Radiation therapy for gastric mucosa-associated lymphoid tissue lymphoma: dose-volumetric analysis and its clinical implications

Radiation Therapy Dose for Limited-stage Extranodal Marginal Zone Lymphomas of the Mucosa-associated Lymphoid Tissues of the Stomach: A Meta-analysis

PURPOSE

To compare the outcomes of 2 standard radiation therapy (RT) doses for limited-stage gastric extranodal marginal zone lymphoma (EMZL) of the mucosa-associated lymphoid tissues.

METHODS AND MATERIALS

A database search was performed to identify articles published from database inception to August 31, 2023. Based on the current standard dose of 24.0 to 30.0 Gy, doses of approximately 30.0 Gy were classified as standard dose (SD), while those of approximately 24.0 Gy were classified as low dose (LD). Pooled estimates of the complete remission (CR) and local recurrence (LR) rates were calculated and compared.

RESULTS

Data from 1072 patients across 30 included studies were analyzed. SD was used in 28 studies (n = 987), while LD was used in 6 studies (n = 85), and both regimens were used in 4 studies. In all included studies, the CR rate was 0.96 (95% CI, 0.94-0.97), and the LR rate was 0.05 (95% CI, 0.04-0.06), showing no significant between-study heterogeneity (τ2 = 0 and I2 = 0% for both; P = .8447 and .9998, respectively). SD and LD resulted in no significant differences in the CR rates (0.96 [95% CI, 0.94-0.97] vs 0.96 [95% CI, 0.89-0.99]; P = .9174) or LR rates (0.05 [95% CI, 0.04-0.06] vs 0.03 [95% CI, 0.01-0.10]; P = .5495).

CONCLUSIONS

Both the SD and LD groups achieved excellent CR and LR rates. These results indicate that the RT dose for limited-stage gastric EMZL may be safely de-escalated without compromising local tumor control.

Radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease which is often associated with Helicobacter pylori (H. pylori) infection. First-line treatment of stage IE and IIE localized gastric MALT lymphoma is based on the eradication of H. pylori. The presence of H. pylori resistance factors such as translocation t (11;18), peri-gastric lymph node involvement and the degree of tumor infiltration of the gastric wall; or lack of response to antibiotic therapy are two main indications to treat with definitive radiotherapy (RT). RT is an effective treatment in localized gastric MALT lymphoma. A moderate dose of 30 Gy allows a high cure rate while being well tolerated. After treatment, regular gastric endoscopic follow-up is necessary to detect a potential occurrence of gastric adenocarcinoma.

Radiotherapy in Early-stage Gastric MALT: Improved Survival Without Increased Cardiac Death

PURPOSE

Radiotherapy (RT) is an effective treatment for localized gastric mucosa-associated lymphoid tissue (MALT) lymphomas unresponsive to antibiotic therapy; however, irradiating the stomach can result in significant radiation to the heart, a risk factor for cardiac disease. We analyzed the Surveillance, Epidemiology, and End Results database to evaluate outcomes related to cardiac disease among patients treated with RT for stage I gastric MALT.

MATERIALS AND METHODS

We identified adult patients treated between 1993 and 2014. The relationship between treatment modality (RT, chemotherapy, combination, and no treatment) and overall survival (OS), mucosa-associated lymphoid tissue-specific survival (MSS), non-mucosa-associated lymphoid tissue-specific survival (non-MSS), and cardiac-specific survival (CSS) was assessed using the Kaplan-Meier estimator and Cox proportional hazards analyses.

RESULTS

A total of 2996 patients (median follow-up, 5.6 y) were analyzed: 27.5% had received RT alone, 12.1% chemotherapy alone, 3.9% chemoradiotherapy, and 56.5% no/unknown treatment (including antibiotic therapy). Compared with RT alone, patients who received chemotherapy alone exhibited worse OS (hazard ratio [HR]: 1.67; 95% confidence interval [CI]: 1.32-2.10; P<0.001) and MSS (HR: 2.10; 95% CI: 1.36-3.23; P=0.001). Although CSS appeared worse in patients who received chemotherapy (HR: 1.56; 95% CI: 0.92-2.66; P=0.10), it was not statistically significant. When comparing orbital and gastric MALT patients, there was no significant difference in CSS (HR: 0.80; 95% CI: 0.49-1.31; P=0.38).

CONCLUSIONS

RT improved survival among patients with stage I gastric MALT without increasing the risk of cardiac death. Those with gastric MALT exhibited similar CSS to those with orbital MALT. Although we cannot analyze nonfatal cardiac toxicity, these results suggest that, absent antibiotic therapy, RT should remain first-line treatment for early-stage gastric MALT.

