Phase II study on the combination carboplatin-celecoxib in heavily pre-treated recurrent ovarian carcinoma patients

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Background: Cyclooxygenase-2 (COX-2) has been shown to be involved in several steps of ovarian onset and progression and its overepression is associated with a poor chance of response to chemotherapy and poor prognosis in ovarian cancer. Celecoxib, an orally active selective COX-2 inhibitor, has been tested for its ability to potentiate the activity of carboplatin in treatment of heavily pretreated recurrent ovarian cancer patients. Methods: A phase II study was planned, considering the regimen active if at least 12 responses were observed among the 43 enrolled patients. Celecoxib (400 mg/die), and carboplatin (5 AUC) q28 were administered, until progression or unacceptable toxicity. Response was assessed by RECIST and also by Rustin criteria. Results: 34 pts (median age: 60 yrs, range 28–74) and an ECOG performance status (0/1/2) of (21/12/1), were enrolled. 58.8% of patients were platinum resistant (progressing during or < 6 months from primary treatment). Median number of previous chemotherapy regimens was 3 (range 2–6). Currently 27 patients are evaluable for response. The overall response rate (CR and PR) was 25.9% (2 CR, 5 PR) with stabilization of disease in 8 patients (29.6%). Four responses occurred in platinum sensitive and 3 in platinum resistant group Median time to response was 11 weeks (range 9–19) and median duration of response was 23 weeks (range 12–39). According to Rustin criteria 10 patients out of 25 (40%) were considered responsive to treatment (return of CA125 levels to normal level or >50% reduction). Overall, 143 cycles were administered with a median value of 3 cycles (range = 1–10). Moderate/severe toxicities were as follows: G3 anemia occurred in 2.3% cycles, G3 neutropenia in 4.6% cycles, G3 thrombocytopenia in 1.5% cycles, G3/4 gastrointestinal toxicity occurred in 4.6% cycles. Cutaneous diffuse erithema was observed in 2 patients, in both cases recovered with a short period of antihistaminic treatment; 2 cases of hypertension were documented, G2 hypersensitivity reactions during carboplatin infusion were observed in 4 cases. Conclusions: Celecoxib combined with carboplatin is well tolerated and has promising activity as salvage treatment in heavily pretreated recurrent ovarian cancer patients.

No significant financial relationships to disclose.

A multicentre, prospective phase 2 study of weekly schedule of carboplatin (C) plus paclitaxel (P) in first-line treatment of elderly patients (pts) with ovarian cancer (OC). The MITO (Multicentre Italian Trials in Ovarian cancer)-5 study

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Background: CP every 3 weeks is the standard for pts with OC, but elderly pts frequently receive modified schedules or single agent chemotherapy to avoid toxicity. A prospective phase 2 study was conducted to describe tolerability and activity of a weekly schedule of CP in elderly pts with OC. Methods: Pts aged ≥70 years with chemo-naive OC, stage IC-IV, ECOG PS≤2 were eligible. Treatment was C (AUC 2) + P (60 mg/m2) on days 1, 8, 15 every 4 weeks, up to 6 cycles. A 2-stage minimax design was applied. With rate of pts without unacceptable toxicity in the first 3 cycles (UT) as primary endpoint, alpha 0.05 and beta 0.10, p0=0.75, p1=0.95, ≥23/26 pts without UT were required at the final stage. Toxicity was coded with NCI-CTC and response by RECIST. Geriatric assessment was performed by ADL (Activities of Daily Living) and IADL (Instrumental ADL). Results: 26 pts were enrolled. Median age was 77 (range 70–84). PS0: 10 pts, PS1: 16 pts. 14 pts (53.8%) had ≥2 comorbidities. 32%/72% had some ADL/ IADL dependency, respectively. 23 pts (88.5%) did not suffer UT. The 3 UT recorded were g3 heart rhythm (1 pt), g3 liver (1 pt), prolonged haematological toxicity (1 pt). Other main toxicities: g3 thrombocytopenia 1 pt, g2 constipation 2 pts (8%), g1 neuropathy 4 pts (15%). Out of 13 pts with at least one measurable lesion, 4 partial responses were observed (response rate 30.8%, 95% exact CI: 9.1–61.4). Out of 6 pts with non-measurable disease and 2 pts evaluable only for Ca125, 4 complete responses were observed (50%). Conclusions: In this series of elderly OC pts, characterized by a high incidence of comorbidities and functional impairment, weekly CP has a favourable toxicity profile. In this setting, a comparison of weekly vs 3-weekly CP is advisable to compare efficacy.

