Prognostic biomarkers for the response to the radiosensitizer nimorazole combined with RCTx: a pre-clinical trial in HNSCC xenografts.

BACKGROUND: Tumor hypoxia is associated with resistance to radiotherapy and chemotherapy. In head and neck squamous cell carcinoma (HNSCC), nimorazole, an oxygen mimic, combined with radiotherapy (RT) enabled to improve loco-regional control (LRC) in some patients with hypoxic tumors but it is unknown whether this holds also for radiochemotherapy (RCTx). Here, we investigated the impact of nimorazole combined with RCTx in HNSCC xenografts and explored molecular biomarkers for its targeted use. METHODS: Irradiations were performed with 30 fractions in 6 weeks combined with weekly cisplatin. Nimorazole was applied before each fraction, beginning with the first or after ten fractions. Effect of RCTx with or without addition of nimorazole was quantified as permanent local control after irradiation. For histological evaluation and targeted gene expression analysis, tumors were excised untreated or after ten fractions. Using quantitative image analysis, micromilieu parameters were determined. RESULTS: Nimorazole combined with RCTx significantly improved permanent local control in two tumor models, and showed a potential improvement in two additional models. In these four models, pimonidazole hypoxic volume (pHV) was significantly reduced after ten fractions of RCTx alone. Our results suggest that nimorazole combined with RCTx might improve TCR compared to RCTx alone if hypoxia is decreased during the course of RCTx but further experiments are warranted to verify this association. Differential gene expression analysis revealed 12 genes as potential for RCTx response. When evaluated in patients with HNSCC who were treated with primary RCTx, these genes were predictive for LRC. CONCLUSIONS: Nimorazole combined with RCTx improved local tumor control in some but not in all HNSCC xenografts. We identified prognostic biomarkers with the potential for translation to patients with HNSCC.

15 N NMR Hyperpolarization of Radiosensitizing Antibiotic Nimorazole by Reversible Parahydrogen Exchange in Microtesla Magnetic Fields.

Nimorazole belongs to the imidazole-based family of antibiotics to fight against anaerobic bacteria. Moreover, nimorazole is now in Phase 3 clinical trial in Europe for potential use as a hypoxia radiosensitizer for treatment of head and neck cancers. We envision the use of [15 N3 ]nimorazole as a theragnostic hypoxia contrast agent that can be potentially deployed in the next-generation MRI-LINAC systems. Herein, we report the first steps to create long-lasting (for tens of minutes) hyperpolarized state on three 15 N sites of [15 N3 ]nimorazole with T1 of up to ca. 6 minutes. The nuclear spin polarization was boosted by ca. 67000-fold at 1.4 T (corresponding to P15N of 3.2 %) by 15 N-15 N spin-relayed SABRE-SHEATH hyperpolarization technique, relying on simultaneous exchange of [15 N3 ]nimorazole and parahydrogen on polarization transfer Ir-IMes catalyst. The presented results pave the way to efficient spin-relayed SABRE-SHEATH hyperpolarization of a wide range of imidazole-based antibiotics and chemotherapeutics.

Low-energy electrons transform the nimorazole molecule into a radiosensitiser.

While matter is irradiated with highly-energetic particles, it may become chemically modified. Thereby, the reactions of free low-energy electrons (LEEs) formed as secondary particles play an important role. It is unknown to what degree and by which mechanism LEEs contribute to the action of electron-affinic radiosensitisers applied in radiotherapy of hypoxic tumours. Here we show that LEEs effectively cause the reduction of the radiosensitiser nimorazole via associative electron attachment with the cross-section exceeding most of known molecules. This supports the hypothesis that nimorazole is selectively cytotoxic to tumour cells due to reduction of the molecule as prerequisite for accumulation in the cell. In contrast, dissociative electron attachment, commonly believed to be the source of chemical activity of LEEs, represents only a minor reaction channel which is further suppressed upon hydration. Our results show that LEEs may strongly contribute to the radiosensitising effect of nimorazole via associative electron attachment.

Targeting tumour hypoxia: shifting focus from oxygen supply to demand.

Tumour hypoxia is a well-recognised barrier to anti-cancer therapy and represents one of the best validated targets in oncology. Previous attempts to tackle hypoxia have focussed primarily on increasing tumour oxygen supply; however, clinical studies using this approach have yielded only modest clinical benefit, with often significant toxicity and practical limitations. Therefore, there are currently no anti-hypoxia treatments in widespread clinical use. As an emerging alternative strategy, we discuss the relevance of inhibiting tumour oxygen metabolism to alleviate hypoxia and highlight recently initiated clinical trials using this approach.

