Localized primary malignant lymphoma of bone

Small Round Cell Tumors of Bone

Context.—Primary small round cell tumors of the bone are a heterogeneous group of malignant neoplasms presenting predominantly in children and adolescents. They include Ewing sarcoma/peripheral neuroectodermal tumor or Ewing family tumors, lymphoma, mesenchymal chondrosarcoma, and small cell osteosarcoma. Even though they share many morphological similarities, their unique biological and genetic characteristics have provided substantial insights into the pathology of these diverse neoplasms.

Objective.—To provide an overview of the clinical, radiologic, pathologic, and genetic characteristics of these tumors along with a pertinent review of the literature.

Data Sources.—A literature search using PubMed and Ovid MEDLINE was performed, and data were obtained from various articles pertaining to clinicopathologic, biological, and genetic findings in these tumors. Additionally, findings from rare cases have been included from author's subspecialty experience.

Conclusion.—The diagnosis of small round cell tumors can be made accurately by applying clinicopathologic criteria, as well as a panel of immunohistochemical and genetic studies in appropriate cases. Molecular genetic studies may provide further insight into the biology, histogenesis, and prognosis of these tumors.

A clinicopathological retrospective study of 131 patients with primary bone lymphoma: a population-based study of successively treated cohorts from the British Columbia Cancer Agency

BACKGROUND

Primary bone lymphoma (PBL) is a distinct clinicopathological entity. Although PBL has been reviewed in several small studies, few reflect recent improvements in primary treatment.

METHODS

We used the British Columbia Cancer Agency Lymphoid Cancer Database to identify all patients with PBL (1983-2005). All were staged in a uniform manner and treated with era-specific protocols.

RESULTS

We identified 131 patients with a median age of 63 years (18-87). One third had disease in long bones and another one third had disease in the spine, of which half presented with spinal cord compression. Patients with diffuse large-cell lymphoma (DLCL) (n=103, 79%) had 5- and 10-year overall survivals (OS) of 62% and 41%, respectively. Multivariate analysis identified three prognostic groups: age<60 with International Prognostic Index (IPI) 1-3 (n=43), age>or=60 with IPI 0-3 (n=23) and age>or=60 with IPI 4-5 (n=33), with markedly different 5-year OS of 90%, 61% and 25%, respectively (P<0.0001). Neither primary site nor pathological fracture at presentation had an impact on OS. The 3-year progression-free survival in patients who received rituximab plus combination chemotherapy with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOPR) chemotherapy was 88% compared with 52% in those who received CHOP-like chemotherapy without rituximab (P=0.005). The 10-year OS for those with advanced-stage disease who received irradiation plus chemotherapy was 25% versus 56% for those who received chemotherapy alone (P=0.025). Patients received irradiation if spinal cord compression was present or residual disease at the end of chemotherapy was thought to require it.

CONCLUSIONS

PBL is usually of DLCL type and has an improved outcome with CHOPR. Younger patients with good IPI score have a favorable prognosis.

Primary bone lymphoma: treatment results and prognostic factors with long-term follow-up of 82 patients

BACKGROUND

To the authors' knowledge, there is limited information on the preferred treatment and long-term prognosis of primary bone lymphomas (PBLs). All PBL cases treated at the study center between 1963 and 2003 were analyzed to determine patient, disease, and treatment factors that could affect outcome measured by overall survival (OS), cause-specific survival (CSS), and freedom-from-treatment failure (FFTF).

METHODS

A total of 101 patients with PBL diagnosed at the study institution were identified. Nineteen patients were excluded because they transferred their treatment or follow-up to another center. Disease control, survival, and prognostic factors were analyzed for all 82 remaining patients.

RESULTS

The median age of the patients was 48 years (range, 11-83 years). Approximately 80% presented with diffuse large-cell lymphoma (DLCL), and 81% presented with Ann Arbor Stage I or II disease. Approximately 57% were treated with combined modality therapy, 14% were treated with radiation therapy alone, and 30% were treated with chemotherapy alone. The median follow-up was 67 months (range, 2-280 months). The 5-year OS, CSS, and FFTF were 88%, 96%, and 81%, respectively. The 5-year OS for patients treated with combined modality versus single-modality therapy was 95% versus 78% (P = .013), and the 5-year FFTF for patients treated with combined modality versus single-modality therapy was 90% versus 67% (P = .025). The 5-year CSS for patients treated with combined modality versus single-modality therapy was 95% versus 83% (P = .065). Using a Cox regression for multivariate analysis, age < 40 years and use of combined modality therapy were found to be favorable prognostic factors for OS, CSS, and FFTF.