No significant financial relationships to disclose.

Phase II study of oxaliplatin (OXA) and docetaxel (DTX) in recurrent ovarian cancer

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Background: We conducted a phase II study to evaluate the efficacy and safety of OXA and DTX in recurrent platinum-sensitive ovarian cancer patients. Methods: Patients received DTX 75 mg/m2 (60-min i.v.) on day 1, followed by OXA 100 mg/ m2 (120-min i.v.) on day 1 every 21 days. Results: Between October 2002 and November 2005, 30 Caucasian patients (median age: 53.5 yrs; range, 31–73) were enrolled; 7 (23.3%) patients had FIGO stage I-II disease, 22 (73.3%) had FIGO stage III, and 1 (3.3%) had FIGO stage IV disease. Sites of relapse were as follows: abdominal 3 (10.0%), pelvis 5 (16.7%), lymph nodes 10 (33.3%), peritoneal 7 (23.3%), lung 1 (3.3%), and mixed 4 (13.3%). The median PFI was 28.5 months (range 13–91). The median CA125 was 182 U/ml (range 21–5,596 U/ml). Of the 30 patients evaluable, 13 (43.3%) had complete responses and 7 (23.3%) had partial responses, for an overall response rate of 66.6%. The median time to response was 9.5 wks (range 5–32) and the median duration of response was 43 wks (range 5–124). 8 (26.7%) patients had stable disease (median duration of stabilization: 26.5 wks, range 12–43). 2 (6.7%) patients progressed while on treatment. An overall clinical benefit was observed in 93.3% of patients. All patients were evaluable for toxicity. A total of 186 courses were given, with a median of 6 cycles per patient (range 2–11). Severe toxicities (Grade 3–4 NCI-CTC) included: neutropenia in 29.4% of cycles; severe anemia and thrombocytopenia were not observed. Grade 3–4 neurotoxicity and alopecia were detected in 2.8% and 22.8% of cycles respectively. Allergic reaction was observed only in one case. Doses were reduced by 20% in 14.0% of cycles. Conclusions: In recurrent platinum-sensitive ovarian cancer patients the OXA/DTX combination is highly active with acceptable toxicity, thus making it an attractive regimen.

No significant financial relationships to disclose.

From bio-molecular and technology innovations to clinical practice: focus on ovarian cancer

Ovarian cancer (OC) still represents the most lethal of gynecological malignancies with the chance for death in 5 years exceeding the chance for life. In recent years, the development of knowledge in molecular biology of OC coupled with the new technologies offers enormous opportunity to learn about aetiology of OC, and also give us a powerful tool for early diagnosis, prognosis and treatment of this disease. In particular, small cancer specimens from patients have become extremely informative thanks to techniques such as laser capture microdissection (LCM), tissue lysate arrays (TLAs), reverse trascriptase polymerase chain reaction (RT-PCR), and mass spectrometry. All of this coupled with advancements in bioinformatics have allowed the explosion of genomics, transcriptomics and proteomics. This paper focusses on the influence that advancement in the "-omics" bio-technology will reserve in OC diagnosis, prognostic characterization, and treatment.

Ultrasound and color power Doppler in the detection of metastatic omentum: a prospective study

OBJECTIVES

To analyze prospectively the ability of ultrasound to detect metastatic omentum in patients with suspicious pelvic masses and to describe the sonographic features of metastatic omental disease.