Quality assurance of radiotherapy in the ongoing EORTC 1219-DAHANCA-29 trial for HPV/p16 negative squamous cell carcinoma of the head and neck: Results of the benchmark case procedure.

BACKGROUND AND PURPOSE: The phase III EORTC 1219-DAHANCA 29 intergroup trial evaluates the influence of nimorazole in patients with locally advanced head and neck cancer when treated with accelerated radiotherapy (RT) in combination with chemotherapy. This article describes the results of the RT Benchmark Case (BC) performed before patient inclusion. MATERIALS AND METHODS: The participating centers were asked to perform a 2-step BC, consisting of (1) a delineation and (2) a planning exercise according to the protocol guidelines. Submissions were prospectively centrally reviewed and feedback was given to the submitting centers. Sørensen-Dice similarity index (DSI) and the 95th percentile Hausdorff distance (HD) were retrospectively used to evaluate the agreement between the centers and the expert contours. RESULTS: Fifty-four submissions (34 delineation and 20 planning exercises) from 19 centers were reviewed. Nine (47%) centers needed to perform the delineation step twice and three (16%) centers 3 times before receiving an approval. An increase in DSI-value and a decrease in HD, in particular for the prophylactic Clinical Target Volume (pCTV), could be found for the resubmitted cases. No unacceptable variations could be found for the planning exercise. CONCLUSIONS: These BC-results highlight the need for effective and prospective RTQA in clinical trials. Even with clearly defined protocol guidelines, delineation and not planning remain the main reason for unacceptable protocol variations. The introduction of more objective quantitative analysis methods, such as the HD and DSI, in future trials might strengthen the evaluation by experts.

Validation of a 15-gene hypoxia classifier in head and neck cancer for prospective use in clinical trials.

BACKGROUND: In head and neck squamous cell carcinomas (HNSCC) hypoxic radioresistance can be reduced by use of the hypoxic modifier nimorazole, as shown in the DAHANCA 5 trial. Recently, a 15-gene hypoxia classifier has shown predictive impact for the effect of nimorazole by identifying 'more' and 'less' hypoxic tumors in the DAHANCA 5 cohort. A prospective multicentre EORTC-1219 study is initiated, where nimorazole and prospective use of the classifier as a predictor is tested in relation to the most recent accelerated chemoradiotherapy treatment. Validation of the gene expression classification procedures is described here. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded (FFPE) tumor material from three recent HNSCC cohorts [DAHANCA 18 (n = 96), 24 (n = 40), and IAEA Hypo (n = 55)] was used to establish and validate procedures for prospective classification of patients. Repeatability was tested for the different steps in the gene expression analysis, and reproducibility was tested with xenograft tumors (FaDuDD, UTSCC33), where gene expression in complementary sections was compared after fixation and embedding locally and at international institutions, respectively. Intra-tumor heterogeneity was addressed by classifying biopsy samples from HNSCC tumors, where 2-4 biopsies from each tumor was accessible. RESULTS: Procedures were successfully established for individual classification of HNSCC patients in retrospective and prospective cohorts. Measurements of gene expression levels were reproducible between different international institutions. CONCLUSION: Technical validation of the 15-gene hypoxia classifier demonstrated that it is suitable for implementation in prospective clinical trials.

IAEA-HypoX. A randomized multicenter study of the hypoxic radiosensitizer nimorazole concomitant with accelerated radiotherapy in head and neck squamous cell carcinoma.