CONCLUSIONS

To the authors' knowledge, the current study is the largest series of patients with PBL treated with modern curative modalities. The data demonstrate that primary lymphoma involving the bone has an excellent prognosis. Patients with PBL treated with combined modality versus single modality therapy were found to have a superior outcome, with a significantly better survival.

Non-Hodgkin's lymphoma presenting as multiple bone lesions and hypercalcemia

We report a rare case of a patient with non-Hodgkin's lymphoma who developed multiple bone lesions and hypercalcemia. A 50-year-old woman complained of drowsiness and multiple bone pain on admission. Radiographic examination revealed multiple bone fractures and osteolytic lesions. She was diagnosed with diffuse large B cell lymphoma by biopsy of an inguinal lymph node. Elevation of parathyroid hormone-related protein (PTHrP) and hypercalcemia were confirmed pretreatment, and those serum levels decreased during chemotherapy for lymphoma. However, the disease was resistant to chemotherapy combined with rituximab. These findings suggest that hypercalcemia is associated with PTHrP and the prognosis of patients with bone lymphoma in advanced stage is poor, although it is thought to be a relatively favorable prognosis in localized primary lymphoma of bone.

Primary bone lymphoma

Primary bone lymphoma is a rare condition which represents a low percentage of both the malignant primary bone tumours and the non-Hodgkin extranodal lymphoma. This explains the lack of publications, lines of investigations, and specific diagnostic and treatment protocols. In the following article we will carry out a revision of the existing literature on this rare subject, using as argument a clinical case of left femoral location stage IE treated with CHOP chemotherapy and radiotherapy.

De novo CD5-positive diffuse large B-cell lymphoma of the temporal bone presenting with an external auditory canal tumor

We report a 74-year-old woman with primary CD5-positive diffuse large B-cell lymphoma (DLBCL) of the temporal bone. The patient was admitted because of a mass in the left external auditory canal. She was treated with eight courses of CEOP therapy (rituximab was added from the sixth course) followed by radiotherapy of 40 Gy, and complete remission was achieved. The occurrence of malignant lymphoma in the temporal bone, which is an extremely unusual site, may have depended on the peculiarity of CD5-positive DLBCL.

Primary lymphomas of bone

Primary bone lymphoma is rare. The majority of cases are diffuse large B-cell non-Hodgkin's lymphomas. Classification, staging, and treatment are controversial. The relatively small number of cases has led to many case reports and series describing institutional experiences but precludes the use of randomized clinical trials to address the question of optimal management. This article will review clinical and radiologic presentations, diagnostic techniques, and histologic characteristics. Most important, it will present what limited information we do have regarding effective treatment options for this unusual type of lymphoma.

Primary non-hodgkin's lymphoma of the bone: treatment and analysis of prognostic factors for Stage I and Stage II

PURPOSE

Primary non-Hodgkin's lymphomas of the bone (PLB) are very rare diseases accounting for 3%-5% of primary bone tumors. The best treatment for PLB has not been found yet. We report on the experience of the Radiation Oncology Department of Bologna University, Italy, relative to the diagnosis and treatment of this disease.

METHODS AND MATERIAL

Seventy-seven patients with newly diagnosed PLB were treated from June 1983 to October 2001. Fifty-six were male (72.7%) and 21 were female (27.3%); the median age was 41.8 years, with a range of 16-84 years. The majority of patients had B-cell high-grade histology. The median follow-up was 149 months. Forty-four patients had a solitary bone lesion (Stage I); and in 33 patients, the tumor was spread to locoregional lymphatic area (Stage II). All patients were treated with radiotherapy (RT) with a median dose of 40 Gy (range, 36-54 Gy), and 67 received an additional anthracycline-based regimen of chemotherapy (combined modality therapy [CMT]).

RESULTS

After therapy 73 of 77 patients (94.8%) reached a complete remission. At a median time of 23 months, 14 of 77 patients (18.2%) had a disease relapse. Four of them were treated with RT alone (in these cases tumor lesions were <3 cm and located at sites different from mandible); 10 patients were treated with combined RT and CMT. Actuarial disease-free survival (DFS) and overall survival (OS) at 15 years were, respectively, 76.6% and 88.3%. No local failures were seen. Prognostic factors such as age, sex, stage, and bulky lesions were analyzed. Age (<40 vs. >40 years) was the only significant factor for DFS (85.3% vs. 66.6%, p = 0.03). Bulky lesions apparently did not affect OS (90.9% vs. 72.7%). However, the difference has no statistical significance (p = 0.05). Acute and late toxicity related to the treatment was moderate.