METHODS

One hundred and eighty-four patients were evaluated preoperatively by ultrasound examination and of these 173 were used in the analysis. We defined as an ultrasound-positive examination one which visualized intra-abdominal aperistaltic solid tissue, located above the bowel loops and below the anterior peritoneal surface. Preoperative sonographic findings were compared with pathological results.

RESULTS

Sonographic detection of metastatic omentum was achieved in 104 of 173 patients (60.1%), appearing as either solid aperistaltic tissue (80.8% of cases), or as solid discrete nodules (19.2%). When considering the echostructure of the surrounding bowel loops, this tissue appeared hypoechoic in 46 (44.2%) cases and isoechoic or slightly hyperechoic in the other 58 (55.8%) cases. In the overall series, the negative and positive predictive values (NPV and PPV) and the accuracy of ultrasound examination were 92.7%, 91.3% and 91.9%, respectively. When considering only the group of ovarian tumors, the NPV, PPV and accuracy were 91.9%, 94.6%, and 93.8%, respectively.

CONCLUSION

Ultrasound examination is highly accurate in detecting metastatic omental involvement in cases with suspicious pelvic masses.

Gemcitabine in epithelial ovarian cancer treatment: current role and future perspectives

Newer agents and combinations are needed in order to improve current results in ovarian cancer treatment. Gemcitabine is a novel agent that has shown consistent activity as a single agent in the treatment of platinum-resistant ovarian cancer and a favorable toxicity profile. Because of its clinical and preclinical synergism with platinum analogs, gemcitabine has been combined with carboplatin as a convincing approach in the treatment of platinum-sensitive recurrent ovarian cancer patients. Further combination of gemcitabine and other agents, including paclitaxel, is also feasible and has been actively studied in order to establish the role of gemcitabine in the management of treated and untreated ovarian cancer patients.

Ultrasound features of different histopathological subtypes of borderline ovarian tumors

OBJECTIVE

To describe the gray-scale sonographic and color Doppler imaging features of the most common histopathological subtypes of borderline ovarian tumors.

METHODS

We analyzed retrospectively the preoperative transvaginal sonographic reports of patients with a histological diagnosis of borderline ovarian tumor. All patients were scanned consecutively by two of the investigators using transabdominal and transvaginal gray-scale imaging to assess the morphology and color Doppler to obtain indices of the blood flow. Sonographic findings were compared to histopathological data.

RESULTS

A total of 113 consecutive cases were reviewed from two referral centers for gynecological oncology. At histological examination 50 tumors (44%) were classified as being serous borderline ovarian tumors (SBOT), 61 (54%) were mucinous borderline ovarian tumors (MBOT) (42 intestinal type and 19 endocervical type), and two patients (2%) presented with borderline endometrioid tumors. SBOTs and endocervical-type MBOTs had very similar sonographic features and a smaller diameter, fewer locules (usually unilocular-solid lesions) and a higher color score than intestinal-type MBOTs. Intestinal-type MBOTs were characterized by a significantly higher percentage of lesions with > 10 locules when compared with the endocervical-type MBOTs.

CONCLUSION

Intestinal-type MBOTs have different sonographic features from other common borderline ovarian tumors.

Progression of conservatively treated endometrial carcinoma after full term pregnancy: A case report

INTRODUCTION

We describe a case of conservatively treated endometrial endometrioid (EE) adenocarcinoma which showed an aggressive clinical outcome after pregnancy.

CASE

A 30-year-old woman with a well differentiated EE adenocarcinoma decided to attempt a conservative approach and underwent progestin treatment with subsequent negative ultrasound and hysteroscopic controls. After 3 months, she conceived and at 36 weeks of gestation, a cesarean section was performed with multiple negative biopsies. Eight 8 months after delivery, an exploratory laparotomy documented disseminated poorly differentiated EE adenocarcinoma. Staging work up revealed diffuse metastatic disease. Despite chemotherapy, the patient experienced progression of disease with fatal acute respiratory syndrome due to massive neoplastic pulmonary lymphangitis.

