Clearance of Hepatitis C Virus (HCV) Is Associated With Improved Outcomes in HCV-Associated Lymphoma

BACKGROUND

Improved hepatitis C virus (HCV) clearance due to directly acting antiviral agents has led to remarkably improved outcomes of indolent HCV-associated non-Hodgkin lymphoma (NHL). The impact of directly acting antivirals on the outcomes of aggressive NHL is still under investigation. Characteristics of HCV-associated NHL in black patients are not well characterized. We report outcomes of HCV-associated NHL compared to their HCV-negative counterparts in a predominantly black population.

PATIENTS AND METHODS

Patients with lymphoma between January 2007 and December 2017 were retrospectively studied. Depending on presence or absence of HCV RNA, patients were grouped into HCV positive (HCV⁺) and HCV negative (HCV^-) cohorts. Depending on virologic clearance (VC), HCV⁺ were classified into HCV⁺ with VC and HCV⁺ without VC. Overall response rate (ORR), complete response, overall survival (OS), and progression-free survival (PFS) of HCV⁺ patients with and without VC were compared to HCV^- patients.

RESULTS

Of 397 patients with lymphoma, 40 had HCV. Black comprised 90% of HCV⁺ patients. Diffuse large B-cell lymphoma was most frequent (47%) in the HCV⁺ group. HCV⁺ patients without VC had significantly worse OS and PFS compared to HCV^- patients. There were no differences in ORR, complete response, PFS, and OS of HCV⁺ patients with VC and HCV^- patients. These results were consistent in subgroups of diffuse large B-cell lymphoma and aggressive lymphoma.

CONCLUSION

HCV clearance is positively associated with lymphoma outcomes in black patients. Patients who clear HCV have noninferior outcomes to HCV^- patients, while those who fail to clear HCV have significantly worse outcomes.

TLD and OSLD dosimetry systems for remote audits of radiotherapy external beam calibration

The Imaging and Radiation Oncology Core QA Center in Houston (IROC-H) performs remote dosimetry audits of more than 20,000 megavoltage photon and electron beams each year. Both a thermoluminescent dosimeter (TLD-100) and optically stimulated luminescent dosimeter (OSLD; nanoDot) system are commissioned for this task, with the OSLD system being predominant due to the more time-efficient read-out process. The measurement apparatus includes 3 TLD or 2 OSLD in an acrylic mini-phantom, which are irradiated by the institution under reference geometry. Dosimetry systems are calibrated based on the signal-to-dose conversion established with reference dosimeters irradiated in a Co-60 beam, using a reference dose of 300 cGy for TLD and 100 cGy for OSLD. The uncertainty in the dose determination is 1.3% for TLD and 1.6% for OSLD at the one sigma level. This accuracy allows for a tolerance of ±5% to be used.