The significance of molecular response of follicular lymphoma to central lymphatic irradiation as measured by polymerase chain reaction for t(14;18)(q32;q21)

Treatment strategies in limited stage follicular NHL

Limited stage (I-II) follicular lymphoma is an uncommon entity, since most patients with this disease have generalized adenopathy (stage III) or bone marrow involvement (stage IV). Although patients who present with stage III-IV disease often are considered to be incurable, ~50% of patients with limited disease will enjoy long-term freedom-from progression, usually following treatment with radiation therapy. Relapse among these patients is uncommon after 10 years and exceedingly rare after 15 years. Radiation treatment is generally restricted to the involved nodal region(s) with modest (~5 cm.) extension proximally and distally. Radiation dose is generally 30 Gy, but may be boosted slightly (36 Gy total) in the presence of bulky disease. Randomized clinical trials have been insufficiently powered to define the value of any additional treatment beyond radiation therapy, although single arm studies suggest a benefit to the addition of chemotherapy. There have been no reported experiences with chemo-immunotherapy or radioimmunotherapy. Patients should be monitored during follow up to identify transformation to a more aggressive lymphoma.

Evolving role of radiation therapy for hematologic malignancies

Radiation therapy continues to play a paramount role in the therapy of hematologic malignancies, whether as definitive therapy, as consolidation after chemotherapy, as part of bone marrow transplantation protocols, or in palliation. During the past 2 decades, significant advances in radiation therapy have occurred, including the evolution of involved-field irradiation and the adoption of conformal radiation administration. It is hoped that modern techniques will reduce the long-term sequelae associated with radiation-based treatments.

A prospective randomized study to compare the molecular response rates between central lymphatic irradiation and intensive alternating triple chemotherapy in the treatment of stage I–III follicular lymphoma

PURPOSE

This study was undertaken to compare the molecular response (MR) rates of 2 regimens, central lymphatic irradiation (CLI) and alternating triple therapy (ATT), in the treatment of Stage I-III follicular lymphoma. MR was defined as disappearance of t(14;18) (q32;q21) amplified by polymerase chain reaction (PCR).

PATIENTS AND METHODS

Sixty-five patients with Stage I to III follicular lymphoma were randomized. CLI consisted of the mantle, abdomen, and pelvic radiation fields. ATT alternated among CHOD-Bleo, ESHAP, and NOPP for 12 courses. Bone marrow (BM) and peripheral blood (PB) samples were obtained before treatment for PCR analysis. PCR-positive patients were followed by PCR analysis. The random-effects logistic model was fitted to the data from the posttreatment PCRs. The factors included in the model were treatment arm, type of PCR (BM vs. PB), and time to PCR sample procurement from the date of registration.

RESULTS

At a median follow-up of 71 months, the 5-year relapse-free survival (RFS) rates were 45% and 54% for CLI and ATT, respectively (p = 0.42). The probability of attaining an MR increased with time after registration (p = 0.007), was lower for BM compared with PB (p = 0.012), and was higher for ATT than for CLI (p = 0.020).

CONCLUSION

ATT regimen achieved a higher MR than CLI, although both arms had similar 5-year RFS.

Central lymphatic irradiation for stage I-III follicular lymphoma: report from a single-institutional prospective study

PURPOSE

This study was undertaken to update our experience with follicular lymphoma treated with central lymphatic irradiation (CLI).

METHODS AND MATERIALS

A total of 47 patients were treated with CLI between January 1993 and March 2000 in a prospective manner. CLI consisted of mantle, whole abdomen, and pelvic radiation fields with a 1-month break after each field. Each field was treated to 3000-3060 cGy at 150-180 cGy per fraction followed by a boost dose of 900 cGy to the areas with gross disease. The median age was 52 years (range: 29-73 years). There were 29 males. The diagnoses were as follows: follicular small cleaved-cell lymphoma, 23 patients; follicular mixed-cell lymphoma, 19 patients; follicular large-cell lymphoma, 5 patients. Ann Arbor stages were as follows: I, 5 patients; II, 14 patients; and III, 28 patients. The International Prognostic Index (IPI) categories were as follows: 0, 14 patients; 1, 24 patients; and 2, 9 patients. M. D. Anderson Tumor Score was as follows: 0, 14 patients; 1, 18 patients; 2, 9 patients; 3, 4 patients; 4, 1 patient; and unknown, 1 patient. Two patients had abnormal LDH levels, and 11 patients had beta2M levels >2 mg/dL. Gender, pathology, stage, IPI, Anderson Tumor Score, beta2M, and number of disease sites were examined for significance in freedom from progression (FFP) by univariate analyses.