CONCLUSION

Conservative medical management of endometrial cancer in young women willing to preserve their reproductive potential, carries on potential risks. Careful selection of cases, informed consent, and strict follow up procedures are mandatory.

Skull metastasis in primary vulvar adenocarcinoma of the Bartholin's gland: A case report

BACKGROUND

Metastatic bone involvement in vulvar squamous carcinoma is very rare. Here, we present a case of primary adenocarcinoma of the Bartholin's gland giving rise to isolated skull metastasis.

CASE

A 74-year-old woman was referred with a diagnosis of primary vulvar adenocarcinoma of the right labium minus. A right hemivulvectomy was performed with ipsilateral inguinofemoral lymphadenectomy, revealing a primary adenocarcinoma of the Bartholin's gland and metastatic involvement in 6 out of 13 lymphnodes. During chemotherapy administration, the patient started complaining of a worsening of right hypoacousis. CT scan and MRI of the brain showed the presence of a metastatic lesion on the right side of the skullbone. The diagnosis was metastatic poorly differentiated adenocarcinoma.

CONCLUSION

In adenocarcinoma of the Bartholin's gland at an advanced stage of disease, a bone scan or survey in the preoperative as well as follow up staging procedures could be useful.

Does quantitative analysis of three-dimensional power Doppler angiography have a role in the diagnosis of malignant pelvic solid tumors? A preliminary study

OBJECTIVE

To investigate the role of a simplified method for the three-dimensional (3D) quantification of tumor vascularity in the differential diagnosis of solid pelvic masses.

METHODS

Twenty-four patients with a solid pelvic mass on B-mode ultrasound evaluation underwent 3D power Doppler evaluation before surgery. The volume of interest was obtained by drawing the largest section of the mass in three orthogonal planes. The following 3D vascular parameters were calculated for all patients: relative color, average color and flow measure. Receiver-operating characteristics curve analysis was used to choose the best cut-off value. The overall agreement between the test result and the actual outcome was calculated using kappa statistics.

RESULTS

Fifteen of 24 subjects were found to have pelvic malignancy. The relative color and the flow measure were significantly higher in malignant (9.7 (8.98) and 8.95 (8.78) (median (interquartile range (IQR)), respectively) than in benign masses (2 (4.42) and 1.79 (4.71), respectively; P < 0.05) but there was no difference in the average color. The best cut-off values of relative color and flow measure were 3.2 and 2.8, respectively. The use of relative color showed a sensitivity of 80% with a specificity of 67% with an overall agreement that was higher, though only marginally so, than that of qualitative 3D power Doppler (kappa = 0.47 and 0.44, respectively).

CONCLUSIONS

In a small group of pelvic masses that appear malignant on B-mode ultrasonography, the use of 3D quantification of tumor vascularity yields a diagnostic accuracy that is similar to that of subjective evaluation of vascularity. We suspect, however, that the quantitative method will produce more consistent results between operators.

Role of pegylated liposomal doxorubicin (PLD) in epithelial ovarian cancer

Pegylated liposomal doxorubicin (PLD, Caelyx) is an emerging option for patients with recurrent ovarian carcinoma. Several phase II studies showed promising activity of PLD in recurrent ovarian cancer patients with response rate ranging from 16 to 25%. A phase III randomized trial compared PLD 50 mg/m2 day 1 every 4 weeks with Topotecan 1.5 mg/m2 daily for 5 days q 21 in recurrent ovarian cancer patients. No differences in progression free survival and overall survival were documented between treatment arms in the general population but a survival advantage was reported for platinum-sensitive subset. Our experience with PLD in the treatment of ovarian cancer is reported in this review article. Pegylated liposomal doxorubicin is effective as a second line treatment in ovarian cancer patients; comparative data are needed to establish its role in first line therapy.

