A mitogen-activated protein kinase kinase inhibitor induced compound skin toxicity with oedema in metastatic malignant melanoma.

We report three cases of skin toxicity associated with oral mitogen-activated protein kinase kinase (MEK) inhibitor treatment for metastatic malignant melanoma (MM). All three patients developed oedema, and a single patient experienced eyelash trichomegaly. This is the first known report of eyelash trichomegaly secondary to MEK inhibitor use. We also discuss possible mechanisms for MEK inhibitor-associated oedema development. This series supports the role of the dermatologist in the screening and management of patients in the rapidly developing oncology setting, as new targeted agents can give rise to marked skin toxicity.

Final results from the large sunitinib global expanded-access trial in metastatic renal cell carcinoma.

BACKGROUND: We report final results with extended follow-up from a global, expanded-access trial that pre-regulatory approval provided sunitinib to metastatic renal cell carcinoma (mRCC) patients, ineligible for registration-directed trials. METHODS: Patients ⩾18 years received oral sunitinib 50 mg per day on a 4-weeks-on-2-weeks-off schedule. Safety was assessed regularly. Tumour measurements were scheduled per local practice. RESULTS: A total of 4543 patients received sunitinib. Median treatment duration and follow-up were 7.5 and 13.6 months. Objective response rate was 16% (95% confidence interval (CI): 15-17). Median progression-free survival (PFS) and overall survival (OS) were 9.4 months (95% CI: 8.8-10.0) and 18.7 months (95% CI: 17.5-19.5). Median PFS in subgroups of interest: aged ⩾65 years (33%), 10.1 months; Eastern Cooperative Oncology Group performance status ⩾2 (14%), 3.5 months; non-clear cell histology (12%), 6.0 months; and brain metastases (7%), 5.3 months. OS was strongly associated with the International Metastatic Renal-Cell Carcinoma Database Consortium prognostic model (n=4065). The most common grade 3/4 treatment-related adverse events were thrombocytopenia (10%), fatigue (9%), and asthenia, neutropenia, and hand-foot syndrome (each 7%). CONCLUSION: Final analysis of the sunitinib expanded-access trial provided a good opportunity to evaluate the long-term side effects of a tyrosine kinase inhibitor used worldwide in mRCC. Efficacy and safety findings were consistent with previous results.

Efficacy and safety of sunitinib in elderly patients with metastatic renal cell carcinoma.

BACKGROUND: We retrospectively analyzed sunitinib outcome as a function of age in metastatic renal cell carcinoma (mRCC) patients. METHODS: Data were pooled from 1059 patients in six trials. Kaplan-Meier estimates of progression-free survival (PFS) and overall survival (OS) were compared by log-rank test between patients aged <70 (n=857; 81%) and ≥70 (n=202; 19%) years. RESULTS: In first-line patients, median PFS was comparable in younger and older patients, 9.9 vs 11.0 months, respectively (HR, 0.89; 95% CI: 0.73-1.09; P=0.2629), as was median OS, 23.6 vs 25.6 months (HR, 0.93; 95% CI: 0.74-1.18; P=0.5442). Similarly, in cytokine-refractory patients, median PFS was 8.1 vs 8.4 months (HR, 0.79; 95% CI: 0.49-1.28; P=0.3350), while median OS was 20.2 vs 15.8 months (HR, 1.14; 95% CI: 0.73-1.79; P=0.5657). Some treatment-emergent adverse events were significantly less common in younger vs older patients, including fatigue (60% vs 69%), cough (20% vs 29%), peripheral edema (17% vs 27%), anemia (18% vs 25%), decreased appetite (13% vs 29%), and thrombocytopenia (16% vs 25%; all P<0.05). Hand-foot syndrome was more common in younger patients (32% vs 24%). CONCLUSIONS: Advanced age should not be a deterrent to sunitinib therapy and elderly patients may achieve additional clinical benefit.

A randomised, phase II trial of the DNA-hypomethylating agent 5-aza-2'-deoxycytidine (decitabine) in combination with carboplatin vs carboplatin alone in patients with recurrent, partially platinum-sensitive ovarian cancer.

