Performance characteristics of a tumor-informed circulating tumor DNA (ctDNA) minimal residual disease (MRD) assay in invasive bladder cancer in clinical practice

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Background: Detection of minimal residual disease (MRD) is emerging as a potential risk stratification and surveillance tool in patients with resected bladder cancer to potentially direct adjuvant therapy and early intervention. Recently, the sensitivity of MRD testing for early detection of recurrence has been questioned. We sought to evaluate the real world diagnostic performance characteristics of the Signatera ctDNA assay in patients with stage 1-4 bladder cancer who either had transurethral resection of bladder tumor (TURBT) in addition to either chemoradiation or radical cystectomy. Methods: Patients with bladder cancer who underwent ctDNA MRD testing after resection for stage 1-4 disease from 03/2021 to 09/2022 were evaluated retrospectively. Both patients with single and serial ctDNA assays were included. Individual chart review was performed to collect demographic and clinical variables such as diagnosis, stage, pathology, imaging results, and treatment course. Results: MRD results from 19 patients were available, 9 of which had serial assays. 13/19 patients were found to have ctDNA positive results at any time point. The positivity rate at initial testing was associated with stage: Stage 1: 3/5 patients, of which 2 had TURBT and 1 Radical cystectomy, stage 2: 2/5, stage 3: 6/8, and stage 4: 0/1. Notably, of the 9 patients with serial assays, one patient’s result converted from negative to highly positive during surveillance, with subsequent decrease to low positive after adjuvant therapy. One patient had a result of 2 consecutive low positives initially, which was converted to negative after systemic therapy and radiation. 7/19 patients completed testing 3 or more times over a span of approximately 4-13 months, 2 of whom had negative results throughout. Most patients who were found to have positive ctDNA did demonstrate radiographic recurrence within 2-3 months of ctDNA detection. Conclusions: Positive ctDNA MRD after resection is common in bladder cancer. Tumor-informed ctDNA MRD testing has very high sensitivity, but a one-time negative test result does not exclude the presence of metastatic disease. The above data shows an association between cancer stage and positivity results, particularly for advanced stages. Stage I cases with positive results can likely be explained by inadequate resection. Increases in ctDNA may represent early recurrence and can potentially be salvaged with early systemic therapy reverting to negative ctDNA. Prospective randomized and non-randomized studies are evaluating the clinical utility of ctDNA MRD testing in bladder cancer, and analysis of Signatera ctDNA assays will largely contribute to these efforts.

Phase II Randomized Trial of Sequential or Concurrent FOLFOXIRI-Bevacizumab Versus FOLFOX-Bevacizumab for Metastatic Colorectal Cancer (STEAM)

BACKGROUND

First-line treatment for metastatic colorectal cancer (mCRC) typically entails a biologic such as bevacizumab (BEV) with 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX) or 5-fluorouracil/leucovorin/irinotecan (FOLFIRI). STEAM (NCT01765582) assessed the efficacy of BEV plus FOLFOX/FOLFIRI (FOLFOXIRI), administered concurrently (cFOLFOXIRI-BEV) or sequentially (sFOLFOXIRI-BEV, FOLFOX-BEV alternating with FOLFIRI-BEV), versus FOLFOX-BEV for mCRC.

PATIENTS AND METHODS

Patients with previously untreated mCRC (n = 280) were randomized 1:1:1 to cFOLFOXIRI-BEV, sFOLFOXIRI-BEV, or FOLFOX-BEV and treated with 4-6-month induction followed by maintenance. Coprimary objectives were overall response rate (ORR; first-line cFOLFOXIRI-BEV vs. FOLFOX-BEV) and progression-free survival (PFS; pooled first-line cFOLFOXIRI-BEV and sFOLFOXIRI-BEV vs. FOLFOX-BEV). Secondary/exploratory objectives included overall survival (OS), liver resection rates, biomarker analyses, and safety.