Survivin expression in ovarian cancer and its correlation with clinico-pathological, surgical and apoptosis-related parameters

We investigated the association of survivin expression with prognosis and other apoptosis-related biological factors in 110 primary ovarian cancer patients admitted to the Division of Gynecologic Oncology, Catholic University of Rome. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections by using polyclonal antibody ab469 for survivin, and mouse monoclonal antibodies (clone 124 and DO-7), for bcl-2 and p53, respectively. Cytoplasmic survivin immunoreaction was observed in 84.5% cases, while nuclear survivin immunostaining was observed in 29.1% cases. We failed to find any relationship between cytoplasmic survivin positivity rate and any of the parameters examined. Serous tumours showed a lower percentage of nuclear survivin positivity with respect to other histotypes (20.5 vs 48.6%, respectively; P-value=0.004). The percentage of nuclear survivin positivity was higher in cases subjected to primary tumour cytoreduction (43.5%), with respect to patients subjected to exploratory laparotomy (20%) (P=0.024). Bcl-2 and p53 were, respectively, expressed in 27.3 and 60.0% of the cases and their expression was not correlated with survivin status. During the follow-up period, progression and death of disease were observed in 68 (61.8%) and 53 (48.2%) cases, respectively. There was no difference in time to progression and overall survival according to survivin status in ovarian cancer patients. In conclusion, in our experience, the immunohistochemical assessment of survivin status does not seem to be helpful in the prognostic characterisation of ovarian cancer. A more in depth investigation of the complex physiology of divergent survivin variants is needed in order to clarify the biological and the clinical role of differentially located survivin isoforms.

Stem cell-based treatments for gynecological solid tumors

BACKGROUND AND OBJECTIVE

We have recently assisted to an increasing scientific interest and a new research effort in the field of stem cell-based therapy. Since the late 1980s hematopoietic stem cells (HSC) have been used to set up therapeutic strategies for the treatment of solid tumors such as gynecological cancers. In this context, different approaches have been suggested and clinically investigated.

STATE OF THE ART

In the autologous setting we can describe the well-known use of HSC as hematologic support to high-dose chemotherapy regimens, and the use of HSC as a source of dendritic cells for cancer vaccination protocols. In our institution a long-term experience has been developed in high-dose chemotherapy with autologous HSC transplantation as first-line treatment of advanced ovarian cancer, and in the use of cytokines both for HSC collection and for post-transplantation hematopoietic recovery and immune reconstitution. An alternative approach consists of allogenic HSC transplantation following either myeloablative/standard or non-myeloablative/reduced conditioning regimens, which have been proposed as new adoptive immunotherapeutic treatments for different non-hematologic malignancies.

PERSPECTIVES

Future strategies in the use of HSC in oncology comprise the possibility of HSC ex-vivo expansion, the use of umbilical cord blood HSC, and the development of HSC-based gene-therapy programs. Further investigations are expected in the new field of cancer stem cells.

Microsatellite instability is not related to response to cisplatin-based chemotherapy in cervical cancer

This study investigates whether microsatellite instability (MSI) due to defects of the mismatch repair (MMR) system could be associated with response to cisplatin-based neoadjuvant chemotherapy (NACT) and if cisplatin exposure could select MSI-positive cell clones in cervical cancer. Microsatellite analysis was performed by polymerase chain reactions using six microsatellite markers, while hMLH1 protein expression was investigated by immunohistochemistry. We found that 1 tumor out of 20 (5%) NACT-responding patients and 1 tumor out of 18 (6%) nonresponding patients showed MSI. The analysis of tumor specimens collected after NACT revealed no change in the banding pattern as compared to each corresponding pre-NACT tumor at each locus tested. hMLH1 staining was observed in at least > or =80% of cells in all tumors examined except the two exhibiting MSI. Our data showed that MSI due to defects of the MMR system seems not to play a crucial role in the biology of human cervical cancer cells and that MSI seems not to be related to response to chemotherapy. Moreover, cisplatin exposure did not seem to select for MMR-deficient tumor clones in cervical cancer.

