A Comparison of Intensity-Modulated Radiotherapy With Simultaneous Integrated Boost With Three-Dimensional Conformal Radiotherapy With Sequential Boost for Locally Advanced Cervical Cancer: A Dosimetric Study.

Objective The aim of this study was to compare the dosimetric criteria between the intensity-modulated radiation therapy (IMRT) technique with a simultaneous integrated boost (SIB) and the three-dimensional conformal radiation therapy (3DCRT) technique with a sequential boost (SB) plans for patients with locally advanced cervical cancer (LACC). Materials and methods A retrospective dosimetric comparison was performed in 15 patients with locally advanced cervical cancer who had previously been treated with fractions of 1.8 Gy up to doses of 45, 54-55.8, and 59.4 Gy in 28-33 sessions using the three-dimensional conformal radiation therapy (3DCRT) technique with a sequential boost (SB) and who had a new planning that was made using the intensity-modulated radiation therapy (IMRT) technique with a simultaneous integrated boost (SIB) in 25 sessions. The conformity index, quality of coverage, homogeneity index, mean doses, maximum doses, and different organ at risk (OAR) dose constraints were calculated for the dosimetric comparison of treatment plans. Descriptive analysis was performed using measures of central tendency and dispersion for the quantitative variables and absolute and relative frequencies for the qualitative variables. The comparison was made using the Wilcoxon signed rank sum test for a type I error level of 0.05. The statistical software Stata 11 (StataCorp LLC, College Station, Texas, USA) was used in the analysis. Results The mean age of the patients was 52 years, 33% were stage IIIB, and 67% had squamous cell carcinomas. The conformity index was 0.74 and 0.46 (difference: 0.28; p<0.01), the quality of coverage was 0.84 and 0.94 (difference: -0.10; p<0.01), and the homogeneity index was 0.12 and 0.070 (difference: 0.052; p<0.01) for IMRT-SIB and 3DCRT-SB, respectively. When the mean doses of the OARs were compared, all were lower with the IMRT-SIB technique, with statistically significant differences in the rectum and bladder. Conclusions The IMRT-SIB technique achieves a greater conformation of the doses on the treatment volumes with a significant reduction of the doses on the bladder and rectum.

Adrenal Pheochromocytoma Treated With Stereotactic Body Radiation Therapy.

Pheochromocytoma is a rare neuroendocrine tumor arising from chromaffin cells in the adrenal medulla. In most cases, it is benign and tends to remain localized. However since it leads to the development of cardiovascular disease, it is associated with high rates of morbidity and mortality. Treatment options include medical, surgical, or ablative measures, which often adequately control the disease. Primary pheochromocytoma is conventionally treated with external beam radiation therapy (EBRT), while stereotactic body radiation therapy (SBRT) is preferred for cases with metastasis. However, literature regarding the use of SBRT for the treatment of primary disease is scarce. This case report describes a patient with an inoperable primary adrenal gland pheochromocytoma who was treated with SBRT, resulting in adequate symptomatic control during clinical follow-up.

Local Control of Primary Dural Central Nervous System Lymphoma Achieved With Radiotherapy.

Primary central nervous system lymphomas (PCNSL) are extranodal non-Hodgkin's lymphomas (NHL) