Leung, Nelson

AbstractWaldenström macroglobulinemia (WM) is an immunoglobulin M‐associated lymphoma, with majority of cases demonstrating MYD88 locus alteration, most commonly, MYD88L265P. Owing to low prevalence of the wild‐type (WT) MYD88 genotype in WM, clinically relevant data in this patient population are sparse, with one study showing nearly a 10‐fold increased risk of mortality in this subgroup compared to patients with MYD88L265P mutation. We studied a large cohort of patients with MYD88L265P and MYD88WT WM, evaluated at Mayo Clinic, Rochester, between 1995 and 2016, to specifically assess the impact of these genotypes on clinical course. Of 557 patients, MYD88L265P mutation status, as determined by allele‐specific polymerase chain reaction, was known in 219, and 174 (79%) of those exhibited MYD88L265P, 157 of 174 patients had active disease. Of 45 (21%) patients with MYD88WT genotype, 44 had active disease. The estimated median follow‐up was 7.0 years; median overall survival was 10.2 years (95% CI: 8.4‐16.5) for MYD88L265P versus 13.9 years (95% CI: 6.4‐29.3) for the MYD88WT (P = 0.86). The time‐to‐next therapy from frontline treatment and the presenting features were similar in the two patient populations. For patients with smoldering WM at diagnosis, the median time‐to‐progression to active disease was 2.8 years (95% CI: 2.2‐3.8) in the MYD88L265P cohort and 1.9 years (95% CI: 0.7‐3.1) in the MYD88WT cohort (P = 0.21). The frequency of transformation to high‐grade lymphoma, or the development of therapy‐elated myelodysplastic syndrome was higher in the MYD88WT cohort (16% versus 4% in the MYD88L265P, P = 0.009). In conclusion, MYD88L265P mutation does not appear to be a determinant of outcome, and its presence may not be a disease‐defining feature in WM. Our findings warrant external validation, preferably through prospective studies.

AbstractExperience with intensive chemotherapy for relapsed/refractory multiple myeloma (RRMM) using VDT PACE regimen and its modifications (VDT PACE‐like regimens: VPLRs) outside TOTAL THERAPY trials is limited. We analyzed the outcomes of 141 patients with RRMM who received VPLRs at our center between 2006 and 2017 in an intent‐to‐treat analysis. Median age was 59.7 years and 66.7% of patients were male. A median of 2.2 years (range 0.02‐11.4) separated diagnosis of myeloma and inititation of VPLR. High‐risk cytogenetics were present in 52.4% patients. Patients received a median of 4 (range 1‐14) prior therapies, including stem cell transplant (SCT) in 66.7% patients. Ninety‐five (67.4%) patients received VDT PACE, 20 (14.2%) patients received VD PACE and 26 (18.4%) patients received other VPLRs. Patients received a median of 1 cycle (range 1‐9) of VPLR. We observed ≥ minimal response in 68.4%, ≥ partial response (PR) in 54.4% and ≥ very good PR in 10.3% patients. Median progression‐free survival was 3.1 months (95% CI, 1.9‐3.9) and median overall survival (OS) was 8.1 months (CI, 6.2‐9.9). One‐hundred and sixteen (82.3%) patients received some therapy after VPLR; 71 (61.2%) received systemic chemotherapy, while 45 (38.8%) underwent SCT. Median OS for those who received SCT after VPLR was 15.1 months (CI, 10.3‐20.8). Age ≥ 60 years (hazard ratio [HR] 2.3 [CI, 1.4‐3.7]; P = 0.0008) and R‐ISS III stage (HR‐ 2.4 [CI, 1.3‐4.0]; P = 0.003) predicted shorter OS in patients receiving VPLR. VPLRs are effective in heavily pre‐treated RRMM. In fit patients, SCT can be used to consolidate the response to VPLR.