Microsatellite instability is not related to response to cisplatin-based chemotherapy in cervical cancer

This study investigates whether microsatellite instability (MSI) due to defects of the mismatch repair (MMR) system could be associated with response to cisplatin-based neoadjuvant chemotherapy (NACT) and if cisplatin exposure could select MSI-positive cell clones in cervical cancer. Microsatellite analysis was performed by polymerase chain reactions using six microsatellite markers, while hMLH1 protein expression was investigated by immunohistochemistry. We found that 1 tumor out of 20 (5%) NACT-responding patients and 1 tumor out of 18 (6%) nonresponding patients showed MSI. The analysis of tumor specimens collected after NACT revealed no change in the banding pattern as compared to each corresponding pre-NACT tumor at each locus tested. hMLH1 staining was observed in at least ≥80% of cells in all tumors examined except the two exhibiting MSI. Our data showed that MSI due to defects of the MMR system seems not to play a crucial role in the biology of human cervical cancer cells and that MSI seems not to be related to response to chemotherapy. Moreover, cisplatin exposure did not seem to select for MMR-deficient tumor clones in cervical cancer

Phase II Study of Pegylated Liposomal Doxorubicin in Heavily Pretreated Epithelial Ovarian Cancer Patients

OBJECTIVE

Pegylated liposomal doxorubicin (PLD) has shown promising activity in the treatment of recurrent ovarian cancer but skin toxicity remains the dose-limiting toxicity of the drug. The aim of this study was to investigate whether a different treatment schedule may improve the toxicity profile, especially in terms of dermatological and mucosal toxicity.

METHODS

It is an open-label phase II study in a population of heavily pretreated ovarian cancer patients. PLD was administered at the dose of 35 mg/m2 q21 until disease progression or unacceptable toxicity.

RESULTS

Thirty-seven heavily pretreated (median number of previous chemotherapy regimens 2, range 1-6) ovarian cancer patients were enrolled. All patients received at least two courses of chemotherapy and all were evaluated for response. No one showed complete response, while five partial responses (13.5%), 16 stabilizations of disease (48.6%) and 14 progressions of disease (37.8%) were observed. The median time to response was 12 weeks (range 8-16). The median duration of response was 22.8 weeks (range 4-68), the median duration of stabilization of disease was 17.6 weeks (range 4-28). Palmar plantar erythrodysesthesia (PPE) occurred in 8 patients (21.6%) and was of grade 3 in one patient (2.8%). Grade 1 stomatitis occurred in 3 patients (8.1%). Grade 3-4 neutropenia occurred in only 4 patients (10.8%).

CONCLUSIONS

PLD at the dose of 35 mg/m2 q21 seems to translate into an acceptable skin toxicity profile with a response rate comparable to others obtained with a standard schedule.

Sonographic features of decidualized ovarian endometriosis suspicious for malignancy

The discovery of an ovarian mass during pregnancy is often a difficult issue because of the risk related to surgical intervention during pregnancy. Moreover, ultrasound examination is often unable to provide a definitive diagnosis. A case of decidualized ovarian endometriosis is presented to highlight the challenges in this diagnosis. We report the transvaginal ultrasound findings, including color Doppler examination, magnetic resonance characteristics and tumor marker longitudinal evaluation during the first trimester of pregnancy, as well as the final histological characteristics of the lesion. Decidualization is a rare occurrence in ovarian endometriosis and must be differentiated from malignant transformation.

Color Doppler velocimetry and three-dimensional color power angiography of cervical carcinoma

OBJECTIVES

To investigate the blood flow within invasive cervical carcinoma by transvaginal two-dimensional (2D) color spectral Doppler and three-dimensional (3D) color power angiography and to correlate these parameters with the clinicopathological characteristics.

