Primary Bone Lymphoma — Treatment and Outcome

Nomogram-Based Prediction of Overall and Cancer-Specific Survival in Patients with Primary Bone Diffuse Large B-Cell Lymphoma: A Population-Based Study

Background

Primary bone diffuse large B-cell lymphoma (PD-DLBCL) accounts for more than 80% of primary bone lymphoma. We created two nomograms to predict overall survival (OS) and cancer-specific survival (CSS) in patients with PD-DLBCL for this rare disease.

Methods

In total, 891 patients diagnosed with PB-DLBCL between 2007 and 2016 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox analyses were performed to explore independent prognostic factors and create nomograms for OS and CSS. The area under the curve (AUC), the calibration curve, decision curve analysis (DCA), and Kaplan-Meier (K-M) curve analysis were used to evaluate the nomograms.

Results

Four variables were identified as independent prognostic factors for OS, and three variables were identified as independent prognostic factors for CSS. The receiver operating characteristic (ROC) curves demonstrated the strong discriminatory power of the nomograms. The calibration and DCA curves showed that the nomograms had a satisfactory ability to predict OS and CSS. The K-M curves showed that age, gender, primary site, chemotherapy, and tumor stage affected patient survival.

Conclusions

In patients with PD-DLBCL, age, race, primary site, and chemotherapy affected OS, while age, race, and chemotherapy affected CSS. The two nomograms created based on the aforementioned variables provided more accurate individual survival predictions for PD-DLBCL patients and can help physicians make appropriate clinical decisions.

A Nomogram Predicting Overall and Cancer-Specific Survival of Patients with Primary Bone Lymphoma: A Large Population-Based Study

We aimed to develop a nomogram for evaluating the overall survival (OS) and cancer-specific survival (CSS) in patients with primary bone lymphoma (PBL). Patients diagnosed with PBL between 2007 and 2016 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. All patients were randomly allocated to the training cohort and validation cohort (2 : 1). The nomogram was developed by the training cohort and validated by the validation cohort using the concordance index (C-index), calibration plots, and decision curve analyses (DCAs). The C-index for CSS and OS prediction in the training cohort were 0.76 and 0.77, respectively; in the validation cohort, they were 0.76 and 0.79, respectively. The calibration curve showed good consistency between nomogram prediction and actual survival. The DCA indicated obvious net benefits of the new predictive model. The nomogram showed favorable applicability and accuracy, and it will be a reliable tool for predicting OS and CSS in patients with PBL.

[Adult non-Hodgkin bone lymphomas]

Two forms of bone lymphomas can be distinguished: the primary bone lymphoma (PBL) and the secondary bone lymphoma (SBL). PBL is a rare disease with a good prognosis. Clinical manifestations and imaging findings are usually non-specific. Patient can present with pain, swelling of affected bone or pathologic fracture. Positron emission tomography-CT scan is a sensitive imaging modality and very useful for staging, restaging, surveillance of recurrence, and monitoring of treatment response of lymphoma. The diagnosis of PBL is often difficult and made after biopsy examination. Most patients have diffuse large B-cell lymphoma. Patients have been treated with radiotherapy, chemotherapy or combination of both. Localized disease, low IPI (International Prognostic Index) and complete remission after initial treatment were associated with a better outcome. Management of late sequelae deserves particular attention. SBL is more common than PBL; this is a disseminated lymphoma with concomitant involvement of the skeleton. We review the clinical, imaging and pathologic features of bone lymphomas; and discuss therapeutic modalities as well as prognosis of these lymphomas in the era of immunochemotherapy.

Belated Diagnosis of a Primary Bone Lymphoma of the Elbow: A Rare Case and Review of the Literature

Primary non-Hodgkin bone lymphoma (PBL) is a rare disease that accounts for <2% of all lymphomas in adults. PBL can be monostotic or polyostotic, mainly causing destructive and lytic bone lesions frequently located in the femur, humerus, and pelvis. PBL is rarely considered a differential diagnosis of the osteolytic tumor. In addition, PBL is not uncommonly diagnosed with delay because patients do not experience symptoms nor show objective abnormalities in the early stage of disease. Here, we reported a 60-year-old woman with a PBL of the elbow.