RESULTS

ORR was 72.0%, 72.8%, and 62.1% and median PFS was 11.9, 11.4, and 9.5 months with cFOLFOXIRI-BEV, sFOLFOXIRI-BEV, and FOLFOX-BEV, respectively. OS was similar between arms. ORR between cFOLFOXIRI-BEV and FOLFOX-BEV did not significantly differ (p = .132); thus, the primary ORR endpoint was not met. cFOLFOXIRI-BEV and sFOLFOXIRI-BEV numerically improved ORR and PFS, regardless of RAS status. Median PFS was higher with pooled concurrent and sequential FOLFOXIRI-BEV versus FOLFOX-BEV (11.7 vs. 9.5 months; hazard ratio, 0.7; 90% confidence interval, 0.5-0.9; p < .01). Liver resection rates were 17.2% (cFOLFOXIRI-BEV), 9.8% (sFOLFOXIRI-BEV), and 8.4% (FOLFOX-BEV). Grade ≥ 3 treatment-emergent adverse events (TEAEs) were observed in 91.2% (cFOLFOXIRI-BEV), 86.7% (sFOLFOXIRI-BEV), and 85.6% (FOLFOX-BEV) of patients, with no increase in serious chemotherapy-associated TEAEs.

CONCLUSION

cFOLFOXIRI-BEV and sFOLFOXIRI-BEV were well tolerated with numerically improved ORR, PFS, and liver resection rates versus FOLFOX-BEV, supporting triplet chemotherapy plus BEV as a first-line treatment option for mCRC. IMPLICATIONS FOR PRACTICE: The combination of first-line FOLFIRI with FOLFOX and bevacizumab (concurrent FOLFOXIRI-BEV) improves clinical outcomes in patients with metastatic colorectal cancer (mCRC) relative to FOLFIRI-BEV or FOLFOX-BEV, but it is thought to be associated with increased toxicity. Alternating treatment of FOLFOX and FOLFIRI (sequential FOLFOXIRI-BEV) could improve tolerability. In the phase II STEAM trial, which is the largest study of FOLFOXIRI-BEV in patients in the U.S., it was found that both concurrent and sequential FOLFOXIRI-BEV are active and well tolerated in patients with previously untreated mCRC, supporting the use of these regimens as potential first-line treatment options for this population.

Testicular Cancer, Version 2.2015

Germ cell tumors (GCTs) account for 95% of testicular cancers. Testicular GCTs constitute the most common solid tumor in men between the ages of 20 and 34 years, and the incidence of testicular GCTs has been increasing in the past 2 decades. Testicular GCTs are classified into 2 broad groups--pure seminoma and nonseminoma--which are treated differently. Pure seminomas, unlike nonseminomas, are more likely to be localized to the testis at presentation. Nonseminoma is the more clinically aggressive tumor associated with elevated serum concentrations of alphafetoprotein (AFP). The diagnosis of a seminoma is restricted to pure seminoma histology and a normal serum concentration of AFP. When both seminoma and elements of a nonseminoma are present, management follows that for a nonseminoma. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Testicular Cancer outline the diagnosis, workup, risk assessment, treatment, and follow-up schedules for patients with both pure seminoma and nonseminoma.

Kidney cancer, version 2.2014

These NCCN Guidelines Insights highlight treatment recommendations and updates specific to the management of patients with advanced non-clear cell carcinoma included in the 2014 version of the NCCN Clinical Practice Guidelines in Oncology for Kidney Cancer.

Two phase 2 trials of the novel Akt inhibitor perifosine in patients with advanced renal cell carcinoma after progression on vascular endothelial growth factor-targeted therapy

BACKGROUND

The clinical activity of allosteric inhibitors of mammalian target of rapamycin (mTOR) inhibitors in renal cell carcinoma (RCC) may be limited by upstream activation of phosphatidylinositol 3 (PI3)-kinase/Akt resulting from mTOR1 inhibition. On the basis of this rationale, 2 independent phase 2 trials (Perifosine 228 and 231) were conducted to assess the efficacy and safety of the novel Akt inhibitor perifosine in patients with advanced RCC who had failed on previous vascular endothelial growth factor (VEGF)-targeted therapy.