PURPOSE: To test the hypothesis that radiotherapy (RT) of head and neck squamous cell carcinoma (HNSCC) can be improved by hypoxic modification using nimorazole (NIM) in association with accelerated fractionation. MATERIALS AND METHODS: The protocol was activated in March 2012 as an international multicenter randomized trial in patients with HNSCC. Tumors were treated to a dose of 66-70Gy, 33-35 fractions, 6 fractions per week. NIM was administered in a dose of 1.2gperm(2), 90min before the first daily RT fraction. The primary endpoint was loco-regional failure. The trial was closed prematurely by June 2014 due to poor recruitment. An associated quality assurance program was performed to ensure the consistency of RT with the protocol guidelines. RESULTS: The trial was dimensioned to include 600 patients in 3years, but only 104 patients were randomized between March 2012 and May 2014 due to the inability to involve three major centers and the insufficient recruitment rate from the other participating centers. Twenty patients from two centers had to be excluded from the analysis due to the unavailability of the follow-up data. Among the remaining 84 patients, 82 patients were evaluable (39 and 43 patients in the RT+NIM and the RT-alone arms, respectively). The treatment compliance was good with only six patients not completing the full planned RT course, and 31 patients (79%) out of 39 allocated for NIM, achieving at least 90% of the prescribed drug dose. At the time of evaluation, 40 patients had failed to achieve persistent loco-regional tumor control, and a total of 45 patients had died. The use of NIM improved the loco-regional tumor control with an 18month post-randomization cumulative failure rate of 33% versus 51% in the control arm, yielding a risk difference of 18% (CI -3% to 39%; P=0.10). The corresponding values for overall death was 43% versus 62%, yielding a risk difference of 19% (CI -3% to 42%; P=0.10). Sixteen patients, out of 55 patients analyzed for hypoxic gene expression, were classified as having more hypoxic tumors. Such patients, if treated with RT alone, had a higher loco-regional tumor failure rate as compared to the rest of the patients with known hypoxic status (P=0.05). CONCLUSION: Although the trial was incomplete and suffered from a small number of patients, the results suggested an improvement in loco-regional tumor control and overall survival in patients with advanced HNSCC given the hypoxic modifier NIM in addition to accelerated fractionation RT. However, the trial also revealed that conducting multicenter and multinational study combining drug and RT in developing countries may suffer from uncontrolled and unsolvable problems.

Gene expression classifier predicts for hypoxic modification of radiotherapy with nimorazole in squamous cell carcinomas of the head and neck.

PURPOSE: To validate the predictive impact of a hypoxia gene expression classifier in identifying patients with head and neck squamous cell carcinoma (HNSCC) having benefit from hypoxic modification of radiotherapy. PATIENTS AND METHODS: Gene expressions were quantified from formalin-fixed, paraffin-embedded tumour biopsies of 323 HNSCC patients randomized for placebo or nimorazole in conjunction with radiotherapy in the DAHANCA 5 study. Tumours were classified as either "more" or "less" hypoxic with a classifier constituting of 15 hypoxia responsive genes. The predictive impact was evaluated by analysing the response to nimorazole vs. placebo in terms of loco-regional tumour control (LRC) and disease-specific survival (DSS) in the two classified groups. RESULTS: Hundred and fourteen patients (35%) were classified as having "more" hypoxic tumours. These patients had a significant benefit of hypoxic modification with nimorazole compared with placebo in terms of LRC (5-year actuarial values 49% vs. 18%; p=0.001) and DSS (48% vs. 30%; p=0.04). "Less" hypoxic tumours had no significant effect of hypoxic modification (LRC: 50% vs. 44%; p=0.39, DSS: 57% vs. 51%; p=0.49) and generally an outcome, which was similar to "more" hypoxic tumours treated with nimorazole. In contrast to HPV-negative tumours, HPV-positive tumours had a substantially better outcome in response to radiotherapy, which was irrespective of hypoxic modification. CONCLUSIONS: A predictive 15-gene hypoxia classifier could identify patients associated with improved outcome after combining radiotherapy with hypoxic modification and underlines the relevance of such therapy. The impact of the classifier was limited to HPV-negative tumours.

Does transfusion improve the outcome for HNSCC patients treated with radiotherapy? - results from the randomized DAHANCA 5 and 7 trials.