CONCLUSIONS

In PLB the CMT seems to produce a better outcome than RT alone; that still remains the best treatment for local disease control. Radiation therapy alone should be reserved for mandibular tumors, which are usually very small and earlier diagnosed.

Oncologic outcomes of primary lymphoma of bone in adults

A retrospective analysis of adult patients who had lymphomatous involvement of bone was done to evaluate the prognostic factors and the oncologic outcome. Between 1984 and 1994, 28 patients (nine women and 19 men) were diagnosed with lymphoma of bone. The median age was 45 years (range, 23-76 years). The median followup was 40.3 months (range, 0.5 months-15.8 years). Eighteen patients (64%) were classified as having Stage IE disease, two patients (36%) were classified as having stage II disease, and eight patients were classified as having Stage IV disease. Twenty-one of the lesions were classified as diffuse large B cell with multilobulated nuclei. Two patients had local recurrence. Three patients had osteonecrosis develop at the site of their radiation therapy. The 5-year Kaplan-Meier survival estimate was 57.8% (95% confidence interval range, 40-33 82.8). Statistically improved survival was seen in patients younger than 40 years and those patients with diffuse large B cell with multilobulated nuclei. Patients with primary lymphoma of bone did not have a statistically improved survival compared with patients with systemic disease. The results of the current study suggest that age at diagnosis and histologic subtypes are important prognostic factors; however, the diagnosis of primary lymphoma of bone does not confer improved prognosis.

Excellent long-term survival in patients with early-stage primary bone lymphoma treated with doxorubicin-based chemotherapy and local radiotherapy

Primary bone lymphoma accounts for less than 5% of primary extranodal presentations, and the majority are of the diffuse, large cell, B-cell type. The study presents the authors' 21 years of experience (1979-2000) in ten patients with early stage (IE-IIE) primary bone lymphoma. All patients were treated with doxorubicin-based chemotherapy. Seven received consolidation radiotherapy to an area encompassing the primary tumor with generous margins, including the adjacent soft tissues, and in two stage IIE patients also to the regional lymph nodes. Mean total dose was 3989 cGy. Nine patients are alive with no evidence of recurrent disease. There are no severe late side effects, and only one patient died due to therapy-resistant small cell lung cancer (second primary), while in complete remission from his primary lymphoma. Albeit retrospective in nature with a small patient accrual, this study demonstrates that primary bone lymphoma is a curable disease following aggressive doxorubicin-based chemotherapy. The exact rule of radiation therapy is yet to be determined.

Primary lymphoma of bone--survival and prognosis

BACKGROUND

Primary lymphoma of bone is a rare disease. There is yet no systematical evaluation of primary lymphoma of bone in Korea. Here we report our experience of sixteen cases with primary lymphoma of bone focusing on the survival.

METHODS

Sixteen cases, collected for 13 years, were evaluated on the clinical presentation, histologic subtype, stage and treatment outcomes of the primary bone lymphoma.

RESULTS

The most common presenting complaint was bone pain. Malignant lymphoma of bone involved a wide variety of sites, the most prevalent site of which in this study was the spine. Most of the cases were in the diffuse large B-cell category. The clinical stage of lymphoma was IEA in two cases, IIEA in three cases, IVEA in five cases and IVEB in three cases. All treated cases received systemic chemotherapy and ten cases among them were treated with combined modality therapy. Median overall survival was not reached after median follow-up period of 28 months and five-year overall survival rate was 54%.

CONCLUSION

More promising therapeutic strategies are needed for survival improvement on more accumulated cases.

Non-Hodgkin's lymphoma arising in bone in children and adolescents is associated with an excellent outcome: a Children's Cancer Group report

PURPOSE

Non-Hodgkin's lymphoma (NHL) arising in bone is a heterogeneous histologic type of NHL that includes large-cell lymphoma, lymphoblastic lymphoma, and small noncleaved-cell lymphoma. NHL arising in bone is well recognized in adults but is less well characterized and infrequent in children and adolescents.

PATIENTS AND METHODS

We performed a retrospective review of Children's Cancer Group (CCG) studies treating children and adolescents with NHL over a 20-year period (CCG-551, CCG-501, CCG-502, CCG-503, CCG-552, CCG-5911, and CCG-5941) and determined the response and event-free survival (EFS) rates in 31 patients with NHL arising in bone.

RESULTS

The patients ranged in age from 3 to 17 years (median, 11 years; mean, 11 years), and 64.5% were male. All 31 (100%) patients achieved complete response. For 31 patients with NHL arising in bone, the product-limit estimated 5-year EFS was 83.8% +/- 6.7%. EFS in 17 patients with localized disease (Murphy stages I and II) was 94.1% +/- 5.7%, and EFS in 14 patients with disseminated disease (Murphy stage III) was 70.7% +/- 12.4% (log-rank P =.10). EFS in 17 patients treated with chemotherapy and radiation was 70.1% +/- 11.2%, and EFS in 14 patients treated with chemotherapy without radiation was 100% (P =.03). EFS in 26 patients with histology-directed treatment (LSA2-L2 or ADCOMP for lymphoblastic, other therapy for nonlymphoblastic) was 92.2% +/- 5.3%, and in five patients with nonhistology-directed treatment it was 40.0% +/- 21.9% (P <.001).

CONCLUSION

NHL arising in bone is a heterogeneous type of NHL that makes up approximately 2.0% of NHL in children and adolescents on CCG studies. Response and survival in this young age group seem superb, with histology-directed treatment protocols without radiation in both localized and disseminated disease.

Staging and management of localized non-Hodgkin's lymphomas: variations among experts in radiation oncology

PURPOSE

To examine the opinions of radiation oncology experts on the management of lymphomas with respect to staging procedures, treatment plan, radiation target volume, and dose prescription. Our aim was to identify the patterns of practice and areas of controversy that may need to be resolved and be amenable to prospective clinical trials.

MATERIALS AND METHODS

Radiation oncology experts in lymphoma management were identified from academic centers in the United States, Europe, and Canada. A sample of individuals with a publication record and/or participation in the design and execution of lymphoma clinical trials (n = 33) were mailed a questionnaire of five case scenarios. The experts were asked to specify their approaches to staging investigations, treatment plan, radiation target volume, and dose prescription for each scenario. Radiation fields were indicated by the respondents on a schematic anatomy diagram on the questionnaire. The response rate to the survey was 82% (27/33).

RESULTS

Staging of lymphomas relied on the use of imaging, because computed tomography of the abdomen and pelvis was recommended in all cases, and computed tomography of the uninvolved thorax was advocated by 70% of respondents. A lymphangiogram and a gallium scan were suggested by, respectively, 26% and 25% of respondents. The overall treatment plan was uniform for the four cases of localized presentations of lymphoma. However, the details of chemotherapy and radiation target volume varied significantly. Variations were observed in recommendations regarding the number of courses of chemotherapy and the extent of radiotherapy. The survey documented significant differences in the recommended radiation therapy (RT) dose (30-50 Gy). The scenario of leptomeningeal relapse in diffuse large B-cell lymphoma documented the most diverse treatment recommendations. These varied from whole-brain radiation alone to systemic and intrathecal chemotherapy, radiation with craniospinal coverage, and high-dose chemotherapy with bone marrow transplantation.

CONCLUSIONS

This survey demonstrated a high degree of consensus regarding the overall management plan of localized lymphomas among the sampled expert radiation oncologists. However, the recommendations regarding the specifics of chemotherapy and RT remain variable. There is clearly no agreement on the most appropriate RT dose and volume. The large variation in the treatment of leptomeningeal relapse of diffuse large B-cell lymphoma suggests that the optimal treatment in this situation is poorly defined, and the clinical outcome with RT, as well as the rationale for decision making, should be examined in more detail.

An immunophenotypic and molecular study of primary large B-cell lymphoma of bone

Primary non-Hodgkin's lymphomas of bone (PNHLB) is a rare form of extranodal lymphoma. Many studies have reported the clinical, radiologic, and histopathologic characteristics of PNHLB; however, their molecular features have not been well studied. In this report, we present the immunophenotypic and molecular characteristics of 20 primary large B-cell lymphoma (PLBCL) of bone from 20 adults. Most demonstrated centroblastic morphology, with the majority exhibiting nuclear multilobation. One case (5%) demonstrated anaplastic features with strong CD30 expression but was ALK-1 negative. BCL-6 expression was seen in 6 of 20 cases, and strong p53 protein expression was seen in 11 of 20 (55%) cases. The majority of cases analyzed (13/18 = 72%) demonstrated a clonal B-cell process by IgH gene rearrangement studies. Of the five cases that did not demonstrate a clonal population, two expressed BCL-6 protein. No cases demonstrated a bcl-2/JH rearrangement, but BCL-2 protein expression was seen in 11 of 20 (55%) cases. In summary, primary lymphoma of bone is largely a non-Hodgkin's lymphoma of large B-cell type. Our studies demonstrate that p53 and BCL-2 expression may play a role in the pathogenesis of PLCBL of bone. In addition, a subset of the cases are of putative germinal center B-cell origin based on the expression of BCL-6 protein and may be genetically distinct from follicle center lymphomas. The results provide evidence for molecular heterogeneity within primary large B-cell lymphomas of bone.

Richter's syndrome following cladribine therapy for chronic lymphocytic leukemia first manifested as pathologic fracture of the femur

Richter's syndrome (RS) refers to the development of aggressive non-Hodgkin's lymphoma (NHL) during the course of chronic lymphocytic leukaemia (CCL). It occurs in approximately 3% of patients with CLL. The isolated form of this complication in bone is extremely rare and, so far, has not been described in a patient treated with cladribine (2-CdA). We report a case of CLL treated successfully with 2-CdA, where isolated diffuse large B-cell lymphoma (LBCL) developed 2 years after the diagnosis of CLL Rai II and one year after the completion of 2-CdA treatment. RS was first manifested as a pathologic fracture of the left femur. The LBCL was clonally distinct from the original CLL cells. The patient was successfully treated with CHOP and radiotherapy and obtained complete response of the LBCL.

Dose-response analysis for radiotherapy delivered to patients with intermediate-grade and large-cell immunoblastic lymphomas that have completely responded to CHOP-based induction chemotherapy

PURPOSE

To test the hypothesis that prechemotherapy tumor size affects the dose of radiation that should be delivered to intermediate-grade and large-cell immunoblastic lymphomas that have completely responded to cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP)-based induction chemotherapy.

METHODS AND MATERIALS

From September 1988 through December 1996, 294 patients with newly diagnosed, Stage I-IV, intermediate-grade or large-cell immunoblastic lymphomas were enrolled on 2 prospective protocols at the M. D. Anderson Cancer Center. Treatment consisted of CHOP-based chemotherapy with or without involved field radiotherapy. One hundred seventy-two patients, with 178 nodal sites and 87 nonbony, extranodal sites of disease achieved a complete response to 2-6 cycles of chemotherapy and underwent involved field radiotherapy. Total radiation doses ranged from 30.0 to 50.4 Gy (mean +/- standard deviation: 39.7 +/- 2.5 Gy) over 22-49 days using a daily fraction size of 1.3-2.3 Gy. Because various fraction sizes were delivered, the linear-quadratic model was used to convert total radiation doses to biologically equivalent doses given at 1.8 Gy per fraction (D1.8). An alpha/beta ratio of 10 Gy was used for the lymphomas, resulting in D1.8 ranging from 29.1 to 50.8 Gy. Regression tree analysis was performed on nodal sites of disease to determine which of the following factors were predictive of local control: age, tumor size, D1.8, total radiation dose, and duration of radiotherapy. Based on the results of the regression tree analysis, Kaplan-Meier analysis was used to determine the probability of local control per site as a function of tumor size and D1.8. Regression tree analysis was also performed on patients with nonbony disease who received D1.8 = 29.1-39.1 Gy to determine if small lymphomas could be locally controlled with relatively low doses of radiation. The log-rank test was used to compare local control curves.

RESULTS

The median length of follow-up among survivors was 63 months. Regression tree analysis of nodal sites identified 3 distinct groups: (a) lymphomas < or = 10 cm and D1.8 = 29.1-39.1 Gy; (b) lymphomas < or = 10 cm and D1.8 = 39.2-50.8 Gy; and (c) lymphomas > 10 cm. For nonbony lymphomas that measured < 3.5 cm, low doses of radiation resulted in excellent local control (5-year rates: 96% vs. 97% for D1.8 = 29.1-39.1 Gy vs. D1.8 = 39.2-50.8 Gy; p = 0.610). For 3.5-10.0 cm lymphomas, higher doses of radiation resulted in better local control (5-year rates: 40% versus 98% for D1.8 = 29.1-39.1 Gy versus D1.8 = 39.2-50.8 Gy, p < 0.0001). A narrow dose range (D1.8 = 39.2-40.7 Gy) was delivered to the 8 lymphomas measuring > 10 cm that completely responded to 6 cycles of chemotherapy, resulting in a 5-year local control rate of only 70%. There was no difference in local control for nodal versus nonbony, extranodal sites of disease.

