title: Value of surveillance studies for patients with stage I to II diffuse large B-cell lymphoma in the rituximab era.
abstract: BACKGROUND
  The role of surveillance studies in limited-stage diffuse large B-cell lymphoma (DLBCL) in the rituximab era has not been well defined. We sought to evaluate the use of imaging (computed tomography [CT] and positron emission tomography [PET]-CT) scans and lactate dehydrogenase (LDH) in surveillance of patients with stage I to II DLBCL.
  
  
  METHODS
  A retrospective analysis was performed of patients who received definitive treatment between 2000 and 2013.
  
  
  RESULTS
  One hundred sixty-two consecutive patients with stage I to II DLBCL were treated with chemotherapy +/- rituximab, radiation, or combined modality therapy. The 5-year rates of overall survival (OS) and freedom from progression (FFP) were 81.2% and 80.8%, respectively. Of the 162 patients, 124 (77%) were followed up with at least 1 surveillance PET scan beyond end-of-treatment scans; of those, 94 of 124 (76%) achieved a complete metabolic response on PET scan after completion of chemotherapy, and this was associated with superior FFP (P=.01, HR=0.3) and OS (P=.01, HR 0.3). Eighteen patients experienced relapse after initial response to therapy. Nine relapses were initially suspected by surveillance imaging studies (8 PET, 1 CT), and 9 were suspected clinically (5 by patient-reported symptoms and 4 by symptoms and physical examination). No relapses were detected by surveillance LDH. The median duration from initiation of treatment to relapse was 14.3 months among patients with relapses suspected by imaging, and 59.8 months among patients with relapses suspected clinically (P=.077). There was no significant difference in OS from date of first therapy or OS after relapse between patients whose relapse was suspected by imaging versus clinically. Thirteen of 18 patients underwent successful salvage therapy after relapse.
  
  
  CONCLUSIONS
  A complete response on PET scan immediately after initial chemotherapy is associated with superior FFP and OS in stage I to II DLBCL. The use of PET scans as posttreatment surveillance is not associated with a survival advantage. LDH is not a sensitive marker for relapse. Our results argue for limiting the use of posttreatment surveillance in patients with limited-stage DLBCL.
authors: Department of Radiation Oncology, Stanford Cancer Institute, Stanford, California.
authors: Susan M
authors: SM
authors: Hiniker
authors: Department of Radiation Oncology, Stanford Cancer Institute, Stanford, California.
authors: Erqi L
authors: EL
authors: Pollom
authors: Division of Oncology, Department of Medicine, Stanford Cancer Institute, Stanford, California.
authors: Michael S
authors: MS
authors: Khodadoust
authors: Department of Radiation Oncology, Stanford Cancer Institute, Stanford, California.
authors: Margaret M
authors: MM
authors: Kozak
authors: Division of Nuclear Medicine, Department of Radiology, Stanford Cancer Institute, Stanford, California.
authors: Guofan
authors: G
authors: Xu
authors: Division of Nuclear Medicine, Department of Radiology, Stanford Cancer Institute, Stanford, California.
authors: Andrew
authors: A
authors: Quon
authors: Division of Oncology, Department of Medicine, Stanford Cancer Institute, Stanford, California.
authors: Ranjana H
authors: RH
authors: Advani
authors: Department of Radiation Oncology, Stanford Cancer Institute, Stanford, California. Electronic address: rhoppe@stanford.edu.
authors: Richard T
authors: RT
authors: Hoppe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood; D003131:Combined Modality Therapy / Q000379:methods; D003520:Cyclophosphamide / Q000008:administration & dosage; D018572:Disease-Free Survival; D004317:Doxorubicin / Q000008:administration & dosage; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D016403:Lymphoma, Large B-Cell, Diffuse / Q000000981:diagnostic imaging* / Q000201:enzymology / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D011159:Population Surveillance / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods; D011241:Prednisone / Q000008:administration & dosage; D012008:Recurrence; D012189:Retrospective Studies; D000069283:Rituximab; D016879:Salvage Therapy / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D014750:Vincristine / Q000008:administration & dosage
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D014408:Biomarkers, Tumor; C571759:R-CHOP protocol; D000069283:Rituximab; D014750:Vincristine; D005047:Etoposide; D004317:Doxorubicin; D003520:Cyclophosphamide; D007770:L-Lactate Dehydrogenase; D011241:Prednisone