BACKGROUND: Our previous laboratory and clinical data suggested that one mechanism underlying the development of platinum resistance in ovarian cancer is the acquisition of DNA methylation. We therefore tested the hypothesis that the DNA hypomethylating agent 5-aza-2'-deoxycytodine (decitabine) can reverse resistance to carboplatin in women with relapsed ovarian cancer. METHODS: Patients progressing 6-12 months after previous platinum therapy were randomised to decitabine on day 1 and carboplatin (AUC 6) on day 8, every 28 days or carboplatin alone. The primary objective was response rate in patients with methylated hMLH1 tumour DNA in plasma. RESULTS: After a pre-defined interim analysis, the study closed due to lack of efficacy and poor treatment deliverability in 15 patients treated with the combination. Responses by GCIG criteria were 9 out of 14 vs 3 out of 15 and by RECIST were 6 out of 13 vs 1 out of 12 for carboplatin and carboplatin/decitabine, respectively. Grade 3/4 neutropenia was more common with the combination (60% vs 15.4%) as was G2/3 carboplatin hypersensitivity (47% vs 21%). CONCLUSIONS: With this schedule, the addition of decitabine appears to reduce rather than increase the efficacy of carboplatin in partially platinum-sensitive ovarian cancer and is difficult to deliver. Patient-selection strategies, different schedules and other demethylating agents should be considered in future combination studies.

A study of the decision outcomes and financial costs of multidisciplinary team meetings (MDMs) in oncology.

BACKGROUND: The benefits of multidisciplinary working in oncology are now accepted as the norm and widely accepted as being pivotal to the delivery of optimal cancer care. Central to this are the multidisciplinary meetings (MDMs) and we have evaluated decision outcomes and financial costs of these. METHODS: We reviewed the electronic patient records of 551 newly referred patients, discussed at 14 tumour site-specific MDMs for adult solid tumours and lymphoma (paediatric oncology and acute leukaemia were excluded) over a 1-month period, a total of 52 MDMs were studied. In addition, the records of a further 81 patients from 10 different MDMs were reviewed where the treating consultant had clearly recorded their opinion of how the patient should be managed and this was compared with the final MDM's consensus view. We also costed the MDMs utilising two different methodologies. RESULTS: The mean age of the 551 patients in the study was 62 years. In all, 536 (97.3%) patients were treatment naive before MDM discussion and 15 (2.7%) had prior treatment. Median time to treatment after the MDM was 16 days. In 535 (97.1%) cases, the MDM discussions were clearly documented, 16 (2.9%) were not clearly documented. In total, 319 (57.9%) patients were discussed once, and 232 (42.1%) were re-discussed (one to six occasions). In 62 (12.7%) patients, there were delays in MDM discussion, 30 (48.4%) were related to radiology, 26 (41.9%) to histopathology and 6 (9.7%) a combination of both. Adherence to the MDM management plan decision occurred 503 times (91.3%) with 48 (8.7%) deviations. In the smaller cohort of 81 patients, the consultant management plan and MDM consensus was compatible 71 (87.6%) times. On four occasions, there were major alterations in management while six were minor. The cost per month of our MDMs ranged from £2192 to £10 050 (median £5136) with total cost of £80 850 per month and the cost per new patient discussed was £415. CONCLUSION: Adherence to MDM decisions by health-care professionals occurs in the majority of patients. MDMs are costly, which may have relevance in the currently challenged health-care financial environment. There is a need to improve MDM efficiency without losing the considerable benefits associated with regular MDMs.

Prognostic factors for survival in 1059 patients treated with sunitinib for metastatic renal cell carcinoma.

BACKGROUND: Prognostic factors for progression-free survival (PFS), overall survival (OS), and long-term OS (≥30 months) were investigated in sunitinib-treated patients with metastatic renal cell carcinoma (RCC). METHODS: Data were pooled from 1059 patients in six trials. Baseline variables, including ethnicity, were analysed for prognostic significance by Cox proportional-hazards model. RESULTS: Median PFS and OS were 9.7 and 23.4 months, respectively. Multivariate analysis of PFS and OS identified independent predictors, including ethnic origin, Eastern Cooperative Oncology Group performance status, time from diagnosis to treatment, prior cytokine use, haemoglobin, lactate dehydrogenase, corrected calcium, neutrophils, platelets, and bone metastases (OS only). Characteristics of long-term survivors (n=215, 20%) differed from those of non-long-term survivors; independent predictors of long-term OS included ethnic origin, bone metastases, and corrected calcium. There were no differences in PFS (10.5 vs 7.2 months; P=0.1006) or OS (23.8 vs 21.4 months; P=0.2135) in white vs Asian patients; however, there were significant differences in PFS (10.5 vs 5.7 months; P<0.001) and OS (23.8 vs 17.4 months; P=0.0319) in white vs non-white, non-Asian patients. CONCLUSION: These analyses identified risk factors to survival with sunitinib, including potential ethnic-based differences, and validated risk factors previously reported in advanced RCC.

