Efficacy and safety of imatinib mesylate (Gleevec®) and immunohistochemical expression of c-Kit and PDGFR-β in a Gynecologic Oncology Group Phase Il Trial in women with recurrent or persistent carcinosarcomas of the uterus

Trastuzumab Deruxtecan for Human Epidermal Growth Factor Receptor 2-Expressing Advanced or Recurrent Uterine Carcinosarcoma (NCCH1615): The STATICE Trial

PURPOSE

To investigate the efficacy and safety of trastuzumab deruxtecan, an antibody-drug conjugate targeting human epidermal growth factor receptor 2 (HER2) with a topoisomerase I inhibitor payload, in patients with uterine carcinosarcoma (UCS) expressing HER2.

PATIENTS AND METHODS

Patients with recurrent UCS with HER2 immunohistochemistry scores ≥1+ previously treated with chemotherapy were included. Patients were assigned to the HER2-high (immunohistochemistry score ≥2+; n = 22) or low (immunohistochemistry score of 1+; n = 10) groups for primary and exploratory analyses, respectively. Trastuzumab deruxtecan 6.4 or 5.4 mg/kg was administered intravenously once every 3 weeks until unacceptable toxicity or disease progression. Dose modification was based on the updated recommended phase II dose for breast cancer to be 5.4 mg/kg. The primary end point was the objective response rate by central review in the HER2-high group. Secondary end points included the overall response rate (ORR) in the HER2-high group by investigator assessment, ORR in the HER2-low group, progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

The ORR by central review in the HER2-high and HER2-low groups were 54.5% (95% CI, 32.2 to 75.6) and 70.0% (95% CI, 34.8 to 93.3) and those by investigator assessments were 68.2% and 60.0%, respectively. The median PFS and OS in the HER2-high and HER2-low groups were 6.2 and 13.3 months and 6.7 months and not reached, respectively. Grade ≥ 3 adverse events occurred in 20 patients (61%). Grades 1-2 and 3 pneumonitis/interstitial lung disease occurred in eight (24%) and one (3%) patient, respectively.

CONCLUSION

Trastuzumab deruxtecan has efficacy in patients with UCS, regardless of HER2 status. The safety profile was generally consistent with that previously reported. Toxicities were manageable with appropriate monitoring and treatment.

Endometrial carcinosarcoma

Endometrial carcinosarcoma is a rare and aggressive high-grade endometrial carcinoma with secondary sarcomatous trans-differentiation (conversion theory). The clinical presentation and diagnostic work-up roughly align with those of the more common endometrioid counterpart, although endometrial carcinosarcoma is more frequently diagnosed at an advanced stage. Endometrial carcinosarcoma is not a single entity but encompasses different histological subtypes, depending on the type of carcinomatous and sarcomatous elements. The majority of endometrial carcinosarcomas are characterized by p53 abnormalities. The proportion of POLE and microsatellite instablity-high (MSI-H) is directly related to the epithelial component, being approximately 25% and 3% in endometrioid and non-endometrioid components.The management of non-metastatic disease is based on a multimodal approach with optimal surgery followed by (concomitant or sequential) chemotherapy and radiotherapy, even for early stages. Palliative chemotherapy is recommended in the metastatic or recurrent setting, with carboplatin/paclitaxel doublet being the first-line regimen. Although the introduction of immunotherapy plus/minus a tyrosine kinase inhibitor shifted the paradigm of treatment of patients with recurrent endometrial cancer, patients with endometrial carcinosarcoma were excluded from most studies evaluating single-agent immunotherapy or the combination. However, the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) approved the use of pembrolizumab and lenvatinib in endometrial cancer (all histotypes) after progression on chemotherapy and single-agent immunotherapy in MSI-H cancers. In the era of precision medicine, emerging knowledge on molecular endometrial carcinosarcoma is opening new promising therapeutic options for more personalized treatment. The present review outlines state-of-the-art knowledge and future directions for patients with endometrial carcinosarcoma.

