of 125 cases. There was a statistically significant association between coexpression of both p53 and mdm2 and detection of lymph node metastases (P = 0.04). p21/WAF1 expression was detected in 87 (72%) of 121 evaluable cases. A high Ki67 proliferative index was observed in 99 (86%) of 115 evaluable cases. There was a statistically significant association between high Ki67 proliferative index and mdm2-positive phenotype (P = 0.005) and deep muscle invasion (P3b; P = 0.026) as well as lymph node metastases (P = 0.039). Apoptosis was observed in terminally differentiated tumor cells identified in the superficial layers of well-differentiated squamous carcinoma or exfoliating cells in transitional lesions. However, only rare apoptotic tumor cells were found in basal or suprabasal layers as well as in the invasive elements of the neoplasms studied. These results suggest that the frequency of p53 nuclear overexpression in BBC is lower than that reported for conventional transitional cell carcinoma. Nevertheless, tumors with p53 alterations have a greater propensity to progress. The prominent number of cases displaying an mdm2-positive phenotype suggests that this may be an early incident in BBC and should be regarded as a potential oncogenic phenomenon. This is supported by the significant correlation between high Ki67 proliferative index and mdm2 overexpression. The association of an aggressive clinical course with the coexpression of both p53 and mdm2 products might be viewed as a cooperative effect that develops in tumor progression.

Adenocarcinoma↗
PubMed1997

Evaluation of the telomeric repeat amplification protocol (TRAP) assay for telomerase as a diagnostic modality in recurrent bladder cancer.

There is a need for the identification of an accurate test for the detection of recurrent bladder cancer. In this study, we evaluate the telomeric repeat amplification protocol (TRAP) assay for detection of telomerase as a potential new method for bladder cancer detection and compare it to voided urine cytology. A urine sample and a bladder wash were obtained from 63 patients with a history of bladder cancer. Cytological evaluation was performed on voided urine, and the TRAP assay was performed on voided urine and bladder wash. The overall clinical sensitivity of the TRAP assay, as defined by the ability to identify correctly the patients with pathologically confirmed bladder cancer, was 35% in voided urine and 50% in bladder wash, whereas the overall clinical sensitivity of voided urine cytology was 71%. The sensitivity of voided urine cytology for the papillary and noninvasive tumors (Ta) was 50%, compared to 92% for the superficially invasive tumors (T1), 62% for the muscle-invasive tumors (T2+), and 100% for the high-grade flat carcinoma in situ (Tis). The clinical sensitivity of the TRAP assay using voided urine was 46% for Ta, 50% for T1, 18% for T2+, and 20% for Tis. The sensitivity of the TRAP assay in Ta disease was similar to that of cytology (50% for cytology versus 46% for the TRAP assay). There was a strong association between the total number of exfoliated malignant cells and the sensitivity of the assay. The sensitivity of the TRAP assay in bladder washes was 44% for Ta, 67% for T1, 46% for T2+, and 43% for Tis. The TRAP assay is reproducible, highly specific, and not dependent on the expertise of the cytopathologist. These results suggest that this assay should be further investigated as a diagnostic tool for bladder cancer.

Carcinoma, Papillary↗
PubMed1996

Metabolic phenotypes of retinoic acid and the risk of lung cancer.

The metabolic activity of cytochrome P-450 enzymes has been associated with an increased risk of developing lung cancer. We found previously that all-trans retinoic acid is catabolized by these oxidative enzymes, and that an inhibitor of this system discriminated between two populations of lung cancer patients. We examined the association between this metabolic phenotype and the risk of lung cancer in 85 subjects. The area under the plasma concentration x time curve (AUC) was calculated after a single oral dose of all-trans retinoic acid (45 mg/m2). The mean AUC for patients who had either squamous or large cell carcinomas was significantly lower than that of patients with adenocarcinomas (P = 0.0001) or control subjects (P = 0.01). Individuals with an AUC < 250 ng x h/ml had a greater likelihood of having squamous or large cell carcinoma (odds ratio = 5.93). This study suggests that the "rapid" catabolism of all-trans retinoic acid is linked to an increased risk of squamous or large cell cancers of the lung.

Adenocarcinoma↗
PubMed1996

Microsatellite instability and deletion analysis of chromosome 10 in human prostate cancer.

Despite the clinical relevance of prostate cancer, few aspects regarding the molecular alterations involved in the process of prostate carcinogenesis are clearly understood. Cytogenetic and molecular genetic studies have identified specific abnormalities in prostate tumors, mainly on chromosomes 8, 10 and 16. On the basis of these findings, we designed a study to further characterize the altered regions on chromosome 10, using 15 microsatellite markers on a population composed of 20 paired normal and primary non-metastatic prostatic-tumor samples. Overall, 65% (13/20) of the cases analyzed showed molecular alterations, mainly rearrangements and deletions. The locus presenting the highest rate of abnormalities was D1OS221, which maps to 10q23-q24. Another region with frequent alterations was 10q21, at the DIOS109 locus. There was no statistical association between microsatellite abnormalities and Gleason grade or tumor stage in the prostate cancer cases studied. These results suggest that microsatellite alterations on the long arm of chromosome 10 are non-random events occurring in prostate cancer and that they may play a role in the process of tumorigenesis in these neoplasms.

Carcinoma↗
PubMed1996

Genetic susceptibility to head and neck squamous cell carcinoma.

BACKGROUND: In addition to influences of exposure to carcinogenic compounds, the development of cancer may depend on an individual intrinsic cancer susceptibility. Biomarkers for cancer susceptibility can be powerful additions to epidemiologic analyses. PURPOSE: This multicenter, case-control analysis combines previously published data and new data to substantiate the value of mutagen sensitivity as a biomarker of susceptibility to head and neck squamous cell carcinoma and, more importantly, to gain insight into the interaction between susceptibility and exposure to carcinogens. METHODS: Mutagen sensitivity (mean number of chromatid breaks per cell of cultured lymphocytes treated with bleomycin in the late S-G2 phase of the cell cycle) was determined in 313 patients with head and neck cancer and in 334 control subjects at two major U.S. medical institutions and one European institution, yielding a unique study population. The ages of the case and control subjects, as well as their history of use of tobacco and alcohol, were also recorded. The relationships between variables were analyzed by use of Student's t tests, Spearman's rank correlations, and multiple linear regression. For estimation of cancer risk, crude odds rations (ORs) were measured and multiple logistic regression was performed. All P values were based on two-sided tests. RESULTS: There were no differences across institutions in the distribution of mutagen sensitivity (Kruskal-Wallis test) for both case subjects and control subjects. Values for case subjects were consistently and significantly (P<.0001) higher than values for control subjects in the overall analyses. Age and tobacco or alcohol use did not influence the outcome in terms of mutagen-sensitivity values for either the case or the control subjects. A mean number of breaks per cell dichotomized at 1.0 was found to be the best predictor of a hypersensitive phenotype. For nonsensitive, heavy smokers, the OR was 11.5 (95% confidence interval [CI] = 5.0-26.6). This risk increased dramatically in mutagen-hypersensitive, heavy smokers to 44.5 (95% CI = 17.4-114.0). Multiple logistic regression analysis confirmed these results, and a significant trend was found (P<.01) for the dose-dependent increase in cancer risk by smoking. The consumption of alcohol potentiated the effects of smoking, resulting in an OR of 57.5 (95% CI = 17.5-188.0) in hypersensitive persons. CONCLUSIONS: Mutagen sensitivity was found to be a biomarker of cancer susceptibility. This study underscores the importance of utilizing both susceptibility markers and the exposure data for the identification of persons at high risk of developing cancer. IMPLICATIONS: More accurate risk estimation can define susceptible subgroups who might be targeted for intensive behavioral interventions, surveillance through screening, and enrollment in chemoprevention programs.

Adult↗
PubMed1996

Hormone and antihormone withdrawal: implications for the management of androgen-independent prostate cancer.