Carboplatin dosage: prospective evaluation of a simple formula based on renal function.

A dosage formula has been derived from a retrospective analysis of carboplatin pharmacokinetics in 18 patients with pretreatment glomerular filtration rates (GFR) in the range of 33 to 136 mL/min. Carboplatin plasma clearance was linearly related to GFR (r = 0.85, P less than .00001) and rearrangements of the equation describing the correlation gave the dosage formula dose (mg) = target area under the free carboplatin plasma concentration versus time curve (AUC) x (1.2 x GFR + 20). In a prospective clinical and pharmacokinetic study the formula was used to determine the dose required to treat 31 patients (GFR range, 33 to 135 mL/min) with 40 courses of carboplatin. The target AUC was escalated from 3 to 8 mg carboplatin/mL/min. Over this AUC range the formula accurately predicted the observed AUC (observed/predicted ratio 1.24 +/- 0.11, r = 0.886) and using these additional data, the formula was refined. Dose (mg) = target AUC x (GFR + 25) is now the recommended formula. AUC values of 4 to 6 and 6 to 8 mg/mL. min gave rise to manageable hematological toxicity in previously treated and untreated patients, respectively, and hence target AUC values of 5 and 7 mg/mL min are recommended for single-agent carboplatin in these patient groups. Pharmacokinetic modeling demonstrated that the formula was reasonably accurate regardless of whether a one- or two-compartment model most accurately described carboplatin pharmacokinetics, assuming that body size did not influence nonrenal clearance. The validity of this assumption was demonstrated in 13 patients where no correlation between surface area and nonrenal clearance was found (r = .31, P = .30). Therefore, the formula provides a simple and consistent method of determining carboplatin dose in adults. Since the measure of carboplatin exposure in the formula is AUC, and not toxicity, it will not be influenced by previous or concurrent myelosuppressive therapy or supportive measures. The formula is therefore applicable to combination and high-dose studies as well as conventional single-agent therapy, although the target AUC for carboplatin will need to be redefined for combination chemotherapy.

Cutaneous adverse events associated with vemurafenib in patients with metastatic melanoma: practical advice on diagnosis, prevention and management of the main treatment-related skin toxicities.

Until recently, no effective treatment was available for patients with metastatic malignant melanoma, and median overall survival was little more than 6 months with the current standard of care, dacarbazine. In 2012, the first specific BRAF mutation inhibitor, vemurafenib, was licensed for the monotherapy of adults with BRAF V600 mutation-positive unresectable or metastatic melanoma. Like other targeted therapies, vemurafenib is associated with a predictable pattern of adverse events, including skin toxicities. We review the most common cutaneous adverse events associated with vemurafenib, based on data from clinical trials, and our own experiences of treating patients in trials and clinical practice. Overall, these toxicities are not preventable, but they rarely necessitate permanent treatment discontinuation and are generally manageable with dose modification and supportive care. We provide a treatment algorithm offering guidance on the most appropriate approach to managing the main skin toxicities to help clinicians unfamiliar with this novel agent to become confident in using vemurafenib effectively in the management of patients with metastatic melanoma.

Outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC).

OBJECTIVE: To describe the outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC) so as to define the criteria for patient selection for palliative surgery. METHODS: 90 women with relapsed EOC underwent palliative surgery for bowel obstruction between 1992 and 2008. RESULTS: Median age at time of surgery for bowel obstruction was 57 years (range, 26 to 85 years). All patients had received at least one line of platinum-based chemotherapy. Median time from diagnosis of primary disease to documented bowel obstruction requiring surgery was 19.5 months (range, 29 days-14 years). Median interval from date of completed course of chemotherapy preceding surgery for bowel obstruction was 3.8 months (range, 5 days-14 years). Ascites was present in 38/90(42%). 49/90(54%) underwent emergency surgery for bowel obstruction. The operative mortality and morbidity rates were 18% and 27%, respectively. Successful palliation, defined as adequate oral intake at least 60 days postoperative, was achieved in 59/90(66%). Only the absence of ascites was identified as a predictor for successful palliation (p=0.049). The median overall survival (OS) was 90.5 days (range, <1 day-6 years). Optimal debulking, treatment-free interval (TFI) and elective versus emergency surgery did not predict survival or successful palliation from surgery for bowel obstruction (p>0.05). CONCLUSION: Surgery for bowel obstruction in relapsed EOC is associated with a high morbidity and mortality rate especially in emergency cases when compared to other gynaecological oncological procedures. Palliation can be achieved in almost two thirds of cases, is equally likely in elective and emergency cases but is less likely in those with ascites.

