Revisiting the Landscape of Potential Small and Drug Substance Related Nitrosamines in Pharmaceuticals

N-Nitrosamines are a class of indirect acting mutagens, as their metabolic degradation leads to the formation of the DNA-alkylating diazonium ion. Following up on the in-silico identification of thousands of nitrosamines that can potentially be derived from small molecule drugs and their known impurities described in a previous publication, we have now re-analyzed this dataset to apply EMA's Carcinogenic Potency Categorization Approach (CPCA) introduced with the 16th revision of their Q&A document for Marketing Authorization Holders. We find that the majority of potential nitrosamines from secondary amine precursors belongs to potency categories 4 and 5, corresponding to an acceptable daily intake of 1500 ng, whereas nitrosamines from tertiary amine precursors distribute more evenly among all categories, resulting in a substantial number of structures that are assigned the more challenging acceptable intakes of 18 ng/day and 100 ng/day for potency categories 1 and 2, respectively. However, the nitrosative dealkylation pathway for tertiary amine is generally far slower than the direct nitrosation on secondary amines, with a direct nitrosation mechanism suspected only for structures featuring electron-rich (hetero)aromatic substituents. This allows for greater focus towards those structures that require further review, and we demonstrate that their number is not substantial. In addition, we reflect on the nitrosamine risk posed by secondary amine API impurities and demonstrate that based on the ICH Q3A/B identification threshold unknown impurities may exist that could be transformed to relevant amounts of NA. We also demonstrate that the analytical sensitivity required for the quantification of high potency nitrosamines can be problematic especially for high dose APIs. In summary, the regulatory framework rolled out with the latest Q&A document represents a substantial improvement compared with the previous situation, but further refinement through interaction between manufacturers, regulators, not-for-profit and academic institutions will be required to ensure patient access to vital medicines without compromising safety.

Evaluation of QSAR models for predicting mutagenicity: outcome of the Second Ames/QSAR international challenge project

Quantitative structure-activity relationship (QSAR) models are powerful in silico tools for predicting the mutagenicity of unstable compounds, impurities and metabolites that are difficult to examine using the Ames test. Ideally, Ames/QSAR models for regulatory use should demonstrate high sensitivity, low false-negative rate and wide coverage of chemical space. To promote superior model development, the Division of Genetics and Mutagenesis, National Institute of Health Sciences, Japan (DGM/NIHS), conducted the Second Ames/QSAR International Challenge Project (2020-2022) as a successor to the First Project (2014-2017), with 21 teams from 11 countries participating. The DGM/NIHS provided a curated training dataset of approximately 12,000 chemicals and a trial dataset of approximately 1,600 chemicals, and each participating team predicted the Ames mutagenicity of each trial chemical using various Ames/QSAR models. The DGM/NIHS then provided the Ames test results for trial chemicals to assist in model improvement. Although overall model performance on the Second Project was not superior to that on the First, models from the eight teams participating in both projects achieved higher sensitivity than models from teams participating in only the Second Project. Thus, these evaluations have facilitated the development of QSAR models.

Assessing the utility of common arguments used in expert review of in silico predictions as part of ICH M7 assessments

Expert review of two predictions, made by complementary (quantitative) structure-activity relationship models, to an overall conclusion is a key component of using in silico tools to assess the mutagenic potential of impurities as part of the ICH M7 guideline. In lieu of a specified protocol, numerous publications have presented best practise guides, often indicating the occurrence of common prediction scenarios and the evidence required to resolve them. A semi-automated expert review tool has been implemented in Lhasa Limited's Nexus platform following collation of these common arguments and assignment to the associated prediction scenarios made by Derek Nexus and Sarah Nexus. Using datasets primarily donated by pharmaceutical companies, an automated analysis of the frequency these prediction scenarios occur, and the likelihood of the associated arguments assigning the correct resolution, could then be conducted. This article highlights that a relatively small number of common arguments may be used to accurately resolve many prediction scenarios to a single conclusion. The use of a standardised method of argumentation and assessment of evidence for a given impurity is proposed to improve the efficiency and consistency of expert review as part of an ICH M7 submission.

Updating the Dermal Sensitisation Thresholds using an expanded dataset and an in silico expert system

The Dermal Sensitisation Thresholds (DST) are Thresholds of Toxicological Concern, which can be used to justify exposure-based waiving when conducting a skin sensitisation risk assessment. This study aimed to update the published DST values by expanding the size of the Local Lymph Node Assay dataset upon which they are based, whilst assigning chemical reactivity using an in silico expert system (Derek Nexus). The potency values within the expanded dataset fitted a similar gamma distribution to that observed for the original dataset. Derek Nexus was used to classify the sensitisation activity of the 1152 chemicals in the expanded dataset and to predict which chemicals belonged to a High Potency Category (HPC). This two-step classification led to three updated thresholds: a non-reactive DST of 710 μg/cm² (based on 79 sensitisers), a reactive (non-HPC) DST of 73 μg/cm² (based on 331 sensitisers) and an HPC DST of 1.0 μg/cm² (based on 146 sensitisers). Despite the dataset containing twice as many sensitisers, these values are similar to the previously published thresholds, highlighting their robustness and increasing confidence in their use. By classifying reactivity in silico the updated DSTs can be applied within a skin sensitisation risk assessment in a reproducible, scalable and accessible manner.

Development of a network of carcinogenicity adverse outcome pathways and its employment as an evidence framework for safety assessment

The traditional paradigm for safety assessment of chemicals for their carcinogenic potential to humans relies heavily on a battery of well-established genotoxicity tests, usually followed up by long-term, high-dose rodent studies. There are a variety of problems with this approach, not least that the rodent may not always be the best model to predict toxicity in humans. Consequently, new approach methodologies (NAMs) are being developed to replace or enhance predictions coming from the existing assays. However, a combination of the data arising from NAMs is likely to be required to improve upon the current paradigm, and consequently a framework is needed to combine evidence in a meaningful way. Adverse outcome pathways (AOPs) represent an ideal construct on which to organize this evidence. In this work, a data structure outlined previously was used to capture AOPs and evidence relating to carcinogenicity. Knowledge held within the predictive system Derek Nexus was extracted, built upon, and arranged into a coherent network containing 37 AOPs. 60 assays and 351 in silico alerts were then associated with KEs in this network, and it was brought to life by associating data and contextualizing evidence and predictions for over 13,400 compounds. Initial investigations into using the network to view knowledge and reason between evidence in different ways were made. Organizing knowledge and evidence in this way provides a flexible framework on which to carry out more consistent and meaningful carcinogenicity safety assessments in many different contexts.

Use of Lhasa Limited Products for the In Silico Prediction of Drug Toxicity

Lhasa Limited have had a role in the in silico prediction of drug and other chemical toxicity for over 30 years. This role has always been multifaceted, both as a provider of predictive software such as Derek Nexus, and as an honest broker for the sharing of proprietary chemical and toxicity data. A changing regulatory environment and the drive for the Replacement, Reduction and Refinement (the 3Rs) of animal testing have led both to increased acceptance of in silico predictions and a desire for the sharing of data to reduce duplicate testing. The combination of these factors has led to Lhasa Limited providing a suite of products and coordinating numerous data-sharing consortia that do indeed facilitate a significant reduction in the testing burden that companies would otherwise be laboring under. Many of these products and consortia can be organized into workflows for specific regulatory use cases, and it is these that will be used to frame the narrative in this chapter.

The importance of expert review to clarify ambiguous situations for (Q)SAR predictions under ICH M7

The use of in silico predictions for the assessment of bacterial mutagenicity under the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) M7 guideline is recommended when two complementary (quantitative) structure-activity relationship (Q)SAR models are used. Using two systems may increase the sensitivity and accuracy of predictions but also increases the need to review predictions, particularly in situations where results disagree. During the 4th ICH M7/QSAR Workshop held during the Joint Meeting of the 6th Asian Congress on Environmental Mutagens (ACEM) and the 48th Annual Meeting of the Japanese Environmental Mutagen Society (JEMS) 2019, speakers demonstrated their approaches to expert review using 20 compounds provided ahead of the workshop that were expected to yield ambiguous (Q)SAR results. Dr. Chris Barber presented a selection of the reviews carried out using Derek Nexus and Sarah Nexus provided by Lhasa Limited. On review of these compounds, common situations were recognised and are discussed in this paper along with standardised arguments that may be used for such scenarios in future.

Multidisciplinary clinic approach improves overall survival outcomes of patients with metastatic germ-cell tumors

Background

To report our experience utilizing a multidisciplinary clinic (MDC) at Indiana University (IU) since the publication of the International Germ Cell Cancer Collaborative Group (IGCCCG), and to compare our overall survival (OS) to that of the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) Program.

Patients and methods

We conducted a retrospective analysis of all patients with metastatic germ-cell tumor (GCT) seen at IU from 1998 to 2014. A total of 1611 consecutive patients were identified, of whom 704 patients received an initial evaluation by our MDC (including medical oncology, pathology, urology and thoracic surgery) and started first-line chemotherapy at IU. These 704 patients were eligible for analysis. All patients in this cohort were treated with cisplatin-etoposide-based combination chemotherapy. We compared the progression-free survival (PFS) and OS of patients treated at IU with that of the published IGCCCG cohort. OS of the IU testis cancer primary cohort (n = 622) was further compared with the SEER data of 1283 patients labeled with 'distant' disease. The Kaplan-Meier method was used to estimate PFS and OS.

Results

With a median follow-up of 4.4 years, patients with good, intermediate, and poor risk disease by IGCCCG criteria treated at IU had 5-year PFS of 90%, 84%, and 54% and 5-year OS of 97%, 92%, and 73%, respectively. The 5-year PFS for all patients in the IU cohort was 79% [95% confidence interval (CI) 76% to 82%]. The 5-year OS for the IU cohort was 90% (95% CI 87% to 92%). IU testis cohort had 5-year OS 94% (95% CI 91% to 96%) versus 75% (95% CI 73% to 78%) for the SEER 'distant' cohort between 2000 and 2014, P-value <0.0001.

Conclusion

The MDC approach to GCT at high-volume cancer center associated with improved OS outcomes in this contemporary dataset. OS is significantly higher in the IU cohort compared with the IGCCCG and SEER 'distant' cohort.

Commentary on "Prognostic effect of carcinoma in situ in muscle-invasive urothelial carcinoma patients receiving neoadjuvant chemotherapy."

BACKGROUND

Carcinoma in situ (CIS) is a poor prognostic finding in urothelial carcinoma. However, its significance in muscle-invasive urothelial carcinoma (MIUC) treated with neoadjuvant chemotherapy (NAC) is uncertain. We assessed the effect of CIS found in pretreatment transurethral resection of bladder tumor (TURBT) biopsies on the pathologic and clinical outcomes.

MATERIALS AND METHODS

Subjects with MIUC treated with NAC before cystectomy were identified. The pathologic complete response (pCR) rates stratified by TURBT CIS status were compared. The secondary analyses included tumor response, progression-free survival (PFS), overall survival (OS), and an exploratory post hoc analysis of patients with pathologic CIS only (pTisN0) at cystectomy.

RESULTS

A total of 137 patients with MIUC were identified. TURBT CIS was noted in 30.7% of the patients. The absence of TURBT CIS was associated with a significantly increased pCR rate (23.2% vs. 9.5%; odds ratio = 4.08; 95% CI: 1.19-13.98; P = 0.025). Stage pTisN0 disease was observed in 19.0% of the TURBT CIS patients. TURBT CIS status did not significantly affect the PFS or OS outcomes. Post hoc analysis of the pTisN0 patients revealed prolonged median PFS (104.5 vs. 139.9 months; P = 0.055) and OS (104.5 vs. 152.3 months; P = 0.091) outcomes similar to those for the pCR patients.

CONCLUSION

The absence of CIS on pretreatment TURBT in patients with MIUC undergoing NAC was associated with increased pCR rates, with no observed differences in PFS or OS. Isolated CIS at cystectomy was frequently observed, with lengthy PFS and OS durations similar to those for pCR patients. Further studies aimed at understanding the biology and clinical effect of CIS in MIUC are warranted.

Molecular genetic evidence supporting the neoplastic nature of stromal cells in 'fibrosis' after chemotherapy for testicular germ cell tumours

A residual retroperitoneal mass containing only fibrosis and necrosis is present in 40-52% of patients with advanced testicular germ cell tumours after chemotherapy. The biological nature and genetic characteristics of the stromal cells in these residual masses have not been adequately investigated. Laser-microdissected stromal cells from 27 patients who underwent retroperitoneal lymph node dissection after chemotherapy for metastatic testicular germ cell tumour were analysed. Allelic loss in the stromal cells of fibrosis was present at one or more of the ten microsatellite DNA loci examined in 23 (85%) of the cases. Chromosome arm 12p anomalies, the hallmark of germ cell neoplasia, were present in nine (33%) cases. The high frequency of allelic losses and chromosome arm 12p anomalies in the stromal cells from residual retroperitoneal fibrous masses after chemotherapy for testicular germ cell tumours suggests that the stromal cells are derived from the same tumour progenitor cells as the pre-existing metastatic germ cell tumour.

Biochemical disease-free survival in patients with a high prostate-specific antigen level (20-100 ng/mL) and clinically localized prostate cancer after radical prostatectomy

OBJECTIVE

To examine our experience with radical prostatectomy (RP) in patients with a serum prostate-specific antigen (PSA) level of > 20 ng/mL (who are sometimes considered poor candidates for RP) to determine the outcome and possible predictors of a favourable outcome.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of 79 patients who underwent RP with an initial PSA of 20-100 ng/mL. Biochemical disease-free survival (BDFS) was assessed using the Kaplan-Meier method and predictors of treatment outcome examined by uni- and multivariate analysis. Patients excluded from the analysis were 11 (14%) whose surgery was aborted after finding cancerous pelvic nodes and who did not undergo RP; four others with normal nodes during RP who had metastatic tumour on permanent sections; and 14 who had follow-up data for < 2 years.