Primary Cranial Vault Non-Hodgkin's Lymphoma Mimicking Meningioma With Positive Angiography

Primary non-Hodgkin’s lymphoma of the bone remains an uncommon presentation of non-Hodgkin’s lymphoma. Primary lymphoma of the cranial vault is exceptionally rare. Here, we present a 62-year-old immunocompetent male presenting with the rapid growth of a left parietal scalp lesion and new-onset seizure. In addition to his imaging, which showed an extracranial, cranial, and intracranial mass with bony destruction, sagittal sinus involvement, and parenchymal invasion, his diagnostic angiogram demonstrated extensive vascular supply from both the right and left external carotid branches. Intraoperatively, we confirmed a frank invasion of the posterior sagittal sinus. After subtotal resection followed by R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone therapy, the patient continues to be disease-free at the 10-month follow-up. We report here a case of primary cranial vault lymphoma that very closely mimicked meningioma in many ways, with positive angiography and intraoperatively confirmed venous sinus invasion.

The use of Deauville 5-point score could reduce the risk of false-positive fluorodeoxyglucose-positron emission tomography in the posttherapy evaluation of patients with primary bone lymphomas

Primary bone lymphoma (PBL) is a rare disease. Little is reported about response evaluation procedures in these patients. Our aim was to evaluate response to therapy according to fluorodeoxyglucose-positron emission tomography (FDG-PET) results, and in particular to test the Deauville 5-point scale as compared to the visual evaluation of FDG-PET scans in PBL. In this single-center study, we diagnosed 31 consecutive patients with PBL, of which 24 were evaluated with end-of-treatment FDG-PET. Patients' ages ranged from 19 to 82 years. Six patients were treated with chemotherapy, 24 with chemotherapy and radiotherapy, and one patient with radiotherapy alone. Six patients were affected by a pathological fracture. Four patients died within the range of 3 to 36 months after diagnosis. The average follow-up of the remaining patients was 70 (24–173) months. Overall survival was 87% at 5 years. The only positive prognostic factor was complete remission after chemotherapy. According to visual criteria, end-of-treatment FDG-PET was evaluated in 24 patients and it was positive in 11 (46%) and negative in 13 patients. We organized a retrospective central-blinded revision of end-of-therapy FDG-PET scans using the 5-point Deauville Score (DS). We reviewed 17 out of 24 patients and obtained the following results: at the end of therapy, 12 patients with DS score 2, three patients with DS score 3, one patient with DS score 4, and none with DS score 5. Considering that all the 24 patients achieved complete remission after treatment, visual interpretation produced 11/24 false-positive results, and DS interpretation produced 1/17 false-positive results, thus significantly reducing the number of false positives. In PBL, the final evaluation at the end of therapy with FDG-PET should be evaluated using Deauville 5-point scale in order to significantly reduce the risk of false-positive scans.

Diffuse B Cell Non-Hodgkin's Lymphoma Presenting Atypically as Periprosthetic Joint Infection in a Total Hip Replacement

The occurrence of extranodal primary B cell non-Hodgkin's lymphoma is rare. Total hip replacement is one of the most common orthopaedic procedures performed. There has been an increased incidence of primary lymphomas involving periprosthetic sites. Chronic inflammation due to metal debris arising from the prosthetic implants has been evidenced as one of the causes for the development of soft tissue lymphomas albeit rarely. We describe a case report of a 77-year-old patient who had underwent a cemented total hip replacement in the past who further developed large B cell primary non-Hodgkin's lymphoma. She presented initially with signs and symptoms highly suggestive of underlying periprosthetic infection. The radiological imaging was also indicative of periprosthetic infection. The diagnosis was eventually confirmed after an open biopsy. This case underlines the importance of considering and including soft tissue malignancy in the differential diagnosis of suspected chronic periprosthetic infection.

Modern radiation therapy for extranodal lymphomas: field and dose guidelines from the International Lymphoma Radiation Oncology Group

Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

Primary sternum diffuse large B-cell lymphoma: A case report and review of the literature

Primary bone lymphoma (PBL) is a rare disease, accounting for >1% of all cases of malignant lymphoma. Diffuse large B-cell lymphoma (DLBCL) is the most common histological type of PBL. The present study reported the case of a 68-year-old male with primary bone DLBCL, originally occurred in the sternum, which is a rare form of presentation. Computed tomography (CT), magnetic resonance imaging and bone emission CT were performed, followed by immunohistochemical analysis of a biopsy specimen, and the results were used to establish the diagnosis. At the time of diagnosis, no osseous involvement was observed. The clinical, radiological and histological features of PBL can mimic other medical conditions, thereby making the diagnosis difficult, and frequently leading to delays in treatment. The present study investigated the clinical features, management and prognosis of PBL, and reviewed previous relevant cases.