CONCLUSION

D1.8 ranging from 29.1 to 39.1 Gy yielded excellent local control for nonbony lymphomas measuring < 3.5 cm that had completely responded to a median of 3 cycles of CHOP-based chemotherapy. D1.8 ranging from 39.2 to 50.8 Gy yielded excellent local control for nonbony lymphomas measuring 3.5-10.0 cm that completely responded to either 3 or 6 cycles of chemotherapy. For nonbony lymphomas measuring > 10 cm that completely responded to 6 cycles of chemotherapy, D1.8 ranging from 39.2 to 40.7 Gy yielded suboptimal local control, suggesting that higher doses of radiation are indicated.

Multicentric lymphosarcoma in a dog with multiple-site skeletal involvement

In this report the authors describe an unusual clinical presentation of lymphosarcoma (LSA) in a dog. A 9-year-old, neutered male, Golden Retriever was presented with a primary complaint of sudden onset of tetraparesis. Routine survey radiographs revealed multiple-site bony lesions and the histology revealed a diagnosis of LSA with diffuse skeletal and soft tissue involvement. The dog responded poorly to medical management and was euthanized on day two due to poor prognosis. Malignant LSA of the bone is a rare extranodal clinicopathologic entity and presents both a diagnostic and therapeutic hurdle. Reports of this kind are sparse and currently no optimal treatment for this entity has been determined.

Long-term results of combined modality therapy in primary bone lymphomas

PURPOSE

To report the Massachusetts General Hospital experience in the management of patients with primary bone lymphoma (PBL) treated with combined modality therapy (CMT).

METHODS AND MATERIALS

Records from 37 eligible patients were reviewed. Two patients were treated with complete resection of the tumor, while 35 patients underwent radiation therapy with a median total dose of 54 Gy (range 38.35-66.5). All patients received combination chemotherapy, which contained doxorubicin in 33 cases. We compared the current data with our previous experience in patients treated with local measures only.

RESULTS

Actuarial disease-free survival (DFS) at 5 and 10 years is 78% and 73%, respectively, while overall survival (OS) is 91% and 87%, respectively. No local failures were seen. Pathologic fracture at presentation influenced DFS (p = 0.005) and OS (p = 0.017) adversely. OS was compromised in patients older than 60 years (p = 0.059) and DFS in patients with pelvic primaries (p = 0.015). CMT was associated with improved DFS (p = 0.0008) and OS p = 0.0001) compared to our historical controls. Ten patients (27%) developed complications requiring orthopedic procedures following completion of therapy at a median of 25.5 months (range 4-228).

CONCLUSION

Patients with PBL have a favorable outcome with CMT, which appears superior to radiation therapy alone. Late complications can be seen, especially in weight-bearing bones.

Osteolymphoma (primary bone lymphoma): an Australian review of 70 cases. Australasian Radiation Oncology Lymphoma Group (AROLG)

BACKGROUND

To examine prognostic factors, treatment outcomes and design future studies for Osteolymphoma (OL)--also known as primary bone lymphoma.

METHODS

Between 1979 and 1993, 70 patients with OL were treated in nine Australian centres. The effect of patient-, tumour-, and treatment-related factors on local control, distant disease-free survival and overall survival were assessed by multivariate analysis.

RESULTS

Most patients (94%) received radiotherapy (RT) (median dose 40 Gy) and 56% received chemotherapy. Multifocal disease was present in 20% of patients. The five year rates of overall survival and local control were 59% and 82%. Although there was a trend towards better results with the addition of chemotherapy, on multivariate analysis, there were no factors identified which appeared to impact upon overall and disease-free survival. Among the distant recurrences, there was a high proportion in bone (33%). Six patients suffered pathological fractures after treatment.

CONCLUSION

High rates of local control were achieved by RT, but the overall survival remains relatively poor, worse than nodal lymphoma. The natural history of the disease suggests that OL may be a distinct entity, different to nodal lymphomas, so the results of clinical trials in nodal lymphoma may not be relevant to OL. Prospective studies could define the outcome of combined modality therapy and set a benchmark for testing further proposals, as well as improving our knowledge of the clinical features of OL.