RESULTS

The mean (sd) age of the 50 patients in the final study population was 63 (7) years and the mean PSA 37.9 (16.0) ng/mL. The median (range) follow-up was 54 (24-120) months. The BDFS was 60% at 3 years and 48% at 5 years of follow-up. Two patients developed a local recurrence and eight developed metastatic disease. On logistic regression analysis of factors influencing BDFS, only extracapsular extension of disease was predictive of PSA recurrence; no preoperative factor was significant. When time to PSA recurrence was assessed by Cox regression analysis, again only extracapsular extension was predictive, with no preoperative variable a statistically significant predictor.

CONCLUSIONS

Patients with a high serum PSA level (20-100 ng/mL) may be appropriate candidates for RP. While the cancer-free survival is not as good as in patients with a lower PSA, a significant percentage of patients achieve BDFS. No preoperative variables were predictive of disease-free survival or time to PSA recurrence.

Accuracy of predicting long-term prostate specific antigen outcome based on early prostate specific antigen recurrence results after radical prostatectomy

PURPOSE

We determined how prostate specific antigen (PSA) doubling time changed with time and whether an early measure of doubling time would accurately predict long-term PSA values and clinical outcome in a cohort of patients followed expectantly after radical prostatectomy.

MATERIALS AND METHODS

We analyzed data on 121 patients with PSA recurrence after radical retropubic prostatectomy. Group and individual analyses were performed on 60 patients who met study inclusion criteria. PSA doubling time was calculated and a curve was plotted using logarithmic transformation with linear regression and least squares analysis. In analysis 1 patients were placed into 3 subgroups according to doubling time. Doubling time was calculated per subgroup and the slopes of the aggregate curves were compared to determine how doubling time changed with time. In analysis 2 we calculated early doubling time per patient using only the initial 2 detectable PSA values and compared it with eventual doubling time in each using all PSA values. In addition, we analyzed how doubling time correlated with the clinical course.

RESULTS

Using the group methodology there was no statistically significant acceleration or deceleration with time in doubling time slope in any of the 3 subgroups. On individual analysis we noted a weak correlation of early with eventual doubling time (correlation coefficient 0.69, p = 0.01). In 88% of patients eventual doubling time was not within 10% of early doubling time. Metastasis developed in 60% of patients with an eventual DT of 0 to 6 months, while 80% with an eventual doubling time of 6 to 12 months had no evidence of local or metastatic disease. No patients with an eventual doubling time of greater than 12 months have had metastatic disease and only 4 (16%) had local recurrence, which was treated with radiation therapy. In 8 of the 14 patients (23%) with local recurrence or metastatic disease early doubling time predicted eventual doubling time. Early doubling time was more rapid and slower than eventual doubling time in 5 and 1, respectively, of the remaining cases, which would have placed them in a different subgroup.

CONCLUSIONS

On group analysis PSA doubling time appeared to be constant with time and there was no evidence that it accelerated with time in our dataset of PSA recurrence after radical prostatectomy. On individual analysis early doubling time showed a weak but statistically significant correlation with eventual doubling time. However, there was significant inaccuracy when predicting PSA doubling time based on early PSA values in individuals. Generally early projections of doubling time tend to over predict tumor biological aggressiveness, that is local recurrence or metastasis. A need remains for more accurate predictors of the rate of disease progression at initial PSA recurrence to determine accurately early in the clinical course the patients who may benefit from additional therapy. Currently no patient in our study has died of prostate cancer.

Early-stage testis cancer

The treatment of low-stage testis cancer (defined as clinical stage I or low-volume clinical stage II disease) varies, depending on whether or not the orchiectomy specimen reveals seminoma or nonseminoma. Treatments for clinical stage I seminoma include radiotherapy to the retroperitoneum, surveillance, or two courses of carboplatin chemotherapy. Until the results of an ongoing randomized study comparing radiotherapy with two courses of carboplatin are known, standard accepted treatments currently include radiotherapy or surveillance. In nonbulky clinical stage II seminoma, therapeutic options include radiotherapy or cisplatin-based chemotherapy. For clinical stage I nonseminoma, equivalent short-term survival rates are obtained with either nerve-sparing retroperitoneal lymph node dissection (RPLND), surveillance, or two courses of BEP (bleomycin, etoposide, and platinum) chemotherapy. However, minimization of toxicity of treatment would argue that the two preferred treatments in clinical stage I nonseminoma are nerve-sparing RPLND or surveillance. For low- volume clinical stage II nonseminoma, options include three courses of BEP or primary RPLND. The overall chance for cure is essentially the same for either of these options. Therefore, in each clinical stage of early-stage testis cancer, therapeutic options exist that, based upon current data, are therapeutically equivalent in the short term. Therefore, the ultimate choice of therapy is also dependent upon the short- and long-term toxicity of therapy and the likelihood of late recurrence of disease.

Germ cell tumor associated primitive neuroectodermal tumors

PURPOSE

This retrospective review was done to assess the prognosis and response in patients presenting with primitive neuroectodermal tumor admixed with germ cell tumor.

MATERIALS AND METHODS

Of the 40 patients treated at our institution from 1984 to 1999, 15 had initial stage I and 25 had initial metastatic disease. Median followup after the diagnosis was 25 months (range 4 to 142).

RESULTS

Of the 40 patients 15 presented with clinical stage I disease, including 9 treated with retroperitoneal lymph node dissection and 6 who elected surveillance. Seven of the 9 patients had normal lymph nodes and all continuously had no evidence of disease. Two of the 9 patients had lymph nodes involved with teratoma with or without primitive neuroectodermal tumor. Retroperitoneal relapse in 5 of the 6 patients on surveillance was treated with cisplatin based chemotherapy followed by post-chemotherapy retroperitoneal lymph node dissection. Residual primitive neuroectodermal tumor was noted in 4 of the 5 patients and only 3 of 6 are currently without disease at a median followup of 17 months (range 15 to 69). A total of 25 patients presented with metastatic disease, of whom 23 underwent cisplatin based chemotherapy. Only 3 patients achieved complete remission with chemotherapy alone and 2 of the 3 subsequently relapsed. Of the remaining 20 patients 16 underwent post-chemotherapy retroperitoneal lymph node dissection, including 11 with primitive neuroectodermal tumor in the resected specimen. Two of these 11 patients have continuously had no evidence of disease, while an additional 3 currently have no evidence of disease after further therapy. Teratoma was present in the resected specimen in 5 of 16 patients, of whom 2 have continuously had no evidence of disease, while an additional 2 currently have no evidence of disease after further surgical resection. Therefore, 11 of 25 patients who presented with metastatic disease currently have no evidence of disease at a median followup of 19 months (range 2 to 111).

CONCLUSIONS

Primitive neuroectodermal tumor in the orchiectomy specimen has adverse prognostic significance. This condition in the retroperitoneum is potentially curable by retroperitoneal lymph node dissection but rarely eradicated by chemotherapy. Therefore, we recommend retroperitoneal lymph node dissection for all clinical stage I cases with primitive neuroectodermal tumor in the orchiectomy specimen. Patients who present with metastatic primitive neuroectodermal tumor should be treated aggressively with surgical resection as an integral part of the therapeutic strategy.

Aortic replacement during post-chemotherapy retroperitoneal lymph node dissection

PURPOSE

We reviewed the records of 15 patients with metastatic germ cell cancer who underwent aortic resection and replacement during post-chemotherapy retroperitoneal lymph node dissection to determine the morbidity and the therapeutic benefit.