Socioeconomic and demographic factors contributing to outcomes in patients with primary lymphoma of bone

Background

Primary lymphoma of bone (PLB) is a rare disease, comprising a malignant lymphoid infiltrate of bone. The goal of this study was to identify socioeconomic, demographic, and anatomic factors as prognostic indicators of survival for this disease using the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

The SEER database was used to identify a study population of 692 patients diagnosed with PLB in the United States from 1989 to 2003. Survival was analyzed using the Kaplan–Meier method, with effects of potential prognostic factors on survival analyzed using the log-rank test. Multivariable analysis was performed by Cox proportional hazards regression.

Results

The overall 5-year survival rate was 49.6%, with a 10-year survival rate of 30.2%. Median overall survival was 4.9 years (95% CI: 3.9, 6.1). In multivariable analysis, age (p<0.0001), marital status (p=0.006), and appendicular vs. axial tumor location (p=0.004) were found to be independent predictors of survival.

Conclusions

This population-based study of PLB identified age, marital status, and tumor location as independent indicators of prognosis. This finding supports the clinical suspicion that an appendicular tumor location confers a better prognosis than an axial tumor location.

Primary diffuse large B-cell lymphoma of the bone: bendamustine and rituximab are able to overcome resistant disease

Primary bone lymphoma (PBL) is a rare disease for which specific therapeutic guidelines have not yet been established. Due to common appearance in the elderly and recurring relapses, new treatments are required. We report the case of multiple relapsed aggressive PBL effectively treated using Bendamustine and Rituximab. A 78-year-old male patient presented with a painful mass in the left arm. Computed tomography (CT) showed a pathological tissue in the humerus diaphysis infiltrating the muscle, confirmed by positron emission tomography (PET) scan. Indeed, PET excluded pathological local lymph node involvement. Biopsy of the humerus revealed the presence of diffuse large B cell lymphoma. Recommended treatments for PBL were used, but relapses after an initial complete response occurred. Following the positive experience of Vacirca et al. the patient underwent Bendamustin 90 mg/mq gg1-2 q28 plus Rituximab 375 mg/mq q28 (BR). Herein we report the first experience of BR combination in PBL and it proved to be an efficacious and safe salvage therapy in relapsed/refractory PBL.

Incidental pedal manifestation of primary bone lymphoma: a case report

Primary lymphoma of bone (PLB) is an uncommon entity and is extremely rare in the foot and ankle. In this case, PLB was identified from the bone specimen after a bunionectomy of the first and fifth metatarsals. The diagnosis was confirmed with pathologic analysis, genetic karyotyping, positron emission and computed tomography scans, and fluorescence in situ hybridization (FISH). We felt that reporting this case was essential due to the rarity of its pedal occurrence and the lack of preoperative signs or symptoms.

Results of a Prospective Study of High-Dose or Conventional Anthracycline-Cyclophosphamide Regimen Plus Radiotherapy for Localized Adult Non-Hodgkin's Primary Bone Lymphoma

Background. Primary bone lymphoma (PBL) is a rare entity that has only been reviewed in one prospective and small retrospective studies, from which it is difficult to establish treatment guidelines. We prospectively evaluated high-dose or conventional anthracycline-cyclophosphamide dose and radiotherapy for PBL. Patients and Methods. The GOELAMS prospective multicenter study (1986-1998) enrolled adults with localized high-grade PBL according to age and performance status (PS). Patients <60 years received a high-dose CHOP regimen (VCAP) and those ≥60 years a conventional anthracycline-cyclophosphamide regimen (VCEP-bleomycin); all received intrathecal chemotherapy and local radiotherapy. Results. Among the 26 patients included (VCAP: 19; VCEP-bleomycin: 7), 39% had poor PS ≥2. With a median follow-up of 8 years, overall survival, event-free survival, and relapse-free survival were 64%, 62%, and 65%, respectively, with no significant difference between treatment groups. Poor PS was significantly associated with shorter OS and EFS. Conclusions. Our results confirm the efficacy of our age-based therapeutic strategy. High-doses anthracycline-cyclophosphamide did not improve the outcome. VCEP-bleomycin is effective and well tolerated for old patients. The intensification must be considered for patients with PS ≥2, a poor prognostic factor.

