PIK3CA mutations in plasma circulating tumor DNA predict survival and treatment outcomes in patients with advanced cancers.

BACKGROUND: Oncogenic mutations in PIK3CA are prevalent in diverse cancers and can be targeted with inhibitors of the phosphoinositide-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Analysis of circulating tumor DNA (ctDNA) provides a minimally invasive approach to detect clinically actionable PIK3CA mutations. PATIENTS AND METHODS: We analyzed PIK3CA hotspot mutation frequency by droplet digital PCR (QX 200; BioRad) using 16 ng of unamplified plasma-derived cell-free DNA from 68 patients with advanced solid tumors (breast cancer, n = 41; colorectal cancer, n = 13; other tumor types, n = 14). Results quantified as variant allele frequencies (VAFs) were compared with previous testing of archival tumor tissue and with patient outcomes. RESULTS: Of 68 patients, 58 (85%) had PIK3CA mutations in tumor tissue and 43 (74%) PIK3CA mutations in ctDNA with an overall concordance of 72% (49/68, κ = 0.38). In a subset analysis, which excluded samples from 26 patients known not to have disease progression at the time of sample collection, we found an overall concordance of 91% (38/42; κ = 0.74). PIK3CA-mutated ctDNA VAF of ≤8.5% (5% trimmed mean) showed a longer median survival compared with patients with a higher VAF (15.9 versus 9.4 months; 95% confidence interval 6.7-17.1 months; P = 0.014). Longitudinal analysis of ctDNA in 18 patients with serial plasma collections (range 2-22 time points, median 5) showed that those with a decrease in PIK3CA VAF had a longer time to treatment failure (TTF) compared with patients with an increase or no change (10.7 versus 2.6 months; P = 0.048). CONCLUSIONS: Detection of PIK3CA mutations in ctDNA is concordant with testing of archival tumor tissue. Low quantity of PIK3CA-mutant ctDNA is associated with longer survival and a decrease in PIK3CA-mutant ctDNA on therapy is associated with longer TTF.

Multiplex KRASG12/G13 mutation testing of unamplified cell-free DNA from the plasma of patients with advanced cancers using droplet digital polymerase chain reaction.

Background: Cell-free DNA (cfDNA) from plasma offers easily obtainable material for KRAS mutation analysis. Novel, multiplex, and accurate diagnostic systems using small amounts of DNA are needed to further the use of plasma cfDNA testing in personalized therapy. Patients and methods: Samples of 16 ng of unamplified plasma cfDNA from 121 patients with diverse progressing advanced cancers were tested with a KRASG12/G13 multiplex assay to detect the seven most common mutations in the hotspot of exon 2 using droplet digital polymerase chain reaction (ddPCR). The results were retrospectively compared to mutation analysis of archival primary or metastatic tumor tissue obtained at different points of clinical care. Results: Eighty-eight patients (73%) had KRASG12/G13 mutations in archival tumor specimens collected on average 18.5 months before plasma analysis, and 78 patients (64%) had KRASG12/G13 mutations in plasma cfDNA samples. The two methods had initial overall agreement in 103 (85%) patients (kappa, 0.66; ddPCR sensitivity, 84%; ddPCR specificity, 88%). Of the 18 discordant cases, 12 (67%) were resolved by increasing the amount of cfDNA, using mutation-specific probes, or re-testing the tumor tissue, yielding overall agreement in 115 patients (95%; kappa 0.87; ddPCR sensitivity, 96%; ddPCR specificity, 94%). The presence of ≥ 6.2% of KRASG12/G13 cfDNA in the wild-type background was associated with shorter survival (P = 0.001). Conclusion(s): Multiplex detection of KRASG12/G13 mutations in a small amount of unamplified plasma cfDNA using ddPCR has good sensitivity and specificity and good concordance with conventional clinical mutation testing of archival specimens. A higher percentage of mutant KRASG12/G13 in cfDNA corresponded with shorter survival.

Treatment with methylnaltrexone is associated with increased survival in patients with advanced cancer.