MATERIALS AND METHODS

Between 1970 and 1998, 1,250 patients underwent post-chemotherapy retroperitoneal lymph node dissection. Our retrospective review revealed that 15 patients underwent aortic replacement at that operation.

RESULTS

In addition to aortic replacement 11 patients underwent 15 additional procedures, including nephrectomy in 7, vena caval resection in 3, pulmonary resection in 1, small bowel resection in 2, 1 hepatic resection in 1 and L4 vertebrectomy in 1. No patient had necrosis as the only pathological condition. Three patients (20%) had teratoma and 12 (80%) had viable tumor in the retroperitoneal specimen. All 4 patients who underwent post-chemotherapy retroperitoneal lymph node dissection and aortic replacement after induction chemotherapy alone have no evidence of disease. Only 1 of the 11 patients who received salvage chemotherapy with or without previous post-chemotherapy retroperitoneal lymph node dissection have no evidence of disease. Overall 33% of the patients have no evidence of disease. There were no graft related complications.

CONCLUSIONS

Aortic resection at post-chemotherapy retroperitoneal lymph node dissection is justified based on therapeutic benefit and morbidity.

Vertical rectus muscle augmented transposition in Duane syndrome

INTRODUCTION

Reduction or elimination of face turn and esotropia in the primary position while maintaining the largest possible diplopia-free field are the major surgical goals in Duane syndrome with esotropia. Unsatisfactory postoperative results may occur because of limitation in adduction, poor abduction, or induced vertical deviations. Recent reports have shown enhanced results from rectus muscle transposition techniques when a lateral posterior augmentation fixation is placed.

METHODS

Preoperative and postoperative data of 2 groups of subjects who had Duane syndrome with esotropia in primary position and markedly reduced abduction were comparatively analyzed. Group A consisted of subjects who had transposition of both vertical rectus muscles to the lateral rectus muscle with a posterior lateral augmentation suture placed in each transposed muscle. Group B subjects had transposition of both vertical rectus muscles to the lateral rectus muscle without the posterior lateral augmentation suture.

RESULTS

A total of 32 subjects in group A and 22 subjects in group B were analyzed. In group A, anomalous head position improved 19.1 degrees +/- 10.3 degrees compared with group B subjects who improved 10.6 degrees +/- 5.8 degrees (P <.05). In group A, esotropia in primary position improved 16.4 +/- 9.2 PD compared with group B subjects who improved 8.5 +/- 6.9 PD (P <.05).

CONCLUSIONS

Subjects with Duane syndrome and esotropia in primary position who had undergone augmented transposition of the vertical rectus muscles obtained improved head position and better alignment in primary position and had a reduction in the incidence of reoperation for undercorrection when compared with similar patients who had undergone vertical rectus muscle transposition without posterior lateral augmentation sutures.

Altered expression of Ape1/ref-1 in germ cell tumors and overexpression in NT2 cells confers resistance to bleomycin and radiation

The human AP endonuclease (Ape1 or ref-1) DNA base excision repair (BER) enzyme is a multifunctional protein that has an impact on a wide variety of important cellular functions including oxidative signaling, transcription factor regulation, and cell cycle control. It acts on mutagenic AP (baseless) sites in DNA as a critical member of the DNA BER repair pathway. Moreover, Ape1/ref-1 stimulates the DNA-binding activity of transcription factors (Fos-Jun, nuclear factor-kappaB, Myb, ATF/cyclic AMP-responsive element binding protein family, HIF-1alpha, HLF, PAX, and p53) through a redox mechanism and thus represents a novel component of signal transduction processes that regulate eukaryotic gene expression. Ape1/ref-1 has also been shown to be closely linked to apoptosis associated with thioredoxin, and altered levels of Ape1/ref-1 have been found in some cancers. In a pilot study, we have examined Ape1/ref-1 expression by immunohistochemistry in sections of germ cell tumors (GCTs) from 10 patients with testicular cancer of various histologies including seminomas, yolk sac tumors, and malignant teratomas. Ape1/ref-1 was expressed at relatively high levels in the tumor cells of nearly all sections. We hypothesized that elevated expression of Ape1/ref-1 is responsible in part for the resistance to therapeutic agents. To answer this hypothesis, we overexpressed the Ape1/ref-1 cDNA in the GCT cell line NT2/D1 using retroviral gene transduction with the vector LAPESN. Using an oligonucleotide cleavage assay and immunohistochemistry to assess Ape1/ref-1 repair activity and expression, respectively, we found that the repair activity and relative Ape1/ref-1 expression in GCT cell lines are directly related. NT2/D1 cells transduced with Ape1/ref-1 exhibited 2-fold higher AP endonuclease activity in the oligonucleotide cleavage assay, and this was reflected in a 2-3-fold increase in protection against bleomycin. Lesser protection was observed with gamma-irradiation. We conclude that: (a) Ape1/ref-1 is expressed at relatively high levels in some GCTs; (b) elevated expression of Ape1/ref-1 in testicular cancer cell lines results in resistance to certain therapeutic agents; and (c) Ape1/ref-1 expression in GCT cell lines determined by immunohistochemistry and repair activity assays parallels the level of protection from bleomycin. We further hypothesize that elevated Ape1/ref-1 levels observed in human testicular cancer may be related to their relative resistance to therapy and may serve as a diagnostic marker for refractory disease. To our knowledge, this is the first example of overexpressing Ape1/ref-1 in a mammalian system resulting in enhanced protection to DNA-damaging agents.

Validation of a prediction model and its predictors for the histology of residual masses in nonseminomatous testicular cancer

PURPOSE

We validated a prediction model for histology of residual retroperitoneal masses, either benign or tumor, in patients treated with chemotherapy for metastatic nonseminomatous testicular cancer.

MATERIALS AND METHODS

We studied 276 patients treated with chemotherapy before retroperitoneal lymph node dissection at Indiana University Medical Center between 1985 and 1999. A previously developed prediction model was modified to provide predictions for the Indiana population based on 5 predictors. For these predictors, including teratomatous elements in the primary tumor, pre-chemotherapy tumor markers (alpha-fetoprotein and human chorionic gonadotropin), size of the residual mass and reduction in mass size, univariate and multivariate odds ratios were determined. The modified model was evaluated by calculating the concordance statistic and studying model reliability.

RESULTS

All odds ratios from univariate and multivariate analyses were in the expected directions. The modified model had good discriminative ability (concordance statistic 0.79). However, the predicted probabilities for benign tissue were generally too high due to the low prevalence of benign tissue (76 of 276 cases or 28%).

CONCLUSIONS

This study confirms the predictive ability of formerly identified predictors for the histology of residual retroperitoneal masses in testicular cancer. However, the previously developed prognostic model must be adjusted for the local overall ratio of benign versus tumor histology to provide reliable predictions in the Indiana population.

Breast cancer and pregnancy

A diagnosis of breast cancer during pregnancy or the postpartum period is an unfortunate occurrence. Hormonal factors appear to play an important role early on in the development of breast cancer; however, pregnancy itself does not clearly influence the outcome of an established breast cancer. Diagnosis can be challenging in a pregnant woman and delays in diagnosis are common. Treatment decisions must take into consideration not only toxicity to the mother, but short- and long-term consequences for the fetus as well. Other special considerations with pregnancy-associated breast cancer include the timing of delivery, the potential for nursing, and concerns for future fertility. In general, management of pregnancy associated breast cancer follows the same principals as in non-pregnant patients of similar age. With thoughtful application of available therapies, outcome can be optimized for both the mother and her child.

Clinical stage I pure yolk sac tumor of the testis in adults has different clinical behavior than juvenile yolk sac tumor

PURPOSE

We evaluated the clinical behavior of clinical stage I pure yolk sac tumor of the testis in adults to determine whether the behavior of this entity is different than that of clinical stage 1 nonseminoma.

MATERIALS AND METHODS

We searched the testis cancer database at our institution for adults with clinical stage I pure yolk sac tumor of the testis who underwent retroperitoneal lymph node dissection. We identified 12 such patients and reviewed the database and hospital charts to determine clinical behavior.

RESULTS

Disease was pathological stage I in 8 of the 12 patients (66%), including 1 with recurrence after retroperitoneal lymph node dissection. Disease was pathological stage II in 14 patients (33%), including 1 who remains disease-free after electing adjuvant bleomycin, etoposide and cisplatin. Of the 3 patients who elected observation after retroperitoneal lymph node dissection only 1 has had recurrence, while 2 (66%) were cured by retroperitoneal lymph node dissection only.

CONCLUSIONS

Contrary to juvenile yolk sac tumor, which has a strong tendency toward hematogenous metastasis, the behavior of clinical stage I adult pure yolk sac tumor is similar to that of all other stage I nonseminomas in adulthood.

Characterization and predictors of prostate specific antigen progression rates after radical retropubic prostatectomy

PURPOSE

Detectable serum prostate specific antigen (PSA) after radical prostatectomy indicates recurrent disease and treatment failure. We characterized PSA recurrence after prostatectomy and identified predictors of rapid PSA progression.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 165 patients with detectable PSA after radical prostatectomy to characterize the rate of PSA increase and correlate this rate with the possible predictors of rapid PSA progression known at prostatectomy.

RESULTS

For a median of 48 months postoperatively we followed 142 patients with PSA recurrence after radical prostatectomy who received no immediate adjuvant therapy. PSA doubling time was less than 6, greater than 6, 12, 18 and 24 months in 46%, 54%, 18%, 11% and 9% of cases, while time to PSA 50 ng./ml. was greater than 5, 10, 15 and 20 years in 69%, 34%, 22% and 9%, respectively. Univariate and multivariate analyses revealed that rapid PSA doubling time was associated with Gleason secondary grade, Gleason score and time to initial detectable PSA (p = 0.019, 0.031 and 0.0001, and p = 0.043, 0.045 and 0.0001, respectively).

CONCLUSIONS

PSA recurrence progresses at a greatly variable rate and many recurrences progress slowly with a long doubling time. Gleason secondary grade and score appear to be predictive of rapid PSA progression. No other pathological features were predictive of rapid PSA progression.

Retroperitoneal lymph node dissection for the management of clinical stage I nonseminoma

PURPOSE

We review the rationale for the use of retroperitoneal lymph node dissection for clinical stage I nonseminomatous testis cancer.

MATERIALS AND METHODS

The published literature regarding the alternative treatments for clinical stage I nonseminoma was reviewed as well as the personal experience of the authors to define the role of retroperitoneal lymph node dissection.

RESULTS

Retroperitoneal lymph node dissection alone is curative in 50% to 75% of patients with pathological stage II disease. The only significant long-term morbidity is a 1% chance of small bowel obstruction. If recurrence develops after retroperitoneal lymph node dissection, it is virtually always curable with cisplatin based chemotherapy.

CONCLUSIONS

Retroperitoneal lymph node dissection retains a therapeutic and staging capability in these patients. The probability for cure, short and long-term morbidity, and minimal need for long-term followup in these patients indicates that retroperitoneal lymph node dissection continues to be standard therapy for clinical stage I nonseminoma.

Risk of systemic metastases in clinical stage I nonseminoma germ cell testis tumor managed by retroperitoneal lymph node dissection

PURPOSE

We assess the risk of systemic recurrence after retroperitoneal lymph node dissection for clinical stage I nonseminoma germ cell testis tumor based on predominance of embryonal carcinoma and/or vascular invasion in the orchiectomy specimen.

MATERIALS AND METHODS

A total of 292 cases of clinical stage I nonseminoma germ cell testis tumor treated with retroperitoneal lymph node dissection from 1990 to 1995 were identified from the Indiana University database. A minimum of 2 years of followup was required for study entry. Review of the written pathological reports classified tumors as embryonal carcinoma predominant, when it was present at a level greater than any other histology, nonpredominant, when it was present but not as the main histological subtype, and absent. Vascular invasion was categorized as present or absent.

RESULTS

Of the 292 cases 226 (77. 4%) were pathological stage I and relapse rate after retroperitoneal lymph node dissection was 10.2%. Vascular invasion and embryonal carcinoma predominance in the orchiectomy specimen were predictors of relapse in this group. None of the 35 pathological stage II cases treated with adjuvant chemotherapy had relapse, whereas relapse occurred in 7 of 31 pathological stage II cases (22.6%) not treated with adjuvant chemotherapy.

CONCLUSIONS

Pathological stage I cases with predominant embryonal carcinoma and/or vascular invasion in the orchiectomy specimen have a higher probability of systemic recurrence after retroperitoneal lymph node dissection. Dissection alone still has a major therapeutic impact (77%) in patients with clinical stage I, pathological stage II nonseminoma germ cell testis tumor.

Tumors of the small intestine

This collective review includes all available case reports and series of smooth muscle (stromal) tumors of the small intestine in the world literature from 1881 to 1996. We identified 1074 patients with leiomyoma (LM) and 1689 with leiomyosarcoma (LMS). Our purpose was to update our previous review, which encompassed case reports and series from 1881 to 1959, which included 350 LMs and 257 LMSs. The peak incidence of smooth muscle tumors in the small intestine in both male and female patients was between the ages of 50 and 59. Most commonly, the presenting complaint was gastrointestinal bleeding. Computed tomography was found to detect LM and LMS most successfully and had the additional advantage of locating metastatic disease. The jejunum contained the highest numbers of smooth muscle tumors, followed by the ileum and then the duodenum, with malignant lesions in all locations typically attaining larger diameters than benign tumors. The overall rate of metastatic spread of LMS ranged from 24% to 50%, with the liver being most commonly involved. Unlike other sarcomas, both hematogenous and lymphatic spread were common. The 5-year survival of 705 patients with LMS from 22 series was 27. 8%. For both benign and malignant smooth muscle tumors of the small intestine, surgery remains the treatment of choice, with little efficacy reported for irradiation, chemotherapy, or both.