Primary bone lymphoma of the left radius: a case report and related literature review

Primary bone lymphoma (PBL) is a rare but distinct clinicopathological disease. Because it is not common, the optimal treatment strategy has not been established. Here, we present a patient with PBL of the left radius and review the related literature. We focus on the standard treatment for PBL. Many aspects such as rehabilitation, local control and overall survival need to be considered. Studies on this disease should be carried out to clarify the optimal treatment in the future.

Impact of Rituximab and Radiotherapy on Outcome of Patients With Aggressive B-Cell Lymphoma and Skeletal Involvement

Purpose

To study clinical presentation, outcome, and the role of radiotherapy in patients with aggressive B-cell lymphoma and skeletal involvement treated with and without rituximab.

Patients and Methods

Outcome of patients with skeletal involvement was analyzed in a retrospective study of nine consecutive prospective trials of the German High-Grade Non-Hodgkin lymphoma Study Group.

Results

Of 3,840 patients, 292 (7.6%) had skeletal involvement. In the MabThera International Trial (MInT) for young good-prognosis patients and the Rituximab With CHOP Over 60 Years (RICOVER-60) study for elderly patients, the randomized addition of rituximab improved event-free survival (EFS; hazard ratio for MInT [HRMInT] = 0.4, P > 001; hazard ratio for RICOVER-60 [HRRICOVER-60] = 0.6, P > .001) and overall survival (OS; HRMInT = 0.4, P < .001; HRRICOVER-60 = 0.7, P = .002) in patients without skeletal involvement, but failed to improve the outcome of patients with skeletal involvement (EFS: HRMInT = 1.4, P = .444; HRRICOVER-60 = 0.8, P = .449; OS: HRMInT = 0.6, P = .449; HRRICOVER-60 = 1.0, P = .935). Skeletal involvement was associated with a worse outcome after cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) plus rituximab (HREFS = 1.5, P = .048; HROS = 1.1; P = .828), but not after CHOP without rituximab (HREFS = 0.8, P = .181; HROS = 0.7, P = .083). In contrast to rituximab, additive radiotherapy to sites of skeletal involvement was associated with a decreased risk (HREFS = 0.3, P = .001; HROS = 0.5; P = .111).

Conclusion

Rituximab failed to improve the outcome of patients with diffuse large B-cell lymphoma with skeletal involvement, although our data suggest a beneficial effect of radiotherapy to sites of skeletal involvement. Whether radiotherapy to sites of skeletal involvement can be spared in cases with a negative positron emission tomography after immunochemotherapy should be addressed in appropriately designed prospective trials.

Primary lymphoma of bone: outcome and role of surgery

PURPOSE

Primary bone lymphoma is a rare disease. Little is reported about surgical procedures in these patients. We evaluated a single-centre consecutive series of 21 patients for results, prognostic factors and surgical treatment.

METHODS

Patient ages ranged from 19 to 82 years. The most frequently affected site was the spine (six cases), followed by the ileum, femur and mandible (three cases each). Four patients were treated with chemotherapy and 17 with chemotherapy and radiation therapy. Six patients were affected by a pathological fracture. Surgery was performed in four patients (19%), in two cases before chemotherapy, in one case during chemotherapy and in one case after chemotherapy and radiotherapy. Five patients died within the range of three to 36 months after diagnosis. Average follow-up of the remaining patients was 62.8 (19-145) months.

RESULTS

Overall survival was 74.2% at five years. The only positive prognostic factor was complete remission after chemotherapy. A trend for better survival was present for International Prognostic Index (IPI) score (P = 0.051), under 40 years of age (P = 0.10) and abnormal lactate dehydrogenase (LDH) values (P = 0.10), but it did not reach statistical significance.

CONCLUSIONS

Surgical treatment should be aimed at restoring function and eliminating pain while minimising delays in the chemotherapy schedule. When feasible, postponing surgery until after chemotherapy is advisable.

Malignant lymphoma of bone: a review of 119 patients

BACKGROUND

Lymphoma of bone is uncommon. As a result of this, many aspects of primary lymphoma of bone (PLB) are controversial: the definition, treatment strategies, response criteria, and prognostic factors.