CNS metastasis secondary to malignant-mixed Müllerian tumor: case report and review of therapeutics

This paper reviews CNS involvement secondary to malignant-mixed Müllerian tumor or uterine carcinosarcoma, a rare aggressive biphasic Müllerian tumor. We report a cerebellar metastasis with epithelial and mesenchymal components, demonstrating heterologous rhabdomyogenic and chondroblastic differentiation. The patient had undergone total abdominal hysterectomy and bilateral salpingo-oophorectomy for palliation of symptomatic chemotherapy-resistant node-positive disease. CNS involvement is rare, and prognostically poor, and suggestively poorer in predominantly sarcomatous metastases. Multimodal therapy is indicated; in solitary metastases, surgical resection or stereotactic radiosurgery is included, followed by whole brain radiotherapy. In unresectable brain metastases, stereotactic radiosurgery and whole brain radiotherapy warrant consideration in up to 2-3 metastases. In multiple metastases, palliative steroid therapy or cranial irradiation may be considered. Combination or platinum-based chemotherapy (i.e., ifosfamide-paclitaxel or carboplatin-paclitaxel) is indicated in all stages, with a role in both disease cure and control-directed management. Targeted therapeutics have thus far not demonstrated significant clinical efficacy.

A phase II evaluation of ixabepilone in the treatment of recurrent/persistent carcinosarcoma of the uterus, an NRG Oncology/Gynecologic Oncology Group study

BACKGROUND

The primary objectives were to determine the objective response rate (ORR) and safety profile of ixabepilone in women with recurrent or persistent uterine carcinosarcoma (UCS). Secondary objectives included progression-free survival (PFS) and overall survival (OS). Exploratory translational objectives included characterization of class III beta tubulin expression and its association with response, PFS, and OS.

METHODS

Patients had measurable disease; up to two prior chemotherapeutic regimens were allowed, but must have included a taxane. Women received ixabepilone 40mg/m² as a 3hour IV infusion on day 1 of a 21daycycle. Treatment was continued until disease progression or unacceptable toxicity occurred.

RESULTS

Forty-two women were enrolled, with 34 eligible and evaluable. Median age was 68years. ECOG performance status was 0 in 56% of women, 38% had received radiation, and 15% had received 2 lines of chemotherapy. Overall ORR was 11.8% (4/34, 90% CI 4.2-25.1%); all were partial responses. Stable disease for at least 8weeks was achieved in 8 patients (23.5%). Median PFS and OS were 1.7mo and 7.7mo, respectively, with a median follow-up of 37mo. Six month PFS was 20.6%. Major grade≥3 toxicities were neutropenia (47%), fatigue (15%), dehydration (15%), hypertension (15%), and hyponatremia (15%); grade 2 peripheral neuropathy was reported in 18%. In this small sample size, class III beta tubulin expression in the primary tumor was not associated with the response to ixabepilone, PFS, or OS.

CONCLUSION

In this cohort of women, single agent ixabepilone showed modest but insufficient clinical activity.

Review of Recommended Treatment of Uterine Carcinosarcoma

Surgery is the primary treatment for uterine carcinosarcoma (UCS). Lymphadenectomy should be performed for staging purposes in tumors apparently confined to the uterus. Most studies found that lymphadenectomy is of therapeutic value. The therapeutic value of cytoreduction to no residual macroscopic disease in advanced UCS is based mostly on small retrospective uncontrolled studies. Postoperative adjuvant therapy should be considered for all stages of UCS. Adjuvant pelvic radiotherapy may reduce locoregional recurrences. However, this does not translate into improved overall survival since most recurrences are distant outside the irradiated field, and the survival rates remain poor, the 5-year overall survival being about 50%. Several adjuvant platin-based combination chemotherapy schedules such as cisplatin/ifosfamide, ifosfamide/paclitaxel, and paclitaxel/carboplatin have been found to be an effective mode of adjuvant treatment. Multimodal therapy (i.e., adjuvant chemotherapy plus radiotherapy) has also been shown to be effective. Most studies dealing with adjuvant treatment are retrospective and prospective randomized controlled trials (i.e., phase III studies) comparing that between the various adjuvant chemotherapy schedules and between them and multimodal treatment are lacking. Quality of life with the various treatment modalities needs also to be assessed. An effective targeted therapy has so far not been found. In spite of the multiple studies with regard to the treatment of UCS published during the last 15 years, the optimal management of UCS is still not established.