Tumors of the appendix and colon

This collective review includes all available case reports of smooth muscle (stromal) tumors of the appendix and large intestine in the world literature. When compiling this review, we endeavored to examine cumulative as well as recently collected data on both benign and malignant smooth muscle tumors spanning the period 1875 to 1996. In total, there were reports of 331 leiomyomas (LMs) and 263 leiomyosarcomas (LMSs). The peak age of incidence of LM was 30 to 39 years, and the peak age of incidence of LMSs was 50 to 59 years. The female/male ratio was slightly higher for LM, and the male/female ratio was higher for LMS. The descending colon and sigmoid colon were the most common sites of both benign and malignant smooth muscle tumors. The growth of LMs most often occurred extraluminally, whereas LMSs tended to grow within the lumen of the colon. With both tumor types pain was the most frequent presenting complaint, followed less commonly by complaints of a palpable mass or gastrointestinal bleeding. LMSs tended to be larger at diagnosis than LMs, though the duration of symptoms for both types of tumor was most often reported to be between 1 month and 1 year. Finally, LMSs were found to metastasize mo

Tumors of the rectum and anal canal

This collective review includes all available case reports of smooth muscle (stromal) tumors of the rectum and anal canal in the world literature. When compiling this review we endeavored to present cumulative and recently collected data of both benign and malignant smooth muscle tumors found in the literature spanning the period from 1881 to 1996, which totaled 432 leiomyomas (LMs) and 480 leiomyosarcomas (LMSs) of the anus and rectum. The peak age of frequency for LMs was 40 to 59 years and 50 to 69 years for LMSs; men were slightly more likely to develop both benign and malignant anorectal smooth muscle tumors than women. Intraluminal growth of both LMs and LMSs was more frequently seen than extraluminal or intramural patterns, and tumors were more likely to be found in the rectum than in the anus. Patients with LMs presented most commonly with gastrointestinal (GI) bleeding, a palpable mass, or anorectal pain. As with smooth muscle tumors in other areas of the alimentary tract, symptoms likely persisted for less than 1 year prior to diagnosis. As was also the case for these neoplasms in other GI locations, LMSs tended to be larger than LMs. Approximately 20% of LMSs reported from 1881 to 1996 had metastasized at diagnoses. The local recurrence rate for resectable tumors was more than 80%, exceeding the propensity of LMSs in other areas of the GI tract to recur.

Tumors of the esophagus

This collective review includes all available case reports of smooth muscle (stromal) tumors of the esophagus in the world literature. Compiling this review, we endeavored to examine cumulative and recently collected data of both benign and malignant esophageal smooth muscle tumors found in the literature spanning the period from 1875 to 1996, which totaled 1679 leiomyomas (LMs) and 165 leiomyosarcomas (LMSs). The peak age of occurrence of benign smooth muscle tumors in the esophagus was found to be between the ages of 30 and 59, whereas the highest frequency of malignant tumors was seen later in life, during the decade from age 60 to 69. The most common location of both LMs and LMSs was the lower third of the esophagus. Their patterns of growth differed; LMs were more likely to grow intramurally, and LMSs were predominantly intraluminal. Most patients with LMs presented with dysphagia and pain or discomfort; patients with LMSs additionally commonly complained of weight loss. As with smooth muscle tumors of other areas of the gastrointestinal tract, the duration of symptoms averaged 1 month to 1 year, and malignant tumors grew to larger sizes than benign neoplasms. Approximately one-third of LMSs had metastasized at diagnosis, and there was a 5-year survival rate of approximately 20%.

Tumors of the stomach

This collective review includes all available case reports of smooth muscle (stromal) tumors of the stomach in the world literature from 1762 to 1996. It updates our previous review from 1767 to 1959. Overall, we identified 2189 patients with leiomyoma (LM) and 1594 with leiomyosarcoma (LMS). The peak age of incidence of LM was 50 to 59 years, while LMS was most frequently seen between ages 60 and 69. Women were more likely to develop LM, and men more commonly presented with malignant smooth muscle tumors of the stomach. Concerning the patterns of growth, LMs were more likely to grow intraluminally (endogastric), whereas LMSs were predominantly exogastric. The most common site of LMs was on the anterior or posterior wall of the body of the stomach; LMSs were most likely found along the greater curve. The presenting symptoms of both types of smooth muscle tumors were similar; in decreasing order of frequency they were bleeding, pain, palpable mass, and weight loss. Interestingly, there was no correlation between the size of the tumor and signs or symptoms of bleeding, pain, weight loss, or ulceration, although patients with LMSs were more likely to report weight loss than patients with benign tumors. For LMS, there seemed to be no correlation between tumor size or location and rate of metastasis, although the tumors that grew in a dumbbell shape (i.e., both intraluminally and extraluminally) had a higher frequency of metastasis than other growth patterns. Overall, the rate of metastasis at diagnosis was 35.4%, with the liver, spleen, and regional lymph nodes the most common sites.

Tumors of the oral cavity and pharynx

We have compiled all the reported cases of smooth muscle (stromal) tumors of the oral cavity and pharynx from 1884 through 1996. Our collective data included 139 leiomyomas (LM) and 68 leiomyosarcomas (LMS); but because we did not have sufficient information for 13 cases of LM, we report on only 126; and we report on only 66 of 68 cases of LMS. The peak age of incidence was 40 to 49 years for benign tumors and 50 to 59 years for malignant lesions, with the incidence in men slightly predominating over that in women. The most common sites of LM of the oral cavity and pharynx were the lips, tongue, and hard and soft palate. The most common sites of LMS included the maxilla and mandible. More than 40% of LMs presented as an intraoral mass, and more than half were known to be present for longer than 1 year. About 10% presented with pain, difficulty chewing or swallowing, swelling, toothache or loose teeth, or a combination of these symptoms. Patients with LMS were much more likely to have obvious symptoms of shorter duration, and one-third presented with pain or swelling (or both). Other relatively common symptoms of LMS included tenderness, interference with dentures, or an intraoral mass. In this review, there were almost twice as many LMs as LMSs, which was consistent with smooth muscle tumors found in other areas of the gastrointestinal tract.

Early catheter removal following radical retropubic prostatectomy

Indwelling urethral catheters are bothersome for patients following radical retropubic prostatectomy. At Indiana University, to alleviate postoperative discomfort, early removal of urethral catheters has become commonplace. In our series of patients, complications were infrequent and removal improved patient mobility and reduced discomfort.