QUESTIONS/PURPOSES

We sought to determine the following in an analysis from a single center over a four-decade period: (1) 5-year disease-free survival of patients with PLB as well as those with systemic lymphoma with bone involvement; and (2) whether prognostic factors (sex, site of tumor, age) were associated with 5-year survival.

METHODS

A total of 119 patients with lymphoma involving the musculoskeletal system were retrospectively evaluated. Among these, 94 patients who had a minimum followup of 6 months (mean, 67 months; range, 6 months to 34 years) were further analyzed for the skeletal site of involvement, the orthopaedic intervention(s) needed, and survival. The overall median age was 45 years (range, 7-87 years). The female-to-male ratio was 1:1.53. There were 70 (65 unifocal, five multifocal) patients with PLB. The femur was the most frequent site involved. Appendicular skeleton involvement was substantially higher in patients with PLB. Thirty-four (36%) patients had at least one surgical intervention. Fourteen patients (41%) needed more than one major surgical intervention.

RESULTS

The disease-free 5-year survival for patients with PLB was 81% and for the patients with systemic lymphoma with bone involvement, it was 44%. The disease-free 5-year survival of the patients with PLB younger than 60 years old and 60 years old or older was 90% and 62%, respectively. Age was the only prognostic factor on survival of patients with PLB.

CONCLUSIONS

Orthopaedic intervention was usually needed for pathologic fractures, avascular necrosis, spinal cord compression, or for the lesions of the weightbearing bones compromising stability or joint motion. The potential for long-term survival suggests the use of implants and techniques that have the best chance of long-term success.

Clinical outcomes of treatment for spinal cord compression due to primary non-Hodgkin lymphoma

BACKGROUND CONTEXT

Primary non-Hodgkin lymphoma of the spine (PNHLS) with spinal cord compression is an extremely rare disease in clinical practice. The optimal treatment options for this disease have been controversial and pose a challenge for the clinicians.

PURPOSE

To provide some useful insight into the treatments, outcomes, and prognostic factors of PNHLS.

STUDY DESIGN

Retrospective analysis.

PATIENT SAMPLE

The authors collected 40 patients' data with primary non-Hodgkin lymphoma at the mobile spine, and these patients presented with spinal cord compression as a first symptom between 1998 and 2010.

OUTCOME MEASURES

The posttreatment neurologic status, general status, local recurrence, and survival were noted according to the telephone calls, letters, or follow-up visits in the outpatient department.

METHODS

Multidisciplinary treatments, including surgical intervention, chemotherapy, and radiotherapy, were performed in this series. Follow-ups regarding treatment outcomes, local recurrence, and survival rates were carried out and analyzed. The prognostic factors including age, neurologic status, general status, vertebrae involvement, and treatment outcomes were determined.

RESULTS

The median age of the patients was 52 years (range, 13-79 years). After treatments, 30 patients (75%) reached a complete remission (CR). The 5-year overall survival (OS) of all patients was 72.9%. Patients who were younger than 60 years, with single vertebra involvement, or had CR after treatment had higher 5-year OS (p<.05). In multivariate analysis, CR after treatment and involvement of a single vertebra were identified as favorable prognostic factors for OS.

CONCLUSIONS

Patients with PNHLS with neurologic compression had distinct clinical features. Regarding treatment, the authors emphasized the importance of multidisciplinary management and the optimal operating juncture. Patients with excellent response to the treatment and single vertebra involvement had better survival.

Primary bone lymphoma

Primary bone lymphoma is a distinct clinical entity that accounts for 5% of extra-nodal lymphoma. Most patients have diffuse large B-cell lymphoma and present with bone pain, a mass or both. The involvement could be in a single focus or disseminated. There are no prospective clinical studies in this disease. Patients have been treated with radiotherapy, chemotherapy or a combination. There is a trend towards improved outcome with combined modality treatment and further improvement with the addition of rituximab. Assessment of response may be difficult with current imaging techniques. The prognosis of primary bone lymphoma is generally good. Here, the current evidence for the optimal treatment of primary bone lymphoma is reviewed and questions for future investigation are addressed.

Primary lymphoma of the cranial vault: case report and a systematic review of the literature

BACKGROUND

Bone involvement is a common finding in many types of lymphoma. Cranial vault involvement is extremely rare, and the majority of patients are found at staging to have concurrent disease in lymph nodes. Thirty-eight cases of primary lymphoma of the cranial vault have been reported to date.