Clinical Characteristics, Surgical Management and Adjuvant Therapy of Patients with Uterine Carcinosarcoma: A Retrospective Case Series

Purpose: To review a single-center experience over a 27-year period of managing uterine carcinosarcoma (UCS), focusing on surgical practice, adjuvant therapy and clinical outcome. Material and Methods: This was a retrospective study of women with histologically proven UCS treated at the Department of Obstetrics and Gynecology, University of Tübingen, Germany, between 1983 and 2010. Inpatient and outpatient records were reviewed; follow-up and survival data were ascertained. Results: The study population comprised 18 patients with UCS. Primary surgical treatment consisted of total abdominal hysterectomy in 12 patients (67 %) and laparoscopic total hysterectomy in 4 patients (22 %). Bilateral salpingo-oophorectomy was performed in 94 % of patients (17/18). Lymph nodes were evaluated in 15 patients (83 %). Positive pelvic lymph nodes were present in 2 patients (11 %). A total of 17 patients (94 %) received adjuvant therapy. Disease recurred in 7 (39 %) patients of our study group, with no recurrence noted in the 4 patients who underwent laparoscopic surgical staging. Median disease-free survival (DFS) was 48.7 months (95 % CI: 0.0-157.3) and median overall survival (OS) was 49.9 months (95 % CI: 0.0-108.2). The 5-year survival rate was 40 %. Conclusion: UCS is a rare and aggressive uterine neoplasm with high recurrence rates and metastatic potential. Surgical staging consisting of total hysterectomy with bilateral salpingo-oophorectomy and systematic lymphadenectomy is the most important treatment for patients with UCS. Adjuvant radiation therapy appears to decrease pelvic recurrence, but there is a high incidence of distant recurrence, indicating the need for additional systemic treatment.

Gynecologic Cancer InterGroup (GCIG) consensus review for uterine and ovarian carcinosarcoma

Carcinosarcomas (also known as malignant mixed müllerian tumors) are rare and highly aggressive epithelial malignancies that contain both malignant sarcomatous and carcinomatous elements. Uterine carcinosarcomas (UCs) are uncommon with approximately more than 35% presenting with extra uterine disease at diagnosis. Up to 90% ovarian carcinosarcomas (OCs) will have disease that has spread beyond the ovary. Prognosis for localized stage disease is poor with a high risk of recurrences, both local and distant, occurring within 1 year. The survival of women with advanced UC or OC is worse than survival of endometrioid or high-grade serous histologies. No improvement in survival rates has been observed in the past few decades with an overall median survival of less than 2 years. Currently, there is no clear evidence to establish consensus guidelines for therapeutic management of carcinosarcomas. Until recently, gynecological carcinosarcomas were considered as a subtype of sarcoma and treated as such. However, carcinosarcomas are now known to be metaplastic carcinomas and so should be treated as endometrial or ovarian high-risk carcinomas, despite the lack of specific data. For UCs, a comprehensive approach to management is recommended with complete surgical staging followed by systemic chemotherapy in patients with both early and advanced stage disease. Active agents include paraplatin, cisplatin, ifosfamide, and paclitaxel. The combination of carboplatin-paclitaxel is the most commonly used regimen in the adjuvant and advanced setting. Adjuvant radiotherapy (external beam irradiation and/or vaginal brachytherapy) has not shown any overall survival benefit but has been reported to decrease local recurrences. For OCs and for other ovarian epithelial cancer, the mainstay of treatment remains cytoreductive surgical effort followed, even in early stage, by platinum-based chemotherapy, usually carboplatin-paclitaxel.

Uterine carcinosarcoma: A review of the literature

OBJECTIVE

Uterine carcinosarcomas (UCSs) are aggressive tumors previously considered to be sarcomas, but now recognized as malignancies composed of metaplastic transformation of epithelial elements. Much of the management for UCS has been extrapolated from studies of endometrial carcinomas and sarcomas. This article critically reviews the literature pertinent to the pathology, pathogenesis, diagnosis and management of women with UCS.

METHODS

MEDLINE was searched for English language literature on UCS with a focus on the past 20years. Given the rarity of this tumor, studies were not limited by design or number of reported patients.

RESULTS

UCS is biologically a de-differentiated endometrial carcinoma with its own pathogenesis and molecular profile. It commonly presents with extrauterine disease which can be identified by comprehensive surgical staging. Most UCS patients are candidates for adjuvant chemotherapy. The role of radiation is less clear. Combination therapy, while commonly used, has not been studied in depth. The high recurrence rate and poor overall survival for UCS suggest an ongoing need for clinical trials for UCS specifically.

CONCLUSIONS

UCS represents a distinct subtype of uterine malignancy, and should be studied as such via focused clinical trials.