METHODS

In the Perifosine 228 trial, 24 patients with advanced RCC received oral perifosine (100 mg daily). Perifosine 231 enrolled 2 groups that received daily oral perifosine (100 mg daily): Group A comprised 32 patients who had received no prior mTOR inhibitor, and Group B comprised 18 patients who had received 1 prior mTOR inhibitor.

RESULTS

In the Perifosine 228 trial, 1 patient achieved a partial response (objective response rate, 4%; 95% confidence interval, 0.7%-20%), and 11 patients (46%) had stable disease as their best response. The median progression-free survival was 14.2 weeks (95% confidence interval, 7.7-21.6 weeks). In the Perifosine 231 trial, 5 patients achieved a partial response (objective response rate, 10%; 95% confidence interval, 4.5%-22.2%) and 16 patients (32%) had stable disease as their best response. The median progression-free survival was 14 weeks (95% confidence interval, 12.9, 20.7 weeks). Overall, perifosine was well tolerated, and there were very few grade 3 and 4 events. The most common toxicities included nausea, diarrhea, musculoskeletal pain, and fatigue.

CONCLUSIONS

Although perifosine demonstrated activity in patients with advanced RCC after failure on VEGF-targeted therapy, its activity was not superior to currently available second-line agents. Nonetheless, perifosine may be worthy of further study in RCC in combination with other currently available therapies.

Phase II study of perifosine in metastatic renal cell carcinoma (RCC) progressing after prior therapy (Rx) with a VEGF receptor inhibitor

5034

Background: Perifosine, a synthetic alkylphospholipid, inhibits or modulates a number of different signal transduction pathways (AKT, MAPK and JNK). In a prior trial, 15 RCC patients (pts) were enrolled in a randomized dose finding study, 9 were evaluable for response and 3 (33%) had a partial response (PR). Thus phase II trials were begun for pts who had been treated with one prior VEGFr inhibitor (Group A) or with a prior VEGFr inhibitor and prior mTOR inhibitor (Group B). We report the results of Group A (closed), and Group B (enrollment open). Methods: To measure the objective response rate (RECIST) and PFS to single agent perifosine (100 mg qhs with food) after 3 mos of Rx; Prior Rx with vaccine therapy, bevacizumab and/or cytokines was permitted. Normal organ/marrow function was required. Results: From 12/07–12/08, 46 pts (31 Group A/ 15 Group B) were treated at 13 sites. Median age 64 (range 46–80) and 36 were male; Median prior Rx was 2 (range 1 - 5); Clear cell = 37, non clear cell = 6, data n/a = 3. Prior sunitinib = 35, prior sorafenib = 10, 1 unknown due to blinded study. Prior mTOR; Tem = 9 and Rad001 = 6. As of 12/08, 44 pts were evaluable for response and PFS (two pts not eval; 1 withdrew consent, 1 toxicity < 5 days on Rx). Results listed in the table below. As of 12/08, 12/44 pts (5 Group A/ 7 Group B) remain on treatment. Median survival; not reached. Most common toxicity was grade 1 & 2 nausea (56%), arthralgia (47%), vomiting (36%), fatigue (33%) and cognitive changes (28%). Grade 3 & 4 toxicity was uncommon; arthralgia (14%) and hyperuricemia/gout (8%). Conclusions: Perifosine, similar to mTOR inhibitors, appears to have clinical benefit in mRCC as reflected by the PR rate and a 15 wk median overall PFS. This is most notably in patients who failed both a prior VEGFr and mTOR inhibitor where 7/14 remain on study as of 12/08. Randomized studies are under consideration to further evaluate perifosine's clinical benefit as 2nd or 3rd line therapy of mRCC.