Challenges and opportunities for converting renal cell carcinoma into a chronic disease with targeted therapies.

Optimum efficacy is the primary goal for any cancer therapy, and entails controlling tumour growth and prolonging survival as far as possible. The prognosis for patients with metastatic renal cell carcinoma (mRCC) has greatly improved with the introduction of targeted therapies. This review examines the development and efficacy of targeted agents for the management of mRCC, the challenges offered by their rapid emergence, and discusses how mRCC treatment may evolve in the future. Improvements in progression-free survival and overall survival rates, observed with targeted agents, indicate that it may now be possible to change mRCC from a rapidly fatal and largely untreatable condition into a chronic disease. The major challenges to further advances in targeted therapy for mRCC include overcoming drug resistance, identifying the most effective sequence or combination of targeted agents, optimising clinical trial design and managing the cost of treatment.

Sorafenib and dacarbazine as first-line therapy for advanced melanoma: phase I and open-label phase II studies.

METHOD: The safety of oral sorafenib up to a maximum protocol-specified dose combined with dacarbazine in patients with metastatic, histologically confirmed melanoma was investigated in a phase I dose-escalation study and the activity of the combination was explored in an open-label phase II study. RESULTS: In the phase I study, three patients were treated with sorafenib 200 mg twice daily (b.i.d.) plus 1000 mg m(-2) dacarbazine on day 1 of a 21-day cycle and 15 patients had the sorafenib dose escalated to 400 mg b.i.d. without reaching the maximum tolerated dose of the combination. In the phase II study (n=83), the overall response rate was 12% (95% CI: 6, 21): one complete and nine partial, with median response duration of 46.7 weeks. Stable disease was the best response in 37%; median duration was 13.3 weeks. Median overall survival (OS) was 37.0 weeks (95% CI: 33.9, 46.0). CONCLUSION: Oral sorafenib combined with dacarbazine had acceptable toxicity and some antineoplastic activity against metastatic melanoma.

A randomised, phase II study of intetumumab, an anti-αv-integrin mAb, alone and with dacarbazine in stage IV melanoma.

BACKGROUND: α(v) integrins are involved in angiogenesis and melanoma tumourigenesis. Intetumumab (CNTO 95) is a fully human anti-α(v)-integrin monoclonal antibody. METHODS: In a multicentre, randomised, phase II study, stage IV melanoma patients were randomised 1:1:1:1 to 1000 mg m(-2) dacarbazine+placebo (n=32), 1000 mg m(-2) dacarbazine+10 mg kg(-1) intetumumab (n=32), 10 mg kg(-1) intetumumab (n=33), or 5 mg kg(-1) intetumumab (n=32) q3w. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), adverse events, and pharmacokinetics. RESULTS: No statistically significant differences in efficacy were observed between groups. In the dacarbazine+placebo, dacarbazine+intetumumab, 10 mg kg(-1) intetumumab, and 5 mg kg(-1) intetumumab groups, median PFS was 1.8, 2.5, 1.4, and 1.4 months; median OS was 8, 11, 15, and 9.8 months; and ORR of complete+partial response was 10, 3, 6, and 0%. Nonlinear intetumumab pharmacokinetics and potential intetumumab-dacarbazine interactions were observed. Transient, asymptomatic, nonrecurring, grade 1-2, uveitic reactions that resolved spontaneously or with topical steroids were seen in 22-30% of intetumumab-treated patients. Low-grade infusion-reaction symptoms (headache, fatigue, nausea, vomiting, fever, chills) were observed, as expected, in 16-73% of dacarbazine-treated patients. No intetumumab-related myelosuppression, laboratory/electrocardiogram abnormalities, or deaths occurred. CONCLUSION: With its favourable safety profile and a nonsignificant trend towards improved OS, intetumumab merits further investigation in advanced melanoma.

A phase I/II trial of sorafenib and infliximab in advanced renal cell carcinoma.