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) and a low level of hemoglobin often have a poor response to radiation that may be related to hypoxia-induced radioresistance. We have previously published the importance of hemoglobin level and the effect of transfusion by the results from the randomized DAHANCA 5 trial, including 414 patients in the analysis. Aim of the current analysis was to gain additional power by adding patients from the continued subrandomization in the DAHANCA 7 trial, now including a total of almost 1200 patients. MATERIAL AND METHODS: Patients were randomized to treatment in the DAHANCA 5 and 7 study (nimorazole vs. placebo and five fx/week vs. six fx/week), and in addition, patients with "low" pre-irradiation hemoglobin values (females <13 g/dl; males <14.5 g/dl) were subrandomized to plus or minus transfusion. Transfusion was given with packed red blood cells with the aim to achieve a hemoglobin level in the "high" value range. RESULTS: A total of 1166 patients were included, 701 patients had high hemoglobin levels and 465 had low hemoglobin levels. Among the low hemoglobin patients, 235 were randomized to receive transfusion. Patient characteristics and treatment arms were well balanced. In the majority of patients, transfusion resulted in increased hemoglobin levels although this decreased slightly throughout treatment as in the non-transfused patients. Overall, the patients with low hemoglobin level had a significant reduced probability of locoregional control, disease-specific and overall survival. In the low hemoglobin group, transfusion did not improve the outcome in locoregional control, disease-specific or overall survival. In multivariate analyses, HPV/p16 status, T and N classification were significant factors for all outcome measures, whereas there was no significant influence of transfusion or hemoglobin level on endpoints. CONCLUSION: Transfusion prior to and during radiation treatment did not improve the outcome in patients with HNSCC and low hemoglobin values, but may have a negative impact on survival.

Evidence-based radiation oncology in head and neck squamous cell carcinoma.

BACKGROUND AND PURPOSE: Historically, radiation therapy (RT) has been an available treatment option for patients with early resectable head and neck squamous cell carcinoma (HNSCC) and the sole therapy for those with unresectable or inoperable disease. Recently, four noteworthy strategies have emerged for the improvement of therapeutic outcome in the curative treatment of HNSCC: they include the development of altered fractionation radiotherapy, integration of chemotherapy with radiotherapy, incorporation of intensity-modulated radiotherapy and the introduction of targeted biological therapy. These strategies are briefly reviewed in an effort to help interpret evidence-based data and to facilitate clinical-decision making in a clinical context. MATERIALS AND METHODS: For patients with early stage HNSCC no level 1 study exists in which radiation therapy is compared with conservative surgery for the evaluation of local control or survival. Only evidence from prospective and retrospective cohort studies is available to evaluate the role external radiotherapy and/or brachytherapy currently play in limited disease. For patients with locally advanced HNSCC the recommendations to address the questions about better treatment in resectable and unresectable tumors are based on more than 100 randomized Phase III trials included in six meta-analyses on chemo-radiotherapy and/or altered fractionation. Data from phase II trials and cohort studies help interpret the advances in intensity-modulated radiotherapy. RESULTS: External radiotherapy and/or brachytherapy are crucial treatment options in patients with early stage HNSCC. For patients with locally advanced HNSCC, where outcome with conventional radiotherapy is poor, meta-analyses and collective data showed that loco-regional control may be improved at high level of evidence by altered fractionation radiotherapy, chemo-radiotherapy with concomitant approach or association of selected hypoxic cell radiosensitizer with radiotherapy. For these patients, overall survival may be improved at high level of evidence by concomitant chemo-radiotherapy or hyperfractionated RT delivered with increased total dose. Also EGFR-inhibitors (cetuximab)-radiotherapy strategy offers at a lower level of evidence better loco-regional control and overall survival than radiotherapy alone. Chemo-radiotherapy programs can achieve an improved larynx-function preservation program without the risk of overall survival reduction, for patients with larynx or hypopharynx tumors who are candidates to radical surgery followed by radiotherapy. Recently, strong evidence for an improved outcome for high-risk resected patients has been shown by the use of adjuvant concomitant chemo-radiotherapy. Despite improved results, a higher severe toxicity has been largely evidenced with concomitant chemo-radiotherapy by reducing the gain in the therapeutic index with new treatment strategies. Three-dimensional conformal radiotherapy is the minimal standard of technique in HNSCC: however, as advances are promising, intensity-modulated radiotherapy should be largely implemented. CONCLUSIONS: Stepwise improvements in HNSCC non-surgical therapy have shown favorable impact on loco-regional control and overall survival. However, despite hundreds of clinical trials in patients with advanced disease, there is no absolute consensus about patient selection for altered fractionation regimens, type of chemo-radiotherapy association, radiation or chemotherapy dose schedule. Nevertheless, many well-conducted clinical studies have expanded therapy options besides standard radiotherapy and have contributed to defining the evolving standard of care for patients with HNSCC.

Five compared with six fractions per week of conventional radiotherapy of squamous-cell carcinoma of head and neck: DAHANCA 6 and 7 randomised controlled trial.