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Neoadjuvant dose-dense sequential biweekly epirubicin and cyclophosphamide followed by docetaxel and trastuzumab for HER2+ operable breast cancer

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Background: Neoadjuvant (Neo) chemotherapy (CT) with trastuzumab (H) improves pathologic complete response (pCR) rate for HER2+ breast cancer. Dose-dense regimens improve outcome in the adjuvant setting but have not been fully evaluated as preoperative therapy. We designed this regimen to utilize full doses of active agents including docetaxel (T) and H in a novel biweekly schedule to explore efficacy and safety. Methods: Patients (pts) with biopsy proven, clinical stage IIA-IIIC, noninflammatory breast cancer were eligible. HER2+ by FISH was determined locally. CT consisted of epirubicin (E) 100 mg/m2 and cyclophosphamide (C) 600 mg/m2 Q 14 days x 4 followed by T 75 mg/m2 and H 6 mg/kg loading dose, then 4 mg/kg Q 14 days x 4, all with pegfilgrastim support. Surgery was scheduled 20–24 weeks from start after a fifth cycle of H 4mg/kg. EF was measured prior to CT, after EC, after TH and at 6, 12 and 24 months after surgery. Additional adjuvant H to complete 1 year of therapy by conventional schedule was recommended after surgery. The primary endpoint was pCR for invasive cancer in breast and lymph nodes. Results: 30 pts were enrolled at 5 centers: median age was 50.1 (range, 31–72); ethnicity African-American 14, Caucasian 14, other 2; clinical stage IIA, 14, IIB, 4, IIIA, 7, IIIB/C, 5; ER+ 18, PR+ 14; grade 3, 21 and grade 2, 8. Twenty eight pts were evaluable for pathologic response- 2 withdrew before completing treatment, 1 for toxicity. Dose delivery on schedule was >95% for all drugs. Clinical response prior to surgery was cCR 20; cPR 5; and stable 2 pts. Pathologic response: pCR 16 (57%) including 4 with residual DCIS only; 9 pPR, and 2 stable. Mean EF was 63.1 (range, 51–81) before treatment, 62.4 (49–75) after EC and 58.3 (35–74) after TH. Two pts had EF <50% during Neo, one with clinical CHF and 1 additional pt developed CHF during adjuvant single agent H. Both pts had symptomatic improvement with cessation of H. Adverse events were generally mild with 14 grade 3 AEs including 3 episodes of dyspnea and no grade 3 skin toxicity or any grade 4 toxicity noted. Conclusions: Sequential Neo dose-dense Q 14 day EC followed by Q 14 day TH yields a high pCR rate in HER2+ breast cancer with acceptable toxicity profile and no new safety signals noted.

No significant financial relationships to disclose.

Serum creatinine and blood urea nitrogen over a six-year period in the very old. Creatinine and BUN in the very old

In a population of 141 very elderly subjects, there was a small but significant decline in BUN and creatinine at 3 years, which persisted at 6 years although partially attenuated. A similar pattern of falling BUN and creatinine was seen in the 31 subjects who began the study with mild azotemia. There was no significant change in the subjects' mean Body Mass Index during the 6-year period of observation. The azotemic subjects had a rate of death or dropout from the study similar to that of the entire cohort. Mean systolic blood pressure fell by 5.4 mm Hg (p < 0.05) and diastolic blood pressure by 2.1 mm Hg (p = NS) by 6 years. Users of diuretics or NSAID had a mean BUN and creatinine comparable to those not taking these medications. We conclude that BUN and serum creatinine do not necessarily increase with time in the old old, even in those with mild azotemia, hence, several determinations of these parameters may be needed to ensure accuracy. While renal function in the elderly probably does not improve with time, it may stabilize due to improvement in blood pressure. Use of diuretics and NSAID by functioning elderly individuals is not necessarily associated with worsening azotemia.