The pathology of late recurrence of testicular germ cell tumors

A total of 91 men had histologically documented late recurrences of testicular germ cell tumors characterized by a complete response to treatment with a subsequent disease-free interval of at least 2 years and no evidence of a second primary lesion. Ninety percent of the patients for whom information was available received chemotherapy shortly after their initial diagnosis of testicular germ cell tumors; most of the other patients were known to have stage I disease initially. Overall, 60% of patients had teratoma in their late recurrences, including 20 patients (22%) in whom teratoma was the only element. Thus, teratoma was the most common type of neoplasm in late recurrences. Excluding teratoma coexisting with other types of neoplasms, yolk sac tumor was the most frequent type of tumor in patients with late recurrence. It occurred in 47% of patients, either alone or with teratoma, another nonteratomatous germ cell tumor type, or a "nongerm cell malignant tumor." Unusual types of yolk sac tumor, including glandular, parietal, clear cell, and pleomorphic patterns, were seen frequently in late recurrences and often raised differential diagnostic problems with "nongerm cell" carcinomas. A smaller number of late recurrences consisted of other types of neoplasms. Twenty percent of patients with late recurrence had a nonteratomatous germ cell tumor other than yolk sac tumor, either alone, with yolk sac tumor, or with a "nongerm cell malignant tumor." Most of these nonteratomatous germ cell tumors other than yolk sac tumor were embryonal carcinoma, although rarely seminoma and choriocarcinoma were encountered. "Nongerm cell malignant tumors," including both sarcomas and carcinomas of various types, occurred in 23% of late-recurrence patients, either alone or with a nonteratomatous germ cell tumor. Late recurrences were seen in many different sites in these patients, including the retroperitoneum, abdomen, pelvis, liver, mediastinum, lung, bone (femur, vertebra, and rib), lymph nodes outside the retroperitoneum and mediastinum (supraclavicular, neck, and axillary regions), scrotum and inguinal regions, adrenal gland, chest wall, and buttocks. Follow-up data were available for 79 of the 91 patients studied. Duration of follow-up ranged from 2 months to 13 years after the patient's first late recurrences; the mean length of follow-up was 4.8 years. Patients whose late recurrences consisted of teratoma only had the most favorable outcomes, with 79% having no evidence of disease at last follow-up. Patients whose late recurrences consisted of pure "nongerm cell malignant tumor" or pure germ cell tumor (yolk sac tumor or other types) had a much worse prognosis: Only 36% to 37% were alive with no evidence of disease. Patients with two different types of nonteratomatous malignancies in their late recurrences had a dismal clinical course: Only 17% with both yolk sac tumor and other nonteratomatous germ cell tumor had no evidence of disease, whereas no patient with both nonteratomatous germ cell tumor and "nongerm cell malignant tumor" was disease free. Late recurrences consisting of teratoma alone often have a favorable outcome, but the prognosis in all other patients is poor. Furthermore, late recurrence is not likely to respond to chemotherapy and is best treated by surgical excision when possible.

Results and outcome of retroperitoneal lymph node dissection for clinical stage I embryonal carcinoma--predominant testis cancer

PURPOSE

To determine the incidence of metastatic disease and usage of chemotherapy (adjuvant or metastatic) after primary retroperitoneal lymph node dissection (RPLND) in patients with clinical stage (CS) I embryonal carcinoma (EC)-predominant testicular cancer. EC predominance was defined as the presence of EC at a level greater than that of any other histologic diagnosis.

PATIENTS AND METHODS

All CS I patients with nonseminomatous germ cell tumors who underwent RPLND at Indiana University from 1990 to 1995 were reviewed retrospectively.

RESULTS

Two-year follow-up was available for 292 of 320 patients. EC-predominant disease was found in 125 (42.8%) of 292. Eighty-five (68.0%) of 125 patients with EC-predominant disease had pathologic stage (PS) I, and 18 (21.2%) of this group of 85 relapsed. A significantly lower PS I relapse rate of 3% was found for patients who had non-EC-predominant disease (P <.0001). PS II disease was more frequent in patients with EC predominance, as 40 (32.0%) of 125 had retroperitoneal metastases, compared with 26 (15.6%) of 167 patients with a non-EC-predominant histologic diagnosis (P =.0024). Chemotherapy was administered to 48 (38.4%) of the 125 patients with CS I EC-predominant disease after RPLND. This included 25 CS I patients with PS II disease who received adjuvant chemotherapy in addition to 23 patients who subsequently required chemotherapy for relapse after RPLND. Ten (66. 6%) of 15 PS II EC-predominant patients were cured by surgery alone. Currently, all 125 EC-predominant patients are disease-free.

CONCLUSION

Patients with CS I EC-predominant disease are at a relatively high risk for metastatic disease.

Testicular cancer: what's new in staging, prognosis, and therapy

Improvements in the clinical staging of testicular cancer may permit the identification of clinical stage I patients at low risk of harboring metastatic disease, who could be spared treatment and observed only. Both retrospective, single-institution studies and studies of unselected, consecutive patients have confirmed that vascular invasion, lymphatic invasion, and percentage of embryonal carcinoma are predictive of metastasis in patients with low-stage nonseminoma. Whether patients with these risk factors have a worse outcome if managed with surveillance, rather than with aggressive therapy, is unclear. Low MIB-1 staining (which identifies the Ki-67 antigen) in conjunction with a low percentage of embryonal carcinoma in the testicular specimen appears to be predictive of a low probability of metastasis. Computed tomography (CT) is a useful staging tool. A new prognostic classification system for seminomas and nonseminomas was recently developed by an international consensus conference. Laparoscopic retroperitoneal lymphadenectomy appears to be a feasible staging tool with acceptable short-term morbidity. Whether laparoscopic lymph node dissection is equivalent to the open procedure when used as a therapeutic modality is not yet known. At present, laparoscopy should be used only in selected patients in a study setting. Primary chemotherapy is not recommended currently because it has not yet been proven to be superior in patients with high-risk clinical stage I nonseminoma and can cause significant long-term sequelae.

Expression of cyclooxygenase-2 (COX-2) in human invasive transitional cell carcinoma (TCC) of the urinary bladder

Cyclooxygenase (COX)-inhibiting drugs have antitumor activity in canine and rodent models of urinary bladder cancer. Two isoenzymes of COX have been identified, COX-1 and COX-2. The purpose of this study was to characterize COX-1 and COX-2 expression in human invasive transitional cell carcinoma of the urinary bladder by immunohistochemistry and Western blot analysis. COX-2 was not expressed in normal urinary bladder samples but was detected in 25 of 29 (86%) invasive transitional cell carcinomas of the urinary bladder and in 6 of 8 (75%) cases of carcinoma in situ. These results indicate that COX-2 may play a role in bladder cancer in humans and support further study of COX-2 inhibitors as potential antitumor agents in human bladder cancer.

Secondary tumors after initial successful treatment of metastatic testis cancer

Most patients who present with testicular cancer are cured. Because this is a disease of predominantly young men, after curative therapy these men survive for many years. In other cancers, treatment-related disease has been noted to appear many years after successful therapy. Therefore, the question of whether or not therapy-related cancers occur in testicular cancer is especially pertinent.

A Phase II study of paclitaxel and ifosfamide for patients with advanced refractory carcinoma of the urothelium

BACKGROUND

Cisplatin-based combination chemotherapy for patients with advanced transitional cell carcinoma (TCC) of the urothelium has limitations, and new therapies need to be evaluated.

METHODS

Ifosfamide 1.0 gm/m2 on Days 1-4 and paclitaxel 135 mg/m2 by 24-hour infusion on Day 4 were administered to 26 patients with locally unresectable or metastatic TCC. Cycles were repeated every 21 days for a maximum of 6 cycles; dose escalation was dependent on whether Grade 3 or 4 toxicities occurred.

RESULTS

There were 24 males and 2 females, with a median age of 66 years and a median Eastern Cooperative Oncology Group performance status of 0. The median number of cycles administered was 3. Twelve patients had Grade 3 or 4 hematologic toxicities, including 1 patient who died of a gastrointestinal hemorrhage while pancytopenic. There were no episodes of neutropenic fever. Two patients each had a complete response (CR) that lasted 5 and 28 months, respectively (response rate: 15%; 95% CI: 2-45%), among the 13 patients who had received prior chemotherapy. Of the 13 patients without prior chemotherapy, there were 3 with complete responses and 1 with a partial response ranging from 8 to 25+ months (RR: 30.7%; 95% CI: 9-61%).