Combining deep-inspiration breath hold and intensity-modulated radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma: Dosimetric evaluation using comprehensive plan quality indices

Background

Although there have been many attempts to increase the therapeutic ratio of radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma (MALToma), only a few planning studies have reported the efficacy of the modern radiotherapy technique till date. Therefore, we performed the dosimetric comparison among 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) plans, using deep-inspiration breath hold (DIBH) or free-breathing (FB) techniques, to determine the most optimal plan for gastric MALToma.

Methods

We evaluated 9 patients with gastric MALToma for whom 3D-CRT, step-and-shoot IMRT (_SIMRT), volumetric-modulated arc therapy (VMAT), and tomotherapy plans with identical prescribed doses were generated using DIBH or FB computed tomography (CT). Planning target volume (PTV) coverage and non-target doses were calculated for each plan and compared with plan quality metric (PQM) scores.

Results

All 72 plans of 9 patients satisfied our dosimetric goals, and the IMRT plans and 3D-CRT plans had similarly good conformity index values with no differences related to respiratory movement. IMRT plans yielded significantly better doses to the organs-at-risk, and DIBH plans yielded significantly lower liver, heart, and lung D_mean and spinal cord D_max with smaller irradiated volumes compared to FB plans. For the mean PQM scores, VMAT-DIBH and _SIMRT-DIBH yielded the best scores, whereas 3D plans provided reduced beam monitor unit values.

Conclusion

Our findings demonstrate that modern RT technologies (DIBH with VMAT or _SIMRT) could potentially provide excellent target coverage for gastric MALToma while reducing doses to organs-at-risk. However, the relevance of the most optimal plan considering clinical outcomes should be confirmed further in a larger patient cohort.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1263-7) contains supplementary material, which is available to authorized users.

Gastric MALT lymphoma presented with primary perforation in an adolescent: a case report

Background

Primary lymphomas of the gastrointestinal tract are rare, accounting for only 1 to 4% of malignancies arising in the stomach, small intestine, or colon. The stomach is the most common extranodal site of lymphoma and gastric mucosa-associated lymphoid tissue (MALT) lymphoma accounts for 40% of primary gastric lymphoma. Gastric MALT lymphoma reaches its peak incidence between 50 to 60 years of age, therefore, it is rarely encountered in pediatric population. The presenting symptoms of gastric MALT lymphoma are usually nonspecific and primary perforation of gastric MALT lymphoma is uncommon.

Case presentation

A 12 year-old female presented with iron deficient anemia developed gastric perforation. Emergency laparoscopic repair of the perforation was performed and tissue pathology showed gastric MALT lymphoma infiltration. Helicobacter pylori eradication and radiotherapy were sequentially performed. Complete remission was achieved at two months after radiotherapy. To our best knowledge, she is the youngest patient with gastric MALT lymphoma reported in the literature.

Conclusion

Iron deficient anemia is a common presenting manifestation of malignancies in adulthood. In pediatric population, iron deficient anemia is usually caused by nutritional deficient or blood loss. In this case report, we present a teenaged female without previous gastric ulcer history who presented with a rare gastric tumor and an uncommon primary perforation. Even if there is an uncertainty about the exact diagnosis prior to the surgery, the strategy of stomach-preserving therapy by laparoscopy for primary perforation was successful and provided a good quality of life.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1431-9) contains supplementary material, which is available to authorized users.

Benefit of volumetric-modulated arc therapy over three-dimensional conformal radiotherapy for stage I-II extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in the stomach: a dosimetric comparison

Purpose

To retrospectively analyze dosimetric parameters of volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiotherapy (3D-CRT) delivered to extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma) to find out advantages of VMAT and conditions for definite benefits of VMAT.

Materials and Methods

Fifty patients with stage I-II gastric MALT lymphoma received VMAT (n = 14) or 3D-CRT (n = 36) between December 2005 and April 2018. Twenty-seven patients were categorized according to whether the planning target volume (PTV) overlaps kidney(s). Dosimetric parameters were analyzed by dose-volume histogram.