Establishment of primary xenograft model from newly characterized patient extrauterine carcinosarcoma

BACKGROUND AND OBJECTIVE

The aim of this study was to characterize primary cells from extrauterine carcinosarcoma (CS) and to establish a primary CS xenograft mouse model.

METHODS

Primary cells were isolated from a patient with CS and cultured in vitro. Primary CS cells were verified for their ability to consecutively generate tumorigenesis in NOD/SCID mice. The properties of xenograft tumor and explants cells were investigated by immunohistochemistry, cytogenetic, and FACS analysis. Anticancer drug susceptibility of primary CS was analyzed using CCK-8.

RESULTS

Primary CS cells greater than 27 passages in vitro showed an ability of a series of xenograft tumorigenesis in vivo having the same marker expression and cytogenetic character as that of original tumor. In addition, explants of xenograft tumors retained their original characteristics in the in vitro culture system. Finally, the analysis of the susceptibility to anticancer drug revealed that primary CS cells were susceptible to both doxorubicin and nilotinib, which are tyrosine kinase inhibitors.

CONCLUSIONS

The primary CS cells and the primary CS xenograft tumorigenesis introduce a new therapeutic model for targeting cancer and also explore a deeper understanding of generation of the tumor itself.

A phase II evaluation of pazopanib in the treatment of recurrent or persistent carcinosarcoma of the uterus: a gynecologic oncology group study

OBJECTIVE

Carcinosarcomas of the female genital tract, also called malignant mixed müllerian tumors, are aggressive biphasic tumors. Second-line treatment options in the recurrent/persistent setting have yielded marginal responses. Given the potential role of angiogenesis in the gynecological carcinomas, pazopanib, a VEGFR inhibitor, was investigated in the management of patients with recurrent carcinosarcoma of the uterus.

METHODS

Eligible patients had histologically confirmed carcinosarcoma of the uterus, a maximum of two prior lines of therapy, adequate renal, hepatic and hematologic function and a performance status of 0-2. Pazopanib was administered orally at 800mg. Two dose reductions were allowed. The primary objective was to ascertain the activity of pazopanib as measured by the proportion of patients who survive progression-free for at least six months and the proportion of patients that have objective tumor responses. Secondary objectives included the frequency and severity of adverse events as assessed by CTCAE v4.0.

RESULTS

Of the 22 enrolled patients, 19 were eligible and evaluable for toxicity and survival. No patients had a partial or complete response (90% confidence interval [CI]: 0%, 14.6%). Three patients (15.8%) had PFS ≥6months (90% CI: 4.4%, 35.9%). The median PFS was 2.0months (first and third quartiles were 1.6 and 4.0months, respectively). The median overall survival was 8.7months (first and third quartiles were 2.6 and 14.0months, respectively).

CONCLUSION

Pazopanib demonstrated minimal activity as a second or third line treatment for advanced uterine carcinosarcoma. Potential clinical trial participation should be discussed with the patients.

Imatinib sensitizes endometrial cancer cells to cisplatin by targeting CD117-positive growth-competent cells

The use of molecular target therapy has not been established for endometrial cancer. The present study investigated the potential therapeutic strategy of targeting CD117-positive cancer cells as a novel molecular target therapy. FACS-sorted CD117(+) cells isolated from endometrial cancer cell lines (Ishikawa or MFE280 cells) exhibited higher proliferative capacity in vitro and colony forming activity on soft agar, and decreased sensitivity to cisplatin, compared to CD117(-) cells. Immunohistochemical analyses with surgical specimens of endometrial cancers showed that high CD117 expression was tightly linked to advanced FIGO stages, myometrial invasion and histological grade, and was significantly associated with poor overall survival and relapse-free survival (Kaplan-Meier analysis; p<0.001, log-rank test). The Cox-regression hazard model identified high CD117 expression to be an independent prognostic factor for survival (p<0.05). In vitro assay confirmed that stem cell factor (SCF), a ligand of CD117, was produced specifically in CD117(+) cells of endometrial cancer, and the colony-forming activity were abrogated by adding anti-SCF antibody, indicating an SCF-dependent growth property. Imatinib was confirmed to selectively target CD117(+) cells in vitro, and synergistically enhanced the anti-tumor effect of low dose cisplatin in vivo, which showed only modest effects when used as a single use. These findings suggest that CD117 can be a marker of aggressive behavior of cells as well as an independent prognostic marker in endometrial cancer. Targeting of the SCF/CD117 axis by imatinib sensitized endometrial cancer cells to cisplatin, proposing a novel therapeutic strategy for this tumor type.