BACKGROUND: Although head and neck cancer can be cured by radiotherapy, the optimum treatment time for locoregional control is unclear. We aimed to find out whether shortening of treatment time by use of six instead of five radiotherapy fractions per week improves the tumour response in squamous-cell carcinoma. METHODS: We did a multicentre, controlled, randomised trial. Between January, 1992, and December, 1999, of 1485 patients treated with primary radiotherapy alone, 1476 eligible patients were randomly assigned five (n=726) or six (n=750) fractions per week at the same total dose and fraction number (66-68 Gy in 33-34 fractions to all tumour sites except well-differentiated T1 glottic tumours, which were treated with 62 Gy). All patients, except those with glottic cancers, also received the hypoxic radiosensitiser nimorazole. Analysis was by intention to treat. FINDINGS: More than 97% of the patients received the planned total dose. Median overall treatment times were 39 days (six-fraction group) and 46 days (five-fraction group). Overall 5-year locoregional control rates were 70% and 60% for the six-fraction and five-fraction groups, respectively (p=0.0005). The whole benefit of shortening of treatment time was seen for primary tumour control (76 vs 64% for six and five fractions, p=0.0001), but was non-significant for neck-node control. Six compared with five fractions per week improved preservation of the voice among patients with laryngeal cancer (80 vs 68%, p=0.007). Disease-specific survival improved (73 vs 66% for six and five fractions, p=0.01) but not overall survival. Acute morbidity was significantly more frequent with six than with five fractions, but was transient. INTERPRETATION: The shortening of overall treatment time by increase of the weekly number of fractions is beneficial in patients with head and neck cancer. The six-fractions-weekly regimen has become the standard treatment in Denmark.

[Contribution of radiation biology to the development of radiation therapy].

Results of radiation therapy for malignant tumors have steadily improved, and both radiation biology and radiation physics have contributed to this improvement. As examples of such contribution, radiobiologically-elaborated continuous hyperfractionated accelerated radiotherapy (CHART) has been proven to be superior to conventional radiotherapy against non-small cell lung cancer, and a hypoxic cell sensitizer nimorazole has been proven to be effective against pharyngeal and supraglottic laryngeal cancers. Based on laboratory studies, a combination of chemotherapy and radiotherapy has been shown to be superior to radiotherapy alone in many cancers. Radiation biology has also provided important fundamental data for clinical applications of heavy ion and proton beam therapy. In the future, useful predictive assays and radioprotectors are also expected to be developed. Radiation biology should continue to contribute to the further development of clinical radiation therapy.

Pilot study of nimorazole as a hypoxic-cell sensitizer with the "chart" regimen in head and neck cancer.

PURPOSE: A potential disadvantage of accelerated fractionation in radiotherapy is the lack of time for reoxygenation, so that hypoxia becomes a more potent cause of failure. Accordingly, we have combined nimorazole, the only hypoxic radiosensitizer shown to significantly improve local control in head and neck cancer, with continuous hyperfractionated accelerated radiation therapy (CHART). METHODS AND MATERIALS: Twenty-two patients with locally advanced (stage IV) squamous cell carcinoma of the head and neck were treated with escalating doses of nimorazole given concomitantly with CHART (three fractions of 1.5 Gy per day, spaced 5 1/2 hours apart, on 12 consecutive days). All patients received 1.2 g/m2 nimorazole 90 minutes before each first daily fraction. Seventeen patients received a further 0.6 g/m2 before each second daily fraction and six of these patients received an additional dose of 0.6 g/m2 before each third fraction. RESULTS: The three times daily schedule yielded mean plasma drug concentrations at the time of irradiation of 37.7 microg/ml with the morning fractions, 31.2 microg/ml with the afternoon fractions, and 30.4 microg/ml with the evening fractions. In view of these results the midday dose was increased to 0.9 microg/m2 in an ongoing Phase II study. Drug toxicity was limited to nausea and vomiting apart from two cases of mild paraesthesia at the highest dose level. CONCLUSIONS: Comparison with a historical group of patients, treated with the CHART regimen alone and matched for irradiation volume and technique, showed that nimorazole did not increase the severity of acute normal tissue radiation effects. Encouraging tumor responses have been seen in the patients receiving nimorazole with every radiotherapy fraction.

A randomized double-blind phase III study of nimorazole as a hypoxic radiosensitizer of primary radiotherapy in supraglottic larynx and pharynx carcinoma. Results of the Danish Head and Neck Cancer Study (DAHANCA) Protocol 5-85.