Results

Radiation dose to the liver was definitely lower with VMAT in terms of mean dose (p = 0.026) and V₁₅ (p = 0.008). The V₁₅ of the left kidney was lower with VMAT (p = 0.065). For those with PTV overlapping kidney(s), the left kidney V₁₅ was significantly lower with VMAT. Furthermore, the closer the distance between the PTV and kidneys, the less the left kidney V₁₅ with VMAT (p = 0.037). Delineation of kidney(s) by integrating all respiratory phases had no additional benefit.

conclusions

VMAT significantly increased monitor units, reduced treatment time and radiation dose to the liver and kidneys. The benefit of VMAT was definite in reducing the left kidney V₁₅, especially in geometrically challenging conditions of overlap or close separation between PTV and kidney(s).

MALT lymphoma: epidemiology, clinical diagnosis and treatment

Primary gastric lymphoma (PGL) represents a rare pathology, which can be easily misdiagnosed because of unspecific symptoms of the digestive tract. Histologically, PGL can vary from indolent marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) to aggressive diffuse large B-cell lymphoma (DLBCL). During the years, clinical trials revealed the important role of Helicobacter pylori (H. pylori) in the pathogenesis of gastric MALT lymphoma. Infection with Helicobacter pylori is an influential promoter of gastric lymphomagenesis initiation. Long-term studies revealed that eradication therapy could regress gastric lymphomas.

Gastroenteropancreatic-origin neuroendocrine carcinomas: Three case reports with favorable responses following localized radiotherapy and a review of literature

RATIONALE

The radiotherapy (RT) responses of gastroenteropancreatic (GEP)-origin neuroendocrine tumors remain unclear. We report cases of favorable response after localized RT of GEP-origin neuroendocrine carcinomas (GEP-NECs).

PATIENT CONCERNS

1. An 82-year-old male presented with a lower esophageal mass. Positron emission tomography computed tomography (PET-CT) scan showed a lower esophageal mass and gastrohepatic lymph nodes. 2. A 52-year-old female presented with abdominal discomfort. CT scan showed a 9.8 cm-sized enhancing mass in the lesser sac abutting the stomach, pancreas and liver. 3. A 54-year-old male patient presented with anal pain and bleeding. CT scan showed a remnant mass in the perirectal area after trans-anal excision.

DIAGNOSES

The diagnoses of GEP-NECs were pathologically confirmed by biopsy or excision, and immunohistochemical stainings of Ki-67, CD56, synaptophysin and chromogranin-A.

INTERVENTIONS

1. The patient was treated with definitive RT. 2. The patient was treated with RT after two cycles of etoposide-cisplatin chemotherapy. 3. The patient was treated with adjuvant RT.

OUTCOMES

1. Complete remission was achieved based on CT scan four months after RT. 2. CT scan showed partial regression of the mass with a 5 cm-diameter at six months after RT. Adjuvant chemotherapy was administered after RT. 3. The residual mass was almost completely regressed at CT scan four months after RT.

LESSONS

In cases of GEP-NECs, RT can be a useful treatment modality with favorable tumor response for patients with inoperable conditions or those suffering from bulky tumor masses.

Treatment outcome of diffuse large B-cell lymphoma involving the head and neck: Two-institutional study for the significance of radiotherapy after R-CHOP chemotherapy

This study was performed to analyze the treatment outcome for diffuse large B-cell lymphoma (DLBCL) involving the head and neck and to evaluate the role of radiotherapy in the rituximab era. Fifty-six patients diagnosed with DLBCL involving the head and neck were assessed. All patients were treated with 6 cycles of rituximab, cyclophosphamide, adriamycin, vincristine, and prednisolone (R-CHOP). After chemotherapy, radiation was delivered to the head and neck area in a median dose of 36 Gy. Radiation was delivered using 3-dimensional radiotherapy (n  =  25) or intensity-modulated radiotherapy (n  =  31). Primary endpoints were relapse-free survival (RFS), overall survival (OS), and local control rate. After median follow-up time of 45 months, the 5-year RFS and OS rates were 72% and 61%, respectively. Fourteen (25%) of 56 patients relapsed; 1 had a local relapse, 11 had distant relapses, and 2 had both local and distant relapses. The final local control rate after radiotherapy was 94%. Age, performance status, international prognostic index score, and radiotherapy response were significant prognostic factors for both RFS and OS in the multivariate analysis. Incidence of acute grade 3 and 4 hematologic toxicity was 9% and 4%, respectively. Grade 3 nonhematologic toxicity occurred in 2 (4%) patients, and there was no grade 4 nonhematologic toxicity for the irradiated patients. Excellent local control and survival rates can be achieved with R-CHOP followed by radiotherapy in patients with DLBCL involving the head and neck. Treatment-related toxicity after the introduction of modern radiotherapy was acceptable and limited.