Purpose: To describe ophthalmic manifestations of systemic amyloidosis, a group of devastating conditions. Methods: A retrospective chart review including patients who had ocular examinations at Mayo Clinic between January 1, 1985, and April 1, 2014, and a diagnosis of light-chain (AL), secondary (AA), or nontransthyretin familial amyloidosis was undertaken. Sixty-eight patients with AL amyloidosis, eight patients with AA amyloidosis, and five patients with nontransthyretin familial amyloidosis were included. Results: Of 68 patients, 8 patients (14 eyes) with AL amyloidosis had ocular involvement secondary to conjunctiva, temporal artery, extraocular muscle, trabecular meshwork, and cranial nerve deposition. One of the five patients with nontransthyretin familial amyloidosis had gelsolin-related corneal dystrophy. No patients with AA amyloidosis (n = 8) had ophthalmic manifestations. Conclusion: Systemic amyloidosis can lead to ocular morbidity. Patients with AL amyloidosis had involvement of the temporal artery, conjunctiva, extraocular muscles, trabecular meshwork, and cranial nerves. Those with gelsolin nontransthyretin familial amyloidosis were susceptible to corneal dystrophy. Patients with AA amyloidosis did not manifest ophthalmic involvement. Finally, if ocular amyloidosis is detected, patients should be referred for systemic workup.

Abstract Background Fluoroquinolones (FQ) are among the most commonly prescribed antibiotics. Nephrotoxicity related to FQ use is infrequently reported and the mechanism of renal injury is incompletely elucidated. We describe clinical manifestations and outcome of patients with biopsy proven acute interstitial nephritis (AIN) associated with FQ use at our institution. Methods We conducted a retrospective review of biopsy-proven AIN attributed to FQ use at Mayo Clinic Rochester from 1993 to 2016. Cases were reviewed by a renal pathologist and attributed to FQ use by an expert nephrologist. We also reviewed and summarized all published case reports of biopsy proven AIN that were attributed to FQ use. Results We identified 24 patients with FQ-related biopsy-proven AIN. The most commonly used FQ was ciprofloxacin (71%) with median antibiotic treatment duration of 7 days (Figure 1). The median duration between starting FQ and the diagnosis of AIN was 8.5 (IQR: 17). Common clinical manifestations included fever (50%), flank pain (8%), and skin rash (21%). However, 17% of the patients were asymptomatic at the time of diagnosis (Figure 2). Majority (58%) of the patients recovered following discontinuation of antibiotics and returned to baseline renal function at a median of 20.5 (IQR: 15.5). Six patients required temporary hemodialysis and 9 patients received steroids. Conclusion Onset of FQ-related AIN can be delayed and a high index of suspicion is needed by physicians prescribing these agents. Overall outcomes are favorable with recovery to baseline renal function within 3 weeks of discontinuing the offending drug. Disclosures All authors: No reported disclosures.

AbstractAchievement of a normal FLC ratio (FLCr) following treatment indicates hematologic response and suggests better outcomes in light chain amyloidosis (AL). We examined if elevated involved free light chain (hiFLC) impacts outcomes in patients achieving normal FLCr. We retrospectively analyzed 345 AL patients who were diagnosed within a 10‐year period (2006‐2015) and had 2 consecutive normal FLCr values after 1st line treatment. Among these, patients with hiFLC at 1st reading of normal FLCr (hiFLC1; n = 166; 48.1%) were compared to those who did not (n = 179; 51.9%). Patients with AL who have hiFLC1 after initial therapy had higher rates of multi‐organ involvement (63.3 vs 46.4%; P = .002) and patients in advanced Mayo stage (42.9 vs 32.2%; P = .04) at diagnosis. The median progression free survival [PFS; 38.2 (95%CI; 26.4, 55.4) vs 67.1 (95%CI; 55.8, 88) months; P = .0002] and overall survival [OS; 94.4 (95%CI; 78, 107.1) vs not reached (NR, 95%CI; 116.1, NR) months; P < .0001] were lower in those who had hiFLC1. A more stringent comparison for patients with 2 consecutive hiFLC (hIFLC2; n = 111; 32.2%) versus not (n = 2234; 67.8%) showed consistent results [PFS; 27.1 (95%CI; 23, 53.8) vs 63.3 (95%CI; 55.4, 77) months; P < .0001 and OS; 78 (95% CI; 54.6, 98.8) vs NR (95%CI; NR, NR); P < .0001]. This poor prognostic impact of hiFLC on survival was independent of serum creatinine, Mayo stage, negative immunofixation status and inclusion of transplant in initial therapy on multivariate analysis. Hence, persistent elevation of iFLC predicts poor prognosis even among patients achieving normal ratio after initial therapy in AL.