Cancerous ovarian stem cells: obscure targets for therapy but relevant to chemoresistance

Chemotherapy with platinum and taxanes is the first line of treatment for all epithelial ovarian cancer (EOC) patients after debulking surgery. Even though the treatment is initially effective in 80% of patients, recurrent cancer is inevitable in the vast majority of cases. Emerging evidence suggests that some tumor cells can survive chemotherapy by activating the self-renewal pathways resulting in tumor progression and clinical recurrence. These defined population of cells commonly termed as "cancer stem cells" (CSC) may generate the bulk of the tumor by using differentiating pathways. These cells have been shown to be resistant to chemotherapy and, to have enhanced tumor initiating abilities, suggesting CSCs as potential targets for treatment. Recent studies have introduced a new paradigm in ovarian carcinogenesis which proposes in situ carcinoma at the fimbrial end of the fallopian tube to generate high-grade serous ovarian carcinomas, in contrast to ovarian cortical inclusion cysts (CIC) which produce borderline and low grade serous, mucinous, endometrioid, and clear cell carcinomas. This review summarizes recent advances in our understanding of the cellular origin of EOC and the molecular mechanisms defining the basis of CSC in EOC progression and chemoresistance. Using a model ovarian cancer cell line, we highlight the role of CSC in response to chemotherapy, and relate how CSCs may impact on chemoresistance and ultimately recurrence. We also propose the molecular targeting of CSCs and suggest ways that may improve the efficacy of current chemotherapeutic regimens needed for the management of this disease.

Endometrial stromal tumors: immunohistochemical and molecular analysis of potential targets of tyrosine kinase inhibitors

BACKGROUND

The systemic treatment of malignant endometrial stromal tumors (EST) is not well established. A few reports describe objective responses to imatinib, which suggest a novel therapeutic strategy for these tumors. Due to these facts, we aimed to perform a retrospective analysis of possible molecular targets of tyrosine kinase inhibitors (TKI) in EST: KIT, PDGFRA and EGFR.

METHODS

52 endometrial stromal sarcomas and 13 undifferentiated endometrial sarcomas were examined and reviewed. Mutational analysis were performed for exons 9, 11, 13, and 17 of the KIT gene, exons 12 and 18 of the PDGFRA gene and exons 18, 19, 20 and 21 of the EGFR gene. The incidence and distribution of the KIT, PDGFRA, and EGFR expression were examined by immunohistochemistry, and EGFR amplification was assessed by fluorescence in situ hybridization.

RESULTS

No mutations in KIT, PDGFRA and EGFR genes were detected. Overexpression of KIT, PDGFRA, EGFR, was detected in 2 (3%), 23 (35.4%), 7 (10.8%) cases respectively, whereas amplification of EGFR gene was not found.

CONCLUSIONS

Absence of significant expression, amplification and activating mutations on these tyrosine kinase receptors suggest that it is unlikely that EST can benefit from therapies such as TKI on the systemic setting.

Wilms' tumor 1 protein and estrogen receptor beta expression are associated with poor outcomes in uterine carcinosarcoma

BACKGROUND

Uterine carcinosarcoma (CS) is an aggressive malignancy. Increased expression of Wilms' tumor 1 (WT1) protein and estrogen receptor beta (ER-β) protein is associated with worse outcomes in gynecologic cancers; therefore, we sought to assess this association in CS patients.

METHODS

A retrospective analysis was conducted for women diagnosed with uterine CS from departmental databases. WT1/ER-β expression was determined by immunohistochemical staining and scoring of specimens. Univariate and multivariate models were used to correlate progression-free survival (PFS) and overall survival (OS) with WT1/ER-β expression and clinicopathologic factors.

RESULTS

Ninety four patients had mean follow-up of 27 months. Postoperative treatments included chemotherapy for 52 (55 %) subjects and radiotherapy for 25 (27 %). Sixty-four (68 %) and 74 (79 %) tumor samples expressed WT1 and ER-β by immunohistochemistry, respectively. On univariate analysis, stage (p = .02) and lower uterine segment invasion (LUSI) (p = .001) were associated with decreased PFS. Only stage (p = .003) was linked to OS. In the total sample, increased WT1 expression was marginally associated with impaired PFS (p = .07) and OS (p = .09) but ER-β expression was not associated with PFS (p = .89) or OS (p = .30). WT1 and ER-β concurrent expression was associated with impaired OS (p = .02) and PFS (p = .02). On multivariate analysis, LUSI was a significant prognostic factor for PFS [hazard ratio (HR) 2.21, 95 % confidence interval (CI) = 1.12-4.32, p = .03] and stage for OS (HR 3.20, 95 % CI = 1.23-8.35, p = .02). Increased WT1/ER-β expression was associated with impaired OS (HR 1.31, 95 % CI = 1.02-1.69, p = .04).