OBJECTIVES: To analyze reported clinical outcomes for patients in whom an agent that acts via a steroid hormone receptor was "withdrawn." METHODS: Published reports where agent(s) known to act via steroid hormone receptors were discontinued in patients with relapsing prostatic cancer were retrieved from MEDLINE listings. The trials included patients who progressed on steroidal and nonsteroidal antiandrogens, progestational agents, and estrogens. Included were the specifics of all treatments administered prior to discontinuation of the drugs, concomitant therapies, and factors that might predict a favorable response to "withdrawal." RESULTS: Withdrawal responses were observed following the discontinuation of the antiandrogens flutamide and bicalutamide, flutamide plus aminoglutethimide, estrogens, and progestational agents. In most responding cases, responses were seen in patients with long exposure to the drug. No specific factors were predictive for response. CONCLUSIONS: Withdrawal responses to agents that act via steroid hormone receptors represent a generalized phenomenon that can result in palliation for patients with hormonally relapsed prostate cancer. A trial of "withdrawal therapy" is warranted in patients with relapsing disease prior to the initiation of more toxic therapies. Failure to control for this phenomenon in clinical trials may lead to false attribution of response to a study agent. The data provide support for the concept that androgen independence does not necessarily mean that a tumor is resistant to further hormonal manipulations.

Aminoglutethimide↗
PubMed1996

The relationship between smoking exposure and p53 overexpression in colorectal cancer.

Although epidemiological studies of the relationship between cigarette smoking and colorectal cancer risk have been equivocal, a positive association is consistently found for colorectal adenoma development. We performed an epidemiological study to determine whether p53 protein overexpression, in tumours obtained at the time of resection, is associated with cigarette exposure in colorectal cancer. A total of 163 colorectal cancer cases and 326 healthy controls responded to a standardised questionnaire on colorectal cancer risk factors including detailed information on their history of cigarette smoking. All patients' tumours were analysed immunohistochemically for p53 overexpression using an avidin-biotin immunoperoxidase procedure and polyclonal anti-p53 antibody CM1. Comparison of colorectal cases with controls revealed an elevated risk for ex-smokers (OR = 1.34, 95% CI 0.85-2.12) and current smokers (OR = 1.13, 95% CI 0.63-2.02) when compared with non-smokers. No dose-response relationship was found for total pack-years of smoking (trend test: P = 0.19). However, a trend for total pack-years of smoking was found when p53-positive cases were compared with p53-negative cases suggesting aetiological, heterogeneity (trend test: P = 0.06). Estimating the individual relative risk of developing a p53-positive tumour relative to controls showed no associations for smoking status or total pack-years of smoking. However, when p53-negative cases were compared with controls, an elevated risk was found for ex-smokers (OR = 1.84, 95% CI 1.00-3.37) and current years of smoking (trend test: P = 0.03). Colorectal tumours developing through p53-positive dependent pathways were not associated with smoking exposure. A significant increase in risk was observed for the p53-negative independent pathway with smoking. p53 overexpression appears to be associated with smoking exposure in colorectal cancer.

Adult↗
PubMed1996

Cytophotometry in the monitoring of bladder cancer under intravesical chemotherapy.

OBJECTIVE: We evaluated the DNA cytophotometry in 446 bladder washing samples from 64 patients under mitomycin C after superficial bladder cancer during an observation period of up to 5 years. The aim of the study was to identify patients at high risk of recurrence despite chemotherapy-induced atypical, hence noninformative cytology. METHODS: The prognostic value of cytology and ploidy during chemotherapy was compared with regard to recurrence rates and the median time to recurrence. RESULTS: Aneuploidy identified 8 of 10 patients recurring within 12 months out of 17 patients with atypia at first presentation after surgery, whereas no recurrence was seen after atypia and diploid histograms (p = 0.005, mean follow-up period 62 months). Aneuploidy was the most accurate indicator of short-time recurrence (p < 0.001 by multivariate analysis). Follow-up data showed a relative risk of recurrence of 12.7 following histogram shifts towards aneuploidy and of 1.6 for positive shifts in cytology. CONCLUSION: Cytophotometry is superior to cytology in predicting the outcome in patients under chemotherapy for superficial transitional cell cancer of the bladder.

Administration, Intravesical↗
PubMed1996

Overexpression of p53 protein in a high-risk population of patients with superficial bladder cancer before and after bacillus Calmette-Guérin therapy: correlation to clinical outcome.

