The management of stage IIIA Hodgkin's disease

Second malignancy risk associated with treatment of Hodgkin's lymphoma: meta-analysis of the randomised trials

BACKGROUND

Despite several investigations, second malignancy risks (SMR) following radiotherapy alone (RT), chemotherapy alone (CT) and combined chemoradiotherapy (CRT) for Hodgkin's lymphoma (HL) remain controversial.

PATIENTS AND METHODS

We sought individual patient data from randomised trials comparing RT versus CRT, CT versus CRT, RT versus CT or involved-field (IF) versus extended-field (EF) RT for untreated HL. Overall SMR (including effects of salvage treatment) were compared using Peto's method.

RESULTS

Data for between 53% and 69% of patients were obtained for the four comparisons. (i) RT versus CRT (15 trials, 3343 patients): SMR were lower with CRT than with RT as initial treatment (odds ratio (OR) = 0.78, 95% confidence interval (CI) = 0.62-0.98 and P = 0.03). (ii) CT versus CRT (16 trials, 2861 patients): SMR were marginally higher with CRT than with CT as initial treatment (OR = 1.38, CI 1.00-1.89 and P = 0.05). (iii) IF-RT versus EF-RT (19 trials, 3221 patients): no significant difference in SMR (P = 0.28) although more breast cancers occurred with EF-RT (P = 0.04 and OR = 3.25).

CONCLUSIONS

Administration of CT in addition to RT as initial therapy for HL decreases overall SMR by reducing relapse and need for salvage therapy. Administration of RT additional to CT marginally increases overall SMR in advanced stages. Breast cancer risk (but not SMR in general) was substantially higher after EF-RT. Caution is needed in applying these findings to current therapies.

Chemotherapy, radiotherapy and combined modality for Hodgkin's disease, with emphasis on second cancer risk

BACKGROUND

Second malignancies (SM) are a major late effect of treatment for Hodgkin's disease (HD). Reliable comparisons of SM risk between alternative treatment strategies are lacking.

OBJECTIVES

Radiotherapy (RT), chemotherapy (CT) and combined chemo-radiotherapy (CRT) for newly-diagnosed Hodgkin's disease are compared with respect to SM risk, overall (OS) and progression-free (PFS) survival. Further, involved-field (IF-)RT is compared to extended-field (EF-)RT.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register, PubMed, EMBASE, CancerLit, LILACS, relevant conference proceedings, trials lists and publications.

SELECTION CRITERIA

RCTs accruing 30+ patients and completing accrual before/during 2000, comparing at least two treatment modalities for newly-diagnosed HD.

DATA COLLECTION AND ANALYSIS

Individual patient data were collected and assessed for data quality. Trialists submitted additional information concerning methods and data quality. Peto Odds Ratios (OR) with 95% confidence intervals (CI) were calculated for OS, PFS and SM-free survival. Secondary acute leukemia (AL), non-Hodgkin's lymphoma (NHL) and solid tumours (ST) were also analysed separately.

MAIN RESULTS

37 trials (9312 patients) were analysed: 15 (3343) for RT vs. CRT, 16 (2861) for CT vs. CRT, 3 (415) for RT vs. CT and 10 (3221) for IF-RT vs. EF-RT.CRT was superior to RT in terms of OS (OR=0.76, CI=0.66 to 0.89, p=0.0004), PFS (OR=0.49, CI=0.43 to 0.56, p<0.0001) and SM (OR=0.78. CI=0.62 to 0.98, p=0.03). The superiority of CRT also applied to early and advanced stages (mainly IIIA) separately. Excess SM with RT is due mainly to ST and is apparently caused by greater need for salvage therapy after RT.CRT was superior to CT in terms of PFS (OR=77, CI 0.68 to 0.77, p<0.0001). OS was better with CRT for early stages only (OR=0.62, CI 0.44 to 0.88, p=0.006). SM risk was higher with CRT (OR=1.38, CI 1.00 to 1.89, p=0.05), although not significant for early stages alone. This effect, also seen in AL and ST separately, was due directly to first-line treatment. Data were insufficient to compare RT to CT.EF-RT was superior to IF-RT (each additional to CT in most trials) in terms of PFS (OR=81, CI 0.68 to 0.95, p=0.009) but not OS. No significant difference in SM was observed.