METHODS

This article presents a rare case of primary cranial vault lymphoma and conducts a systematic review of the current literature. A total of 36 articles comprising 38 cases were included for analysis. The relevant demographic, clinical, and imaging characteristics, as well as the treatment and outcomes of this unique disease presentation were studied.

RESULTS

The average patient age was 60 years. There was no significant difference in patient gender. The predominant patient complaint was a subcutaneous scalp mass. Of the patients, 11.7% were immunocompromised. CT scans showed signs of osteolysis in 74% of lesions and hyperostosis in 5%, and the cranial vault was observed as normal in 18% of cases. MRI was performed in 23 cases. There was a wide range of histological subtypes, with a slight predominance of diffuse large B-cell lymphoma. Treatment consisted of surgery alone, surgery followed by radiotherapy, and surgery followed by radiotherapy and chemotherapy. The follow-up periods ranged from 5 months to 6 years, with a median value of 7 months. Sixteen patients were followed up to 12 months; 13 of them were alive at 1 year from diagnosis.

CONCLUSION

Primary cranial vault lymphoma is an extremely rare finding. It should be considered in the differential diagnosis of scalp masses. Although the analysis of outcome of the reported cases is difficult because of the small number of occurrences of this entity and the variability of follow-up, a combination of surgery, radiotherapy, and chemotherapy seems to offer better outcomes.

Early-stage primary bone lymphoma: a retrospective, multicenter Rare Cancer Network (RCN) Study

PURPOSE

Primary bone lymphoma (PBL) represents less than 1% of all malignant lymphomas. In this study, we assessed the disease profile, outcome, and prognostic factors in patients with Stages I and II PBL.

PATIENTS AND METHODS

Thirteen Rare Cancer Network (RCN) institutions enrolled 116 consecutive patients with PBL treated between 1987 and 2008 in this study. Eighty-seven patients underwent chemoradiotherapy (CXRT) without (78) or with (9) surgery, 15 radiotherapy (RT) without (13) or with (2) surgery, and 14 chemotherapy (CXT) without (9) or with (5) surgery. Median RT dose was 40 Gy (range, 4-60). The median number of CXT cycles was six (range, 2-8). Median follow-up was 41 months (range, 6-242).

RESULTS

The overall response rate at the end of treatment was 91% (complete response [CR] 74%, partial response [PR] 17%). Local recurrence or progression was observed in 12 (10%) patients and systemic recurrence in 17 (15%). The 5-year overall survival (OS), lymphoma-specific survival (LSS), and local control (LC) were 76%, 78%, and 92%, respectively. In univariate analyses (log-rank test), favorable prognostic factors for OS and LSS were International Prognostic Index (IPI) score ≤1 (p = 0.009), high-grade histology (p = 0.04), CXRT (p = 0.05), CXT (p = 0.0004), CR (p < 0.0001), and RT dose >40 Gy (p = 0.005). For LC, only CR and Stage I were favorable factors. In multivariate analysis, IPI score, RT dose, CR, and CXT were independently influencing the outcome (OS and LSS). CR was the only predicting factor for LC.

CONCLUSION

This large multicenter retrospective study confirms the good prognosis of early-stage PBL treated with combined CXRT. An adequate dose of RT and complete CXT regime were associated with better outcome.

Recurrent PET FDG Uptake after Sequential Chemotherapy and Radiation Therapy for DLBCL of the Tibia: A Case Report and Review of the Literature

The aim of this paper is to report on the challenges associated with identifying disease recurrence following combined modality therapy (CMT) for primary lymphoma of the tibia in which an intramedullary nail has been placed. A patient with primary bone lymphoma (PBL) was treated with CMT (chemotherapy and radiation therapy). After a complete response, he has been followed for eighteen months by physical exam and radiographic imaging. Despite persistent increased tracer accumulation at the original site, he has no proven recurrence. Literature review showed a small number of retrospective, single institution reviews detailing clinical experience and expected outcome in patients treated with PBL limited to one bony site of disease. PBL presents a treatment challenge, particularly when a weight-bearing long bone is diffusely involved and followup is complicated after placement of stabilizing hardware. Close coordination of the oncology team and diagnostic radiology is required to ensure optimal outcome.