BACKGROUND: Methylnaltrexone (MNTX), a peripherally acting µ-opioid receptor (MOR) antagonist, is FDA-approved for treatment of opioid-induced constipation (OIC). Preclinical data suggest that MOR activation can play a role in cancer progression and can be a target for anticancer therapy. PATIENTS AND METHODS: Pooled data from advanced end-stage cancer patients with OIC, despite laxatives, treated in two randomized (phase III and IV), placebo-controlled trials with MNTX were analyzed for overall survival (OS) in an unplanned post hoc analysis. MNTX or placebo was given subcutaneously during the double-blinded phase, which was followed by the open-label phase, allowing MNTX treatment irrespective of initial randomization. RESULTS: In two randomized, controlled trials, 229 cancer patients were randomized to MNTX (117, 51%) or placebo (112, 49%). Distribution of patients' characteristics and major tumor types did not significantly differ between arms. Treatment with MNTX compared with placebo [76 days, 95% confidence interval (CI) 43-109 versus 56 days, 95% CI 43-69; P = 0.033] and response (laxation) to treatment compared with no response (118 days, 95% CI 59-177 versus 55 days, 95% CI 40-70; P < 0.001) had a longer median OS, despite 56 (50%) of 112 patients ultimately crossing over from placebo to MNTX. Multivariable analysis demonstrated that response to therapy [hazard ratio (HR) 0.47, 95% CI 0.29-0.76; P = 0.002) and albumin ≥3.5 (HR 0.46, 95% CI 0.30-0.69; P < 0.001) were independent prognostic factors for increased OS. Of interest, there was no difference in OS between MNTX and placebo in 134 patients with advanced illness other than cancer treated in these randomized studies (P = 0.88). CONCLUSION: This unplanned post hoc analysis of two randomized trials demonstrates that treatment with MNTX and, even more so, response to MNTX are associated with increased OS, which supports the preclinical hypothesis that MOR can play a role in cancer progression. Targeting MOR with MNTX warrants further investigation in cancer therapy. CLINICAL TRIALS NUMBER: NCT00401362, NCT00672477.

Pre-treatment levels of circulating free IGF-1 identify NSCLC patients who derive clinical benefit from figitumumab.

BACKGROUND: Phase III trials of the anti-insulin-like growth factor type 1 receptor (IGF-IR) antibody figitumumab (F) in unselected non-small-cell lung cancer (NSCLC) patients were recently discontinued owing to futility. Here, we investigated a role of free IGF-1 (fIGF-1) as a potential predictive biomarker of clinical benefit from F treatment. MATERIALS AND METHOD: Pre-treatment circulating levels of fIGF-1 were tested in 110 advanced NSCLC patients enrolled in a phase II study of paclitaxel and carboplatin given alone (PC) or in combination with F at doses of 10 or 20 mg kg(-1) (PCF10, PCF20). RESULTS: Cox proportional hazards model interactions were between 2.5 and 3.5 for fIGF-1 criteria in the 0.5-0.9 ng ml(-1) range. Patients above each criterion had a substantial improvement in progression-free survival on PCF20 related to PC alone. Free IGF-1 correlated inversely with IGF binding protein 1 (IGFBP-1, ρ=-0.295, P=0.005), and the pre-treatment ratio of insulin to IGFBP-1 was also predictive of F clinical benefit. In addition, fIGF-1 levels correlated with tumour vimentin expression (ρ=0.594, P=0.021) and inversely with E-cadherin (ρ=-0.389, P=0.152), suggesting a role for fIGF-1 in tumour de-differentiation. CONCLUSION: Free IGF-1 may contribute to the identification of a subset of NSCLC patients who benefit from F therapy.

Emergence of increased cerebral metastasis after high-dose preoperative radiotherapy with chemotherapy in patients with locally advanced nonsmall cell lung carcinoma.

BACKGROUND: In recent years, combined modality induction therapy has defined a new standard of care in the treatment of patients with American Joint Committee on Cancer (AJCC) Stage III nonsmall cell lung carcinoma, providing improved local control and improved disease-free survival. However, the majority of Stage III patients still die of recurrent disease. METHODS: Forty-two consecutive patients with AJCC Stage IIIA/IIIB nonsmall cell lung carcinoma (NSCLC) who were undergoing induction chemoradiotherapy followed by surgical resection of the primary NSCLC tumor between December 1, 1987 and September 1, 1999 were analyzed for resectability, survival, and patterns of disease failure. These patients received cisplatin (60 mg/m(2)) on Days 1 and 22 and etoposide (100 mg/m(2)) on Days 1, 2, and 3, and Days 22, 23, and 24 together with 5940 centigrays (cGy) of radiation in 180-cGy fractions delivered over 6 weeks. RESULTS: Thirty-one of the 42 patients (74%) underwent surgical resection of the primary lung tumor and mediastinal lymph nodes after chemoradiotherapy. No surgical deaths were reported. The median survival of these 31 patients was 52 months. The 5-year survival estimate using the Kaplan-Meier method was 49.9%. The local control rate was 80%. The incidence of distant metastases other than in the brain was reduced. The most frequently involved site of isolated first recurrence was the brain. The median time to brain recurrence was 7.5 months from the time of surgical resection. All brain metastases were detected within 2 years. CONCLUSIONS: The high incidence of isolated brain metastasis after induction chemoradiotherapy and curative resection and their response to treatment suggest that routine scans of the brain may be indicated in the follow-up of patients with locally advanced NSCLC.