METHODS

Seventy-four patients with invasive cervical carcinoma were enrolled for the analysis. Squamous cell carcinoma serum antigen levels (SCC) were obtained for all the patients. Sections of all malignant tissues were analyzed for tumor expression of cyclooxygenase-2 (COX-2). All patients underwent color and spectral Doppler examination and 44 patients had 3D color power angiography. Color spectral Doppler parameters (color score, lowest resistance index (RI), highest peak systolic velocity (PSV)) and 3D color power angiography indices (relative color, average color, flow measure) of FIGO I/II cervical cancers were compared with those obtained in a control group of 24 patients with a normal uterine cervix. Pulsed Doppler parameters and the 3D vascular indices were compared with clinicopathological parameters, SCC serum antigen levels and tumor COX-2 expression.

RESULTS

At color Doppler analysis 72 patients (97%) showed intralesional detectable vessels. Color spectral Doppler and 3D-derived parameters were significantly different in FIGO I/II cervical cancers compared with those in women with a normal cervix. A significantly higher color score (P = 0.0008), lower RI (P = 0.032) and higher PSV (P = 0.004) were associated with a tumor diameter > or =4 cm compared with smaller tumors. The highest PSV was significantly higher in patients with FIGO stage III/IV compared with FIGO stage I/II (P = 0.0069). There was a direct correlation between PSV and SCC (r = +0.44, P = 0.003). The median relative color was significantly higher in patients with a higher color score (P = 0.0006). No statistically significant correlations were found between 3D color power angiography parameters and the clinicopathological characteristics or between the 3D vascular parameters and biological factors.

CONCLUSIONS

Alterations of 3D ultrasound-derived vascular indices were found in patients with cervical cancer compared with those with a normal cervix. Moreover, some vascular indices proved to be associated with tumor size. The assessment of a possible clinical role of 2D and 3D ultrasound-derived vascular indices in cervical cancer deserves further investigation.

Epidermal growth factor-responsive laryngeal squamous cancer cell line Hep2 is more sensitive than unresponsive CO-K3 one to quercetin and tamoxifen apoptotic effects

Epidermal growth factor receptor (EGFR) plays a role in laryngeal squamous cell carcinoma (SCC) development and progression. The flavonoid quercetin (Q) and the antiestrogen tamoxifen (TAM) inhibit proliferation of both primary laryngeal SCC and laryngeal carcinoma cell lines, through still uncharacterized mechanisms. We studied Q and TAM inhibitory effect on epidermal growth factor (EGF)-stimulated Hep2 and CO-K3 laryngeal squamous cell lines. Q and TAM (0.1-1.0 microM) induced more apoptosis in EGF growth-stimulated than in unstimulated Hep2 cells. EGF neither stimulated CO-K3 cell growth nor enhanced Q and TAM-induced apoptosis. Mitogen-activated protein kinase (MAPK) analysis revealed that in Hep2 cells, but not in CO-K3 cells, EGF induced a time-dependent phosphorylation of p42, p44, p38, and p46. In Hep2 cells, but not in CO-K3 cells, Q and TAM produced, upon EGF treatment, a twofold increase of p38 and p46 and an enhancement of p42 and p44 dephosphorylation, suggesting a requirement of EGFR. The enhancing effect was due to a p38 and p46 dephosphorylation delayed kinetics. An antiphosphorylated p38 antibody prevented Q and TAM inhibitory effect on p42 and p44 phosphorylations, suggesting that the EGF-dependent increase in Q and TAM apoptotic effect on Hep2 cells could depend on the p38 inhibition of the survival kinases p42 and p44. In SCC, EGFR overexpression is an early event from dysplasia to neoplasia. We conclude that the capacity of Q and TAM to increase apoptosis in EGFR-activated cells makes these compounds possible chemopreventive drugs in subjects at risk of developing laryngeal cancer.