BACKGROUND: There is clinical evidence to suggest that tumour necrosis factor-α (TNF-α) may be a therapeutic target in renal cell carcinoma (RCC). Multi-targeted kinase inhibitors, such as sorafenib and sunitinib, have become standard of care in advanced RCC. The anti-TNF-α monoclonal antibody infliximab and sorafenib have differing cellular mechanisms of action. We conducted a phase I/II trial to determine the safety and efficacy of infliximab in combination with sorafenib in patients with advanced RCC. METHODS: Eligible patients were systemic treatment-naive or had received previous cytokine therapy only. Sorafenib and infliximab were administered according to standard schedules. The study had two phases: in phase I, the safety and toxicity of the combination of full-dose sorafenib and two dose levels of infliximab were evaluated in three and three patients, respectively, and in phase II, further safety, toxicity and efficacy data were collected in an expanded patient population. RESULTS: Acceptable safety was reported for the first three patients (infliximab 5 mg kg⁻¹) in phase 1. Sorafenib 400 mg twice daily and infliximab 10 mg kg⁻¹ were administered to a total of 13 patients (three in phase 1 and 10 in phase 2). Adverse events included grade 3 hand-foot syndrome (31%), rash (25%), fatigue (19%) and infection (19%). Although manageable, toxicity resulted in 75% of the patients requiring at least one dose reduction and 81% requiring at least one dose delay of sorafenib. Four patients were progression-free at 6 months (PFS6 31%); median PFS and overall survival were 6 and 14 months, respectively. CONCLUSION: Sorafenib and infliximab can be administered in combination, but a significant increase in the numbers of adverse events requiring dose adjustments of sorafenib was observed. There was no evidence of increased efficacy compared with sorafenib alone in advanced RCC. The combination of sorafenib and infliximab does not warrant further evaluation in patients with advanced RCC.

A feasibility study of sequential doublet chemotherapy comprising carboplatin-doxorubicin and carboplatin-paclitaxel for advanced endometrial adenocarcinoma and carcinosarcoma.

BACKGROUND: Platinum compounds, taxanes and anthracyclines provide the major effective drug classes in the treatment of advanced and recurrent endometrial cancer and carcinosarcoma. PATIENTS AND METHODS: A total of 52 women with advanced or recurrent endometrial cancer and carcinosarcoma were treated with four cycles of carboplatin area under the curve (AUC) 5 and doxorubicin (50 mg/m(2)) for four cycles before or after four cycles of carboplatin AUC5 and paclitaxel (175 mg/m(2)) with each cycle administered at 21-day intervals. RESULTS: Thirty-seven patients (71.2%) completed all planned treatment. Excluding six patients who did not complete treatment for non-drug-related causes, 80.4% completed all planned treatment. Three hundred and seventy-one treatment cycles were administered and 303 (81.7%) occurred on time. Common Toxicity Criteria grade 3/4 haematological toxic effects, particularly neutropenia and thrombocytopenia, were the predominant cause of treatment delays and dose reductions. A low incidence of grade 3 neurotoxicity and no cardiac toxicity were observed. The overall response rates for patients with evaluable disease were 82.1% and 66.7% for endometrial and carcinosarcoma, respectively. At a median follow-up of 21 months, the median progression-free survival for the endometrial adenocarcinoma and carcinosarcoma cohorts were 15.3 and 12.0 months, respectively. CONCLUSION: This regimen is generally well tolerated with encouraging efficacy.

The role of human endogenous retroviruses in melanoma.

Sequencing of the human genome has established that our DNA harbours many endogenous retrovirus (ERV) sequences, remnants of ancestral exogenous retroviral infections fixed in the germline DNA. In recent years, human ERVs (HERVs) have been implicated in melanomagenesis. Retrovirus-like particles and the expression of HERV mRNA and proteins have been demonstrated in melanoma tissue. In addition, antibodies to HERV proteins have been observed in patients with melanoma. In vitro and mouse models have provided fascinating insights into the potential mechanisms of HERVs in melanomagenesis. This review considers the evidence associating HERVs with melanoma.

Epirubicin, cisplatin and protracted venous infusion 5-Fluorouracil chemotherapy for advanced salivary adenoid cystic carcinoma.

AIMS: Adenoid cystic carcinoma (ACC) is a rare tumour that usually arises in the salivary glands. Initial management is surgery often combined with adjuvant radiotherapy. Chemotherapy is reserved for treatment of symptomatic recurrence. We evaluated the combination of epirubicin, cisplatin and protracted venous infusion 5-fluorouracil (ECF) in the management of ACC. MATERIALS AND METHODS: Patients referred for treatment of advanced, symptomatic ACC were considered. The drugs given were epirubicin 50 mg/m(2) 3-weekly, cisplatin 60 mg/m(2) 3-weekly and protracted venous infusion 5-fluorouracil 200 mg/m(2)/day. RESULTS: Eight patients (median age 46 years) received a median of five cycles of chemotherapy. All patients had had previous surgery, seven had had previous radiotherapy and one had had previous chemotherapy. One patient showed a partial response (duration 34 months) and five showed stable disease (median duration 13.6 months [6.8-15.9+ months]). Median survival was 27 months (3.5-62.3 months). CONCLUSIONS: The activity of ECF in ACC of the head and neck seems to be similar to the combination of cisplatin and 5-fluorouracil and single-agent epirubicin.