Key Points Organ progression at second-line therapy predicated inferior survival. Patients relapsing from >VGPR had a longer time to develop organ progression.

AbstractOutside of clinical trials, experience with daratumumab‐based combination therapies (DCTs) using bortezomib (V)/lenalidomide (R)/pomalidomide (P), and dexamethasone (d) in relapsed/refractory multiple myeloma (RRMM) is limited. We reviewed the outcomes of 126 patients who received ≥ 1 cycle of any DCT. Median age at DCT initiation was 67 (range, 43‐93) years. High‐risk cytogenetics was present in 33% patients. Median number of prior therapies was 4 (range, 1‐14) and time to first DCT from diagnosis was 4.3 years (range, 0.4‐13.0). Seventeen (13%) patients were refractory to single agent daratumumab. Fifty‐two (41%), 34 (27%), 23 (18%), and 17 (14%) received DPd, DRd, DVd and “other” DCTs, respectively. Overall response rate was 47%. Median follow‐up was 5.5 months (95% CI, 4.2‐6.1). Median progression‐free survival (PFS) was 5.5 months (95% CI, 4.2‐7.8). Median overall survival was not reached (NR) with any regimen. Median PFS (months) was worst for penta‐refractory MM (n = 8) vs quadruple refractory MM (n = 18) and others (n = 100) (2.2 [95% CI, 1‐2.4] vs 3.1 [95% CI, 2.1‐NR] vs 5.9 [95% CI, 5.0‐NR]; P < .001); those who were refractory to ≥1 agents used in the DCT vs others (4.9 [95% CI, 3.1‐6.0] vs 8.2 [95% CI, 4.6‐NR]; P = .02); and those who received >2 prior therapies vs others (5.0 months [95% CI, 3.7‐5.9] vs NR [95% CI, NR‐NR]; P = .002). Non‐hematologic toxicities included infections (38%), fatigue (32%), and infusion reactions (18%). Grade 3 or higher hematological toxicities were seen in 41% of patients. DCTs are effective in RRMM. ORR and PFS in heavily pretreated patients are lower than those reported in clinical trials.

SummaryThe management of Waldenström macroglobulinaemia (WM) relies predominantly on small trials, one of which has demonstrated activity of dexamethasone, rituximab and cyclophosphamide (DRC) in the frontline setting. We report on the efficacy of DRC, focusing on relapsed/refractory (R/R) patients. Ibrutinib, a recently approved agent in WM demonstrated limited activity in patients with MYD88WT genotype. Herein, we additionally report on the activity of DRC based on the MYD88L265P mutation status. Of 100 WM patients evaluated between January 2007 and December 2014 who received DRC, 50 had R/R WM. The overall response rate (ORR) was 87%. The median progression‐free survival (PFS) and time‐to‐next‐therapy (TTNT) were 32 (95% confidence interval [CI]: 15–51) and 50 (95% CI: 35–60) months, respectively. In the previously untreated cohort (n = 50), the ORR was 96%, and the median PFS and TTNT were 34 months (95% CI: 23–not reached [NR]) and NR (95% CI: 37–NR), respectively. Twenty‐five (86%) of 29 genotyped patients harbored MYD88L265P. The response rates and outcomes were independent of MYD88 mutation status. Grade ≥3 adverse effects included neutropenia (20%), thrombocytopenia (7%) and infections (3%). Similar to the frontline setting, DRC is an effective and well‐tolerated salvage regimen for WM. In contrast to ibrutinib, DRC offers a less expensive, fixed‐duration option, with preliminary data suggesting efficacy independent of the patients’ MYD88 status.