Randomized phase III intergroup trial of isotretinoin to prevent second primary tumors in stage I non-small-cell lung cancer.

BACKGROUND: Promising data have suggested that retinoid chemoprevention may help to control second primary tumors (SPTs), recurrence, and mortality of stage I non-small-cell lung cancer (NSCLC) patients. METHODS: We carried out a National Cancer Institute (NCI) Intergroup phase III trial (NCI #I91-0001) with 1166 patients with pathologic stage I NSCLC (6 weeks to 3 years from definitive resection and no prior radiotherapy or chemotherapy). Patients were randomly assigned to receive a placebo or the retinoid isotretinoin (30 mg/day) for 3 years in a double-blind fashion. Patients were stratified at randomization by tumor stage, histology, and smoking status. The primary endpoint (time to SPT) and the secondary endpoints (times to recurrence and death) were analyzed by log-rank test and the Cox proportional hazards model. All statistical tests were two-sided. RESULTS: After a median follow-up of 3.5 years, there were no statistically significant differences between the placebo and isotretinoin arms with respect to the time to SPTs, recurrences, or mortality. The unadjusted hazard ratio (HR) of isotretinoin versus placebo was 1.08 (95% confidence interval [CI] = 0.78 to 1.49) for SPTs, 0.99 (95% CI = 0.76 to 1.29) for recurrence, and 1.07 (95% CI = 0.84 to 1.35) for mortality. Multivariate analyses showed that the rate of SPTs was not affected by any stratification factor. Rate of recurrence was affected by tumor stage (HR for T(2) versus T(1) = 1.77 [95% CI = 1.35 to 2.31]) and a treatment-by-smoking interaction (HR for treatment-by-current-versus-never-smoking status = 3.11 [95% CI = 1.00 to 9.71]). Mortality was affected by tumor stage (HR for T(2) versus T(1) = 1.39 [95% CI = 1.10 to 1.77]), histology (HR for squamous versus nonsquamous = 1.31 [95% CI = 1.03 to 1.68]), and a treatment-by-smoking interaction (HR for treatment-by-current-versus-never-smoking = 4.39 [95% CI = 1.11 to 17.29]). Mucocutaneous toxicity (P<.001) and noncompliance (40% versus 25% at 3 years) were higher in the isotretinoin arm than in the placebo arm. CONCLUSIONS: Isotretinoin treatment did not improve the overall rates of SPTs, recurrences, or mortality in stage I NSCLC. Secondary multivariate and subset analyses suggested that isotretinoin was harmful in current smokers and beneficial in never smokers.

FDG imaging of a pulmonary artery sarcoma.

Fluorine-18-2-fluro-2-deoxy-D-glucose-positron emission tomographic tumor imaging was employed to aid in the diagnosis of a patient with a right hilar mass. Based on preoperative imaging and intraoperative findings, a right pneumonectomy was performed for what proved to be a pulmonary artery sarcoma.

A randomized phase II trial of echinomycin, trimetrexate, and cisplatin plus etoposide in patients with metastatic nonsmall cell lung carcinoma: an Eastern Cooperative Oncology Group Study (E1587).