PURPOSE: A multicenter randomized and balanced double-blind trial with the objective of assessing the efficacy and tolerance of nimorazole given as a hypoxic radiosensitizer in conjunction with primary radiotherapy of invasive carcinoma of the supraglottic larynx and pharynx. PATIENTS AND TREATMENT: Between January 1986 and September 1990, 422 patients (414 eligible) with pharynx and supraglottic larynx carcinoma were double-blind randomized to receive the hypoxic cell radiosensitizer nimorazole, or placebo, in association with conventional primary radiotherapy (62-68 Gy, 2 Gy per fraction, five fractions per week). The median observation time was 112 months. RESULTS: Univariate analysis showed that the outcome (5-year actuarial loco-regional tumor control) was significantly related to T-classification (T1-T2 48% versus T3-T4 36%, P = 0.0008), neck-nodes (N- 53% versus N+ 33%), pre-irradiation hemoglobin (Hb) concentration (high 46% versus low 37%, P = 0.02) and sex (females 51% versus males 38%, P = 0.03). Overall the nimorazole group showed a significantly better loco-regional control rate than the placebo group (49 versus 33%, P = 0.002). A similar significant benefit of nimorazole was observed for the end-points of final loco-regional control (including surgical salvage) and cancer-related deaths (52 versus 41%, P = 0.002). This trend was also found in the overall survival but to a lesser, non-significant extent (26 versus 16%, 10-year actuarial values, P = 0.32). Cox multivariate regression analysis showed the most important prognostic parameters for loco-regional control to be positive neck nodes (relative risk 1.84 (1.38-2.45)), T3-T4 tumor (relative risk 1.65 (1.25-2.17)) and nimorazole (relative risk 0.69 (0.52-0.90)). The same parameters were also significantly related to the probability of dying from cancer. The compliance to radiotherapy was good and 98% of the patients received the planned dose. Late radiation-related morbidity was observed in 10% of the patients, irrespective of nimorazole treatment. Drug-related side-effects were minor and tolerable with transient nausea and vomiting being the most frequent complications. CONCLUSION: Nimorazole significantly improves the effect of radiotherapeutic management of supraglottic and pharynx tumors and can be given without major side-effects.

A gardnerellose clínica / Clinical gardnerella infection

Os autores estudaram um grupo de 492 mulheres adultas, näo grávidas, todas em clínica privada e que haviam se queixado, basicamente, de corrimento com odor fétido. A hipótese de contaminaçäo vaginal por Gardnerella foi levantada e confirmada através de colposcopia (fina colpite), colpocitologia e bacterioscopia do conteúdo vaginal. Do grupo em estudo, 117 pacientes receberam o mesmo tratamento com dose única de 2g de nimorazol VO (casal) e 10 comprimidos vaginais contendo nimorazol, cloranfenicol e nistatina. Um dos critérios de cura foi clínico, pela constataçäo do desaparecimento do sintoma maior: o odor fétido. No grupo tratado, obtivemos 63, 24 por cento de cura, sendo que 36, 75 por cento das pacientes do grupo de 117 foram tratadas mas näo voltaram para o diagnóstico citológico de cura. O presente estudo visa chamar a atençäo do médico para a gardnerellose como DST, valorizando a queixa de odor fétido nas secreçöes genitais, já que ela estava presente em 100 por cento das pacientes em estudo.

A gardnerellose clínica / The clinical gardnerellosis

Os autores estudaram um grupo de 492 mulheres adultas näo-grávidas, todoas em clínicas privada e que haviam se queixado, basicamente, de corrimento com odor fétido. A hipótese de contaminaçäo vaginal por Gardnerella foi levantada e confirmada através de colposcopia (fina colpite), colpocitologia e bacteriosocpia do conteúdo vaginal. Do grupo em estudo, 117 pacientes receberam o mesmo tratamento com dose única de 2g de nimorazol DO (casal) e 10 comprimidos vaginais contendo nimorazol, cloranfenicol e nistatina. Um dos critérios de cura foi clínico, pela constataçäo do desaparecimento do sintoma maior, o odor fétido. No grupo tratado, obtivemos 63,24 por cento de cura, sendo que 36,75 por cento das pacientes do grupo de 117 foram tratadas mas näo voltaram para o diagnóstico citológico de cura. O presente estudo visa chamar a atençäo do médico para as gardnerellosoe como DST, valorizando a queixa de odor fétido nas secreçöes genitais, já que ela estava presente em 100 por cento das pacientes em estudo.