CONCLUSIONS

Concurrent increased WT1 and ER-β expression impairs prognosis for women with uterine CS. Further research is warranted to define how relevant pathways interact and whether targeting these pathways improves OS.

A phase II study single agent of aflibercept (VEGF Trap) in patients with recurrent or metastatic gynecologic carcinosarcomas and uterine leiomyosarcoma. A trial of the Princess Margaret Hospital, Chicago and California Cancer Phase II Consortia

OBJECTIVE

The aim of this multi-institutional non randomized phase II trial was to determine the efficacy and safety of single agent aflibercept (VEGF Trap), a recombinant fusion protein that blocks multiple vascular endothelial growth factor isoforms, in women with gynecologic soft tissue sarcoma.

METHODS

Patients were enrolled in two cohorts each with Simon two stage designs: uterine leiomyosarcoma and carcinosarcoma of endometrial, ovarian or fallopian tube origin. Eligibility criteria included ≤2 prior lines of chemotherapy for metastatic disease and ECOG performance status of ≤2. Aflibercept 4mg/kg was administered intravenously on day 1 of a 14 day cycle. Primary endpoints were objective response and disease stabilization (Progression Free Survival (PFS) at 6 months).

RESULTS

41 patients with uterine leiomyosarcoma and 22 patients with carcinosarcoma (19 uterine, 3 ovarian) were enrolled on study. In the leiomyosarcoma cohort, eleven (27%) patients had stable disease (SD), 4 with SD lasting at least 24 weeks. The 6 month PFS was 17%, with median time to progression (TTP) of 1.8 (95% CI:1.6-2.1) months. In the carcinosarcoma cohort, two (9%) patients had SD, one lasting >24 weeks, median TTP was 1.6 months (95%CI: 1.1-1.7) No partial responses were observed in patients from either cohort. Grade 3 or more aflibercept related toxicity was uncommon and included hypertension, fatigue, headache and abdominal pain.

CONCLUSIONS

Single agent aflibercept has modest activity in patients with uterine leiomyosarcoma and minimal activity in women with carcinosarcoma.

Uterine carcinosarcomas (malignant mixed müllerian tumours): a review with special emphasis on the controversies in management

Uterine carcinosarcomas (MMMT-malignant mixed Müllerian tumours) are highly aggressive, rare, biphasic tumours composed of epithelial and mesenchymal elements believed to arise from a monoclonal origin. While hysterectomy with bilateral salpingo-oophorectomy remains the mainstay treatment, high rates of recurrence and metastases suggest a need for lymphadenectomy and postoperative adjuvant treatment. There are no established consensus guidelines for therapeutic patient management. Though well recognized that it improves locoregional control, the role of radiation in improving overall survival outcomes remains undecided. Although various combinations of chemotherapy have been explored, an optimal therapeutic modality is yet to be determined. As overall survival rates have not improved in thirty years, it is suggested that targeted chemotherapy and/or a multimodality approach may yield better outcomes. This paper provides a summary of the aetiopathogenesis of carcinosarcomas (MMMT) limited to the uterus with special emphasis on the controversies in the management of these patients.

The good oncogene: When bad genes identify good outcome in cancer

Some cancer patients live many decades after diagnosis while others are not so fortunate. Understanding why this occurs is a fundamental issue in cancer research. We hypothesize that among the factors controlling favorable outcome are a class of genes that we describe as "good oncogenes". These genes have a paradoxical function in cancer in that they are prognostic markers for favorable survival but have strong transforming and tumour-promoting properties. As such, good oncogenes both promote neoplasia and constrain it. We propose that good oncogenes enhance outcome probability by allowing early tumor detection, sensitizing cancer cells to senescence or by attenuating metastatic progression and tumour self-renewal. We believe that understanding the signaling pathways regulated by good oncogenes provides mechanistic insight into the biochemical basis for long-term survival in cancer.