BACKGROUND: Patients with metastatic nonsmall cell lung carcinoma (NSCLC) usually have a poor prognosis. A chemotherapy regimen containing cisplatin is commonly used for symptom palliation. Echinomycin is a potent bifunctional intercalator of double-strand DNA; trimetrexate is a new derivative of methotrexate and is active against methotrexate-resistant tumor cells in vitro. METHODS: The Eastern Cooperative Oncology Group conducted a randomized Phase II study. Eligible patients were assigned to receive echinomycin 1200 microg/m2 by intravenous (i.v.) infusion over 30-60 minutes once a week for 4 weeks, repeated every 6 weeks; trimetrexate 12 mg/m2 i.v. bolus on Days 1-5 every 3 weeks, or 8 mg/m2 i.v. bolus on Days 1-5 for patients who had prior radiation to greater than 30% of their bone marrow; or cisplatin 60 mg/m2 i.v. on Day 1 and etoposide 120 mg/m2 i.v. on Days 1-3 every 4 weeks. Patients were evaluated before each cycle for tumor response, toxicity, and quality-of-life measurements. RESULTS: One hundred thirty-six patients were entered on the study, and 118 were evaluable for toxicity and response. The response rates were 16%, 5%, and 5% in patients treated with cisplatin and etoposide, echinomycin, and trimetrexate, respectively. There were no complete responses. The median survival was 37.9, 24.3, and 28.0 weeks for patients who received cisplatin and etoposide, echinomycin, and trimetrexate, respectively. Although cisplatin and etoposide appeared to give better therapeutic results, the response rate or survival did not reach statistical significance. This may have been due to inadequate sample size. Neither did quality-of-life measurement show any significant differences among treatments. CONCLUSIONS: Echinomycin and trimetrexate had minimal antitumor activity in patients with metastatic NSCLC: Response rate and survival remained poor in all three treatment arms. Patients should be encouraged to participate in clinical trials so that more effective therapy can be identified.

Phase II trial of docetaxel (Taxotere) in patients with adenocarcinoma of the upper gastrointestinal tract previously untreated with cytotoxic chemotherapy: the Eastern Cooperative Oncology Group (ECOG) results of protocol E1293.

The aim of this study was to evaluate the clinical efficacy and safety of docetaxel (Taxotere) in patients with adenocarcinoma of the upper gastrointestinal tract previously untreated with cytotoxic chemotherapy. Docetaxel 100 mg m-2 was administered as a 1 hour intravenous (IV) infusion every 3 weeks to 41 patients. Patients were premedicated prior to each course with dexamethasone, diphenhydramine and cimetidine. Clinical response and toxicity were determined. Objective responses were seen in seven of 41 eligible patients (two complete responses [CRs] and five partial responses [PRs], for an objective response rate of 17% (90% confidence interval [CI], 8% to 30%). The most common toxicity was grade 4 neutropenia, which occurred in 88% of patients; 46% of patients required a dose reduction following an episode of neutropenic fever requiring antibiotic therapy. Additional patients have had reversible grade 3-4 toxicities including nausea, vomiting, stomatitis, diarrhea, fatigue and peripheral neuropathy. Ten patients have had grade 1-3 hypersensitivity reactions. Alopecia has been seen in the majority of patients. Fluid retention grade 1-3 has been observed in patients. Docetaxel administered on this schedule is an active agent in adenocarcinomas of the upper gastrointestinal tract. Further investigation of this drug should be conducted in multi-drug combination programs.

Local excision of rectal carcinoma. Early results with combined chemoradiation therapy using 5-fluorouracil and leucovorin.

PURPOSE: This study was undertaken to evaluate the treatment morbidity, functional outcome, and recurrence risk of patients undergoing local excision and combined chemoradiation therapy for rectal carcinoma. METHODS: Eighteen patients underwent local excision of their rectal carcinoma. Four patients underwent local excision alone (T1-2, N0-X, low risk), 10 patients underwent local excision with postoperative chemoradiation therapy using 5-fluorouracil and leucovorin (T1-2, N0-X, high risk), and 4 patients underwent local excision, chemoradiation therapy, and six months of additional 5-fluorouracil and leucovorin (T3 or N1). RESULTS: Of the four patients undergoing local excision alone, there was no treatment morbidity or alteration in functional outcome. Of the 14 patients receiving chemoradiation therapy, three reported early Grade 3-4 toxicity manifested by cystitis, proctitis, or perineal skin desquamation. At six months, two patients reported persistent rectal urgency and occasional fecal incontinence, and 11 patients reported increasing stool frequency (average, 3: range, 2-8). The six months of additional 5-fluorouracil and leucovorin were well tolerated and did not appear to further affect functional outcome. There were no local recurrences, although one patient developed distant metastatic disease. CONCLUSION: This treatment regimen, while generally well tolerated, is associated with significant acute toxicity in certain patients. We have identified specific causative factors which can be modified to decrease acute morbidity, including the elimination of leucovorin during the combined chemoradiation therapy.

Possible myocardial toxicity associated with interleukin-4 therapy.