Mucinous ovarian cancer.

Mucinous epithelial ovarian cancer (mEOC) accounts for approximately 10% of EOCs. Patients presenting with early-stage disease have an excellent prognosis, however, those with advanced disease have a poor outcome with relative resistance to standard ovarian cancer chemotherapy. Molecular and genetic studies demonstrate differences between mucinous and serous EOC supporting the concept that these tumors develop along separate pathways. Together with the observed differences in clinical behavior and outcome for mEOC, there is a need to develop specific therapeutic strategies for this histologic subtype. The relative rarity of advanced mEOC has resulted in few patients enrolled in major ovarian cancer trials. The results of such trials may not necessarily reflect those specific to mEOC. Separate trials testing alternative chemotherapeutics are required. Metastatic mucinous tumors from other sites such as the gastrointestinal tract may present with ovarian involvement. For all mucinous tumors of the ovary, establishing primary as opposed to metastatic cancers is important. Clinical presentation, tumor markers, histologic, and immunohistochemical features are helpful in distinguishing most cases.

Pre-treatment white blood cell subtypes as prognostic indicators in ovarian cancer.

OBJECTIVE: Inflammatory cells can both suppress and stimulate tumour growth and their influence on clinical outcome in cancer patients has been studied in various cancer types. Here we have investigated their influence on outcome in primary epithelial ovarian cancer. STUDY DESIGN: Serum white blood cell numbers according to subtype were recorded prior to treatment in 136 patients with primary epithelial ovarian cancer. Their correlation with overall survival and disease-free survival was analysed using both univariate and multivariate analysis adjusting for the known prognostic factors (age, stage and debulking status). RESULTS: Multivariate analysis demonstrated that a lower lymphocyte fraction of total white blood cells was significantly associated with mortality (p<0.01). On univariate analysis (p=0.0027, HR=1.15), and multivariate analysis of those patients who were optimally debulked (p=0.036, HR=1.17), a higher monocyte count was significantly associated with recurrence. On multivariate analysis amongst those who were suboptimally debulked, a higher eosinophil count was predictive of both recurrence (p=0.0037, HR=1.77) and mortality (p=0.033, HR=1.73). CONCLUSION: High monocyte counts amongst those who were optimally debulked independently predict adverse outcome in primary epithelial ovarian cancer.

A novel point mutation in P450c17 (CYP17) causing combined 17alpha-hydroxylase/17,20-lyase deficiency.

CONTEXT: Combined 17alpha-hydroxylase/17,20-lyase deficiency is a rare cause of congenital adrenal hyperplasia and hypogonadism. Novel single amino acid changes in P450c17 provide potentially important insights into key structural domains for enzyme function. OBJECTIVE, DESIGN, AND SETTING: We report a novel missense mutation in P450c17 in a 17-yr-old female presenting with a malignant mixed germ cell tumor with yolk sac elements who demonstrated clinical and biochemical features of combined 17alpha-hydroxylase/17,20-lyase deficiency. METHODS: Quantitative urinary steroid analysis was performed by high resolution gas chromatography. All eight coding exons of CYP17 were PCR amplified and sequenced. The position of arginine at codon 96 was modeled using the CYP17 structure 2c17 (www.rcsb.org). The CYP17 genes were subcloned into pcDNA3, expressed in HEK-293 cells, and chromatographed. PATIENT AND RESULTS: 17alpha-Hydroxylase deficiency was confirmed by marked reductions in urinary and serum cortisol, androgens, and estradiol. Mutational analysis revealed a novel homozygous R96Q missense mutation in P450c17, affecting an amino acid in a key substrate-binding region of the enzyme, leading to complete inactivity. CONCLUSION: The description of a second missense mutation at codon 96 (R96W and R96Q) in the substrate-binding region of P450c17 provides strong evidence for the key role of this amino acid in 17alpha-hydroxylase/17,20-lyase function. An association between a malignant germ cell tumor and 17alpha-hydroxylase deficiency has not been reported previously, although the presence of gonadoblastoma in the ovary of a patient with this condition has recently been described.