PURPOSE: We have previously demonstrated that p53 overexpression is predictive of disease progression and survival in Ta, Tis, and T1 tumors. Instillation of Bacillus Calmette-Guérin (BCG) is now accepted to be the most efficient adjuvant therapy for superficial bladder carcinoma. The aim of this study was to determine if p53 status, assessed before and after intravesical BCG therapy, can predict clinical outcome in a high-risk population of patients with superficial bladder carcinoma. MATERIALS AND METHODS: We examined 196 tissue specimens from 98 patients, obtained immediately before and after intravesical BCG therapy. The pretherapy population was composed of 22 Ta, 57 Tis, and 19 T1 tumors. After BCG, 66 specimens were TO and 32 had residual tumors. Nuclear p53 overexpression was analyzed in relation to time to disease progression and disease-specific survival. RESULTS: The median follow-up duration was 44 months. The detection of nuclear p53 overexpression before BCG therapy did not predict response to BCG therapy. Pre-BCG p53 protein overexpression, response to BCG therapy, and pre-BCG stage were all independent markers of disease progression. In patients with residual disease after BCG therapy (nonresponders), multivariate analysis confirmed that posttherapy p53 overexpression was the only independent marker of disease progression. CONCLUSION: In this high-risk population of patients with superficial bladder tumors, patients who have p53 nuclear overexpression in the tumor and stage T1 disease before BCG therapy are at high risk of disease progression. Furthermore, in the group of patients with residual disease after BCG therapy, p53 status is a better predictor of disease progression than post-BCG stage.

Administration, Intravesical↗
PubMed1996

Androgen receptor CAG repeat lengths in prostate cancer: correlation with age of onset.

The androgen receptor (AR) is a structurally conserved member of the nuclear receptor superfamily. The amino-terminal domain is required for transcriptional activation and contains a region of polyglutamine encoded by CAG trinucleotide repeats. In humans, the number of CAG repeats is polymorphic; the average number is 22 in Caucasian males. Expansion of CAG repeats in the AR has clinical implications for human disease. As androgen influences prostate cancer growth, polymorphisms in CAG repeat length may affect the clinical course of patients with prostate cancer. To test for an association between clinical parameters of human prostate cancer and CAG repeat length, we analyzed normal lymphocyte DNA from 109 patients. The CAG region of the AR was amplified by the PCR. Reaction products were then amplified using end-labeled internal primers, cut at the internal PstI site and assayed on sequencing gels using a sequence ladder as a size standard. Sequence analysis of several samples validated this method for measurement of CAG repeat number. The median age of patients was 63 yr (range, 42-83), with 104 Caucasian, 2 African American, 1 Asian, and 2 other racial origin. The median repeat length was 25 for patients with stage A, 22 for patients with stage B, 22 for patients with stage C, and 23 for patients presenting with stage D disease. A significant correlation between CAG repeat length and age at onset was observed, whereas correlations with stage, level of prostate-specific antigen at diagnosis, and time to prostate-specific antigen relapse were not significant. Shorter CAG repeat lengths may be associated with the development of prostate cancer in men at a younger age. These data suggest that CAG repeat length can affect the risk of developing prostate cancer.

Adult↗
PubMed1996

Outcomes of initial surveillance of invasive squamous cell carcinoma of the penis and negative nodes.

PURPOSE: We determined factors predictive of inguinal nodal relapse in patients with stages T1 to 3NOMO squamous cell penile cancer treated initially with surveillance of inguinal nodes. MATERIALS AND METHODS: Between 1980 and 1994, in 42 patients with stages T1 to 3NOMO squamous cell penile cancer of 60 with invasive disease seen at our center the inguinal nodes were surveyed after definitive treatment of the primary tumor. Clinical inguinal nodal recurrences were treated with inguinal lymphadenectomy. RESULTS: A total of 26 patients (62%) had inguinal nodal recurrences during followup, with 50% occurring within 1.4 years and 75% within 2.8 years of resection of the primary tumor. The only factor predicting nodal relapse was grade of the primary tumor at initial treatment. Patients with grade 1 tumors had a 45% long-term actuarial relapse-free survival rate. All other groups had a 100% actuarial nodal relapse rate. Of the patients 10% had metastatic disease without nodal recurrence. CONCLUSIONS: Invasive penile cancer may be associated with inguinal lymph node and hematogenous metastasis. A strong case for prophylactic bilateral inguinal lymphadenectomy can be made in patients with primary tumors other than grade 1, since surveillance of these patients will not spare them eventual lymphadenectomy and may potentially compromise survival by delaying surgery. Patients with grade 1 tumors may be offered either careful surveillance or prophylactic bilateral inguinal lymphadenectomy depending on the clinical circumstances and patient preference.

Adult↗