Interleukin (IL)-4 is a cytokine produced by T lymphocytes, which may play a role in allergic inflammatory processes through its stimulatory effects on immunoglobulin E production and mast cells. In this report, we describe a patient with metastatic melanoma involving the heart who had biopsy-proven myocarditis after treatment with high-dose IL-4. Because of the uncharacteristic predominance of polymorphonuclear and mast cells in the inflammatory infiltrate of this patient's myocardium, we postulate a unique mechanism of IL-4-associated myocarditis. Three other patients treated with IL-4 had less well-defined cardiac abnormalities, suggesting that patients receiving IL-4 may be at risk for cardiac toxicity. Additional studies will be necessary to confirm such an association.

An association between the risk of cancer and mutations in the HRAS1 minisatellite locus.

BACKGROUND: The role of mutations in protooncogenes and their regulatory sequences in the pathogenesis of cancer is under close scrutiny. Minisatellites are unstable repetitive sequences of DNA that are present throughout the human genome. The highly polymorphic HRAS1 minisatellite locus just downstream from the protooncogene H-ras-1 consists of four common progenitor alleles and several dozen rare alleles, which apparently derive from mutations of the progenitors. We previously observed an association of the rare mutant alleles with many forms of cancer, and we undertook the present study to pursue this observation further. METHODS: We conducted a case-control study, typing 736 HRAS1 alleles from patients with cancer and 652 from controls by Southern blotting of leukocyte DNA. We also carried out a meta-analysis of this study and 22 other published studies, estimating the relative risk of cancer (such as bladder, breast, or colorectal cancer) when one of the rare HRAS1 alleles was present. RESULTS: Both the present case-control study (odds ratio, 1.83; 95 percent confidence interval, 1.28 to 2.67; P = 0.002) and the present study combined with our previous study (odds ratio, 2.07; 95 percent confidence interval, 1.47 to 2.92; P < 0.001), as well as the meta-analysis of all 23 studies (odds ratio, 1.93; 95 percent confidence interval, 1.63 to 2.30; chi-square = 57.58; P < 0.001), replicated our original finding and demonstrated a significant association of rare HRAS1 alleles with cancer. We found significant associations for four types of cancer: carcinomas of the breast, colorectum, and urinary bladder and acute leukemia. We also identified suggestive but not statistically significant associations for cancers of the lung and prostate and for non-Hodgkin's lymphoma. CONCLUSIONS: Mutant alleles of the HRAS1 minisatellite locus represent a major risk factor for common types of cancer. Although the relative risk associated with the presence of one rare allele is moderate, the aggregate prevalence of one rare allele is moderate, the aggregate prevalence of this class of mutant alleles implies an extremely important attributable risk: 1 in 11 cancers of the breast, colorectum, and bladder.

N2 lung cancer: outcome in patients with false-negative computed tomographic scans of the chest.

Over the past 13 years 681 consecutive patients have undergone computed tomographic staging and surgical staging of the mediastinum. Five hundred one tested negative for mediastinal lymph node enlargement by computed tomographic staging, and 37 of these patients had cancerous mediastinal lymph nodes at thoracotomy (n = 36) or mediastinoscopy (n = 1). The survival in this group of patients was analyzed according to T status, central or peripheral location of tumor, cell type, areas of mediastinum that are involved, and extent of nodal involvement with tumor. Twelve patients had central tumors, and 25 had peripheral tumors. Two of the patients in the central tumor group died postoperatively and only 2 others survived, whereas 12 of the 25 patients in the peripheral tumor group survived. Four of the 37 patients, 2 in each group, did not undergo resection, and all died. All but 2 of the 31 survivors who underwent resection received postoperative adjuvant x-ray therapy (23 patients), chemotherapy (1 patient), or x-ray therapy and chemotherapy (5 patients). The projected 2-year and 5-year survivals (Kaplan-Meier) were 40% and 28% for patients overall, 46% and 31% for those whose tumors were resected, 40% and 20% for those with resected central tumors, and 52% and 45% for those with resected peripheral tumors. None of these differences was significant. Cell type, location or number of locations of involved nodes, and the average percentage or maximum percentage of mediastinal node that was involved with tumor did not influence survival. The high negative predictive index for computed tomographic staging of the mediastinal lymph nodes and the observed 2-year and 5-year survivals in patients with false-negative computed tomographic scans of the chest justifies definitive thoracotomy without mediastinoscopy in most patients with a normal mediastinum on computed tomographic scan.