RESULTS

The median follow-up was 54 months (range: 8-93 months) for the 45 surviving patients. Every patient achieved a complete response, except for 1 patient whose lymphoma progressed to diffuse large-cell lymphoma during treatment. The 5-year overall survival and FFP were 94% and 53%, respectively. No failure has yet been observed beyond 55 months of follow-up with 13 patients at risk. Patterns of failure were as follows: within the radiation field, 10; outside the fields, 4; and both, 2. Of the seven variables investigated, beta2M >2 mg/dL and IPI >1 were the only significant adverse prognostic factors for FFP (p = 0.023 and 0.046, respectively).

CONCLUSIONS

CLI is well tolerated and seems to achieve durable FFP in about half of the patients with Stage I-III follicular lymphoma. Most of the experiences with CLI come from the treatment of Stage III disease and are very similar to our previous experience with combined modality treatment. Whether a plateau in FFP can be maintained beyond 5 years remains to be seen.

Minimal residual disease (MRD) in follicular lymphoma in the era of immunotherapy with rituximab

The t(14;18)-translocation can be detected by PCR analysis in more than 90% of cytogenetically t(14;18)-positive follicular lymphomas (FLs), thus providing an easily accessible marker for molecular disease monitoring. Various technical aspects of the detection of residual lymphoma cells as well as the prognostic and clinical significance of the detection of minimal residual disease (MRD) after radiotherapy, chemotherapy and therapy with the monoclonal antibody rituximab are discussed. Up to now the comparability of the different studies investigating minimal residual disease in follicular lymphoma patients is hampered by the use of a variety of PCR techniques. A more standardized quantitative approach based on the real-time PCR technique will provide a powerful tool for the evaluation and optimization of therapy for each individual patient.

Long-term results with radiotherapy for Stage I-II follicular lymphomas

PURPOSE

To analyze the long-term results with radiotherapy (RT) for early-stage, low-grade follicular lymphomas.

METHODS AND MATERIALS

From 1960 to 1988, 80 patients with Stage I (n = 33) or II (n = 47), World Health Organization Grade 1 (n = 50) or 2 (n = 30) follicular lymphoma were treated with RT. The lymph nodes or spleen were involved in 97% of cases. The maximal tumor sizes ranged from 0.5 to 11.0 cm (median 2.0). The RT fields encompassed only the involved Ann Arbor nodal region (involved-field RT) in 9% of the patients. The fields also included 1-3 adjacent, grossly uninvolved nodal regions (regional RT) in 54% of patients but were smaller than mantle or whole abdominopelvic fields. Mantle or whole abdominopelvic fields encompassing up to 6 grossly uninvolved regions (extended-field RT) were used in the remaining 37% of patients. The total RT doses ranged from 26.2 to 50.0 Gy given in daily 1.0-3.0-Gy fractions.

RESULTS

The follow-up of the surviving patients ranged from 3.5 to 28.7 years (median 19.0). No recurrences were found >17.0 years after RT, with 13 patients free of disease at their last follow-up visit 17.6-25.0 years after treatment. In 58% of cases, death was not from follicular lymphoma. The 15-year local control rate was 100% for 44 lymphomas <3.0 cm treated with only 27.8-30.8 Gy (median 30.0 in 20 fractions). Progression-free survival was affected by the maximal tumor size at the start of RT (15-year rate 49% vs. 29% for lymphomas <3.0 cm vs. > or =3.0 cm, respectively, p = 0.04) and Ann Arbor stage (15-year rate 66% vs. 26% for Stages I and II, respectively, p = 0.006). Ann Arbor stage also affected the cause-specific survival (15-year rate 87% vs. 54% for Stages I and II, respectively, p = 0.01). No significant difference was found in overall survival between those treated with extended-field RT and those treated with involved-field RT or regional RT (15-year rate 49% and 40%, respectively, p = 0.51). The 15-year incidence rate of Grade 3 or greater late complications according to the Subjective, Objective, Management, and Analytical scale in patients treated with 26.2-30.8 Gy vs. 30.9-50.0 Gy was 0% and 6%, respectively.