CONCLUSIONS

The combination of ifosfamide and paclitaxel is well tolerated and can produce objective responses in patients who are chemonaïve or have had prior therapy. For previously untreated patients, the addition of ifosfamide does not appear to result in a better response rate than single agent paclitaxel; and for previously treated patients, the addition of paclitaxel does not appear to result in a better response rate than single agent ifosfamide.

Noninvasive surgery of prostate tissue by high intensity focused ultrasound: an updated report

OBJECTIVE

To establish clinical efficacy and safety of High Intensity Focused Ultrasound (HIFU) for the treatment of benign prostatic hyperplasia (BPH) in a multiple site clinical study.

METHODS

Seven clinical sites were set up for the studies, five in the USA, one in Canada and one in Japan respectively. Sixty two patients were enrolled in these three studies. Transrectal ultrasound probes made to produce sufficient acoustic power required for focused ultrasound surgery of the prostate as well as to perform imaging of the prostate, were employed in the study. The probes ware made of 2.5, 3.0, 3.5, 4.0 and 4.5 cm focal length transducers to treat varying prostate sizes and shapes and operated at 4 MHz frequency for both imaging and treatment. The employed ultrasound device produced both transverse and longitudinal images of the prostate on the same display. The images were used for selection of tissue volume, treatment planning and monitoring of tissue during the HIFU treatment cycle. The patients in the USA and Canada were followed for two years and those in Japan were followed for one year on a regular interval. The results were evaluated for changes in the peak flow rate (Qmax in ml/s), quality of life (QOL) and International Prostate Symptom Score (IPSS).

RESULTS

The average pre / post treatment results at 180 days were significantly different for Qmax, QOL and IPSS 8.5/14.2 (ml/s), 4.7/2.1 and 22/10 respectively.

CONCLUSION

Under this protocol, HIFU was found safe and efficacious for the treatment of BPH. The HIFU treatment produced statistically significant results for the parameters measured with least complications. Additionally, the HIFU treatment was found to be durable.

Cytogenetic analyses of 85 testicular germ cell tumors: comparison of postchemotherapy and untreated tumors

Cytogenetic analyses of 85 testicular germ cell tumors, of which 54 were karyotypically abnormal, showed recurrent breakpoints at chromosome bands 1p36, 1p13-1qh, 11q23, 19q13, and the pericentromeric regions of the acrocentric chromosomes. Postchemotherapy tumors had significantly more rearrangements of bands 3p25-p26, 6q16-q21, 8p22-p23 when compared with untreated tumors, while untreated tumors had more rearrangements of 9p22-p24 when compared with postchemotherapy tumors. Frequent breakpoints also were identified at 15q15 and 9qh in untreated tumors. Tumors of different histopathology, clinical stage, and treatment status showed no significant differences in the frequencies of i(12p)-positive and i(12p)-negative tumors.

Is retroperitoneal lymph node dissection necessary for adult paratesticular rhabdomyosarcoma?

PURPOSE

We assess the benefit of retroperitoneal lymph node dissection for adult paratesticular rhabdomyosarcoma.

MATERIALS AND METHODS

A total of 19 adults with paratesticular rhabdomyosarcoma who underwent retroperitoneal lymph node dissection between 1980 and 1997 comprise our study population. Postoperative chemotherapy was administered in all patients, including cyclophosphamide, doxorubicin and vincristine with or without consolidation with ifosfamide and etoposide in 17, and vincristine, actinomycin D and cyclophosphamide in 2. Radiation therapy also was administered in 2 patients. Patients were classified into pathological and clinical groups according to the Intergroup Rhabdomyosarcoma Studies. Mean followup was 6.4 years (range 0.5 to 17.6).

RESULTS

A total of 17 patients (89%) were disease-free and 2 (1 in pathological group I and 1 in pathological group II) died of disease that recurred outside of the retroperitoneum. Of 16 clinical group I patients 9 were in pathological group II. There were negative nodes in 2 of 3 clinical group II patients. Thus, abdominal computerized tomography correctly staged only 8 of 19 patients (42%).

CONCLUSIONS

Retroperitoneal lymph node dissection accurately stages paratesticular rhabdomyosarcoma and eliminates the need for abdominal radiotherapy in patients in pathological group II. Combined modality therapy with retroperitoneal lymph node dissection and postoperative chemotherapy achieves a high cure rate.

Is retroperitoneal lymph node dissection necessary for adult paratesticular rhabdomyosarcoma?

PURPOSE

We assess the benefit of retroperitoneal lymph node dissection for adult paratesticular rhabdomyosarcoma.

MATERIALS AND METHODS

A total of 19 adults with paratesticular rhabdomyosarcoma who underwent retroperitoneal lymph node dissection between 1980 and 1997 comprise our study population. Postoperative chemotherapy was administered in all patients, including cyclophosphamide, doxorubicin and vincristine with or without consolidation with ifosfamide and etoposide in 17, and vincristine, actinomycin D and cyclophosphamide in 2. Radiation therapy also was administered in 2 patients. Patients were classified into pathological and clinical groups according to the Intergroup Rhabdomyosarcoma Studies. Mean followup was 6.4 years (range 0.5 to 17.6).

RESULTS

A total of 17 patients (89%) were disease-free and 2 (1 in pathological group I and 1 in pathological group II) died of disease that recurred outside of the retroperitoneum. Of 16 clinical group I patients 9 were in pathological group II. There were negative nodes in 2 of 3 clinical group II patients. Thus, abdominal computerized tomography correctly staged only 8 of 19 patients (42%).

CONCLUSIONS

Retroperitoneal lymph node dissection accurately stages paratesticular rhabdomyosarcoma and eliminates the need for abdominal radiotherapy in patients in pathological group II. Combined modality therapy with retroperitoneal lymph node dissection and postoperative chemotherapy achieves a high cure rate.

Alternative strategies in the management of primary breast cancer

This article will review the current alternative strategies in the management of primary breast cancer with an emphasis on the reasons we prefer a particular strategy. We will attempt to forecast new alternatives that we expect to emerge from advances in the molecular biology of breast cancer, as well as other technological advances.

Nephroblastoma-like tumors in patients with testicular germ cell tumors

Nephroblastoma-like tumors (NLTs) developed in metastatic sites in nine men with testicular germ cell tumors (GCTs). These tumors had a characteristic "triphasic" admixture of primitive tubular structures, sometimes with a glomeruloid pattern, blastema and stroma. Skeletal muscle differentiation was apparent in two cases. Specific neuroendocrine markers (synaptophysin and chromogranin A) were negative. All patients were treated by surgical excision. Six patients were alive with no evidence of disease from 4 to 12 years after diagnosis of GCT and NLT. One patient was alive with disease 6 years after diagnosis of GCT and 3 years after diagnosis of NLT. One man who also had metastatic primitive neuroectodermal tumor (PNET) had short survival, and one patient died of postoperative infection. We conclude that patients with testicular GCTs in whom NLTs develop in metastatic sites often experience prolonged survival. Surgical excision appears to be adequate treatment for NLT arising in metastatic testicular GCT in most patients. It is important to distinguish NLTs from PNETs in metastatic GCTs because of the more aggressive course and the frequently fatal outcome of the latter.