AUTHORS' CONCLUSIONS

CRT seems to be optimal for most early stage (I-II) HD patients. For advanced stages (III-IV), CRT better prevents progression/relapse but CT alone seems to cause less SM. RT alone gives a higher overall SM risk than CRT due to increased need for salvage therapy. Reduced SM risk after IF-RT instead of EF-RT could not be demonstrated. Due to the large number of studies excluded because no IPD were received, to the inclusion of many outdated treatments and to the limited amount of long-term data, one must be cautious in applying these results to current therapies.

Chemotherapy of Hodgkin's disease

An overall perspective of chemotherapy for Hodgkin's disease has been presented with particular emphasis on the treatment options to be considered at each stage of the disease. In 1950, M. Vera Peters ended her paper on the 'radiological' treatment of Hodgkin's disease thus: 'In the light of present knowledge the diagnosis of Hodgkin's disease should not be regarded with despair and the patient treated as incurable.... If a single ray of hope emerges from this analysis, the treatment of the individual concerned is a challenge to the combined efforts of the radiotherapist, the physician and the surgeon' (Peters, 1950). Over the ensuing 40 years, substantial progress has been made, but any further improvement must begin with an increase in the proportion of patients for whom complete remission is achieved. Prospective comparisons of hybrid regimens against standard chemotherapy are in progress and the results of these trials will hopefully answer the question as to which is the optimal regimen in the primary treatment of advanced Hodgkin's disease. The advent of growth factors may allow for an increase in dose intensity, possibly improving the results further. The role of very intensive therapy with autologous bone marrow support remains to be defined and is currently being evaluated in different trial settings. Meanwhile, the quest for alternative, less toxic compounds goes on. The challenge continues.

Treatment of patients with "minimal" stage IIIA Hodgkin's disease

Treatment recommendations for patients with upper abdominal Stage IIIA Hodgkin's (III1A) disease have varied widely. The current study reports on a combined institutional retrospective review of 85 patients with surgically staged III1A Hodgkin's disease. Twenty-two patients received combined modality therapy (CMT), 36 patients were treated initially with total nodal irradiation (TNI), and 27 with mantle and para-aortic radiotherapy (MPA). Patients treated with CMT had an actuarial 8-year freedom from relapse (FFR) of 96% as compared to a FFR of 51% in TNI treated patients (p = 0.002), and a FFR of 54% in MPA treated patients (p = 0.004). Of the 11 relapses in MPA treated patients, 7 had a component of their failure in the untreated pelvic or inguinal nodes. The patients treated with CMT had an 8-year actuarial survival of 100% as compared to 79% in TNI treated patients (p = 0.055) and 78% in patients treated with MPA (p = 0.025). Histology and the number of splenic nodules were the most important prognostic variables. Patients with MC/LD histology and greater than or equal to 5 splenic nodules have a high risk of relapse (10/13) when treated with radiation alone (TNI or MPA). We recommend CMT for this group of patients. Patients with NS/LP histology and 1-4 splenic nodules represent a favorable subset of Stage III1A patients. Only 4/21 patients have relapsed and all 21 patients are currently alive without disease regardless of treatment. We currently feel that patients with Stage III1A Hodgkin's disease with NS/LP histology and splenic disease limited to 1-4 nodules are good candidates for MPA as an alternative to TNI or CMT.

Treatment selection for stage IIIA Hodgkin's disease patients

Two treatment policies for the therapy of patients with Stage IIIA Hodgkin's disease are compared. From 1969-1976, 49 newly diagnosed and pathologically staged IIIA patients received total nodal irradiation (TNI) alone (no liver irradiation). Although actuarial survival was 80% at 5 years and 68% at 10 years, actuarial freedom from relapse was only 38% at 5 years. Accordingly, a new treatment policy was instituted in 1976. Patients with either CS IIIA disease, multiple splenic nodules, IIIA with a large mediastinal mass or III2, received combined modality therapy (combination chemotherapy and irradiation). All others received TNI. Thirty-six patients have been treated under the new program. The actuarial survival is 90% at 5 years and the relapse-free survival is 87%, suggesting the superiority of this approach.