CONCLUSIONS

RT can cure approximately one half of Stage I and one quarter of Stage II, World Health Organization Grade 1 or 2 follicular lymphomas. Follicular lymphomas <3.0 cm can be controlled locally with doses of 27.8-30.8 Gy, and there is a trend toward a higher incidence of late complications with doses of >30.8 Gy. Doses of 25-30 Gy delivered in 15-20 fractions should be examined prospectively in patients with follicular lymphomas of <3.0 cm.

Hematologic recovery after central lymphatic irradiation for patients with stage I-III follicular lymphoma

BACKGROUND

The authors previously reported that central lymphatic irradiation (CLI) can induce molecular remission in patients with Stage I-III follicular lymphoma, as measured by polymerase chain reaction analysis for t(14;18) (q32;q21). Hematologic toxicity has been considered a major consequence of CLI. This study was undertaken to analyze the patterns of hematologic recovery after CLI.

METHODS

Thirty-three patients with Stage I-III follicular lymphoma were treated with CLI between January 1993 and February 1998. CLI consisted of irradiation to mantle, upper two-thirds of abdomen, and pelvic fields. Each field was treated to 30.0-30.6 grays (Gy) at 1.5-1.8 Gy per fraction, with a boost to 36.0-39.6 Gy at the same rate to the sites of macroscopic disease. A break of approximately 4 weeks was given after treatment of each field. Twenty-four patients who were followed for a minimum of 1 year from the end of CLI form the basis of this analysis. Fourteen patients were male. Three patients had Stage I disease, 6 patients had Stage II disease, and 15 patients had Stage III disease. The International Prognostic Index (IPI) for malignant lymphoma was 0 for 5 patients, 1 for 13 patients, and 2 for 6 patients. The Eastern Cooperative Oncology Group performance status was 0 for 21 patients and 1 for 3 patients. The median values for their pretreatment characteristics were as follows: age, 60 years (range, 34-73 years); height, 173 cm (range, 155-193 cm); weight, 79 kg (range, 57-107 kg); body surface area (BSA), 1.95 m(2) (range, 1.61-2.31 m(2)); bone marrow cellularity, 27%(range, 2-75%), platelet count, 233,000/mm(3) (range, 139,000-339,000/mm(3)), white blood cell (WBC) counts, 6400/mm(3) (range, 4200-10,900/mm(3)); and hemoglobin, 14.5 mg/dL (range, 11.8 -16.6 mg/dL). The median duration of CLI was 159 days (range, 137-345 days). Ten patients had cardiovascular disease. The number of sites receiving a boost dose of > or = 36.0 Gy was 0 sites in 1 patient, 1 site in 6 patients, 2 sites in 11 patients, 3 sites in 5 patients, and 4 sites in 1 patient. The platelet, hemoglobin, and WBC counts were followed every 3 months after completion of CLI. These counts were normalized to the pretreatment counts for statistical analyses. Univariate and multivariate analyses were performed to investigate the correlations between patient factors and hematologic status at 1 year posttreatment. Pearson correlation analysis was used for the continuous factors (patient age, height, weight, BSA, bone marrow cellularity, and duration of CLI), and the Mann-Whitney test was used for categoric factors (IPI, gender, performance status, stage, number of sites receiving > or = 36.0 Gy, and presence or absence of cardiovascular disease).

RESULTS

There was continued recovery, essentially approaching the pretreatment levels, over 3 years for platelet, WBC, and hemoglobin counts. Factors that were associated significantly with normalized platelet counts at 1 year by univariate analyses were age (P = 0.015) and cardiovascular disease (P = 0.041). Age was the only significant factor by multivariate analyses, with older patients having lower platelet counts at 1 year posttreatment. No factors were found that were associated significantly with 1-year normalized WBC or hemoglobin levels by either univariate or multivariate analyses.

CONCLUSIONS

All three of the hematologic components (platelets, WBC, and hemoglobin) essentially recover after patients undergo CLI over a 3-year period. Older age was the only significant adverse factor that affected the platelet recovery, as detected by multivariate analysis. (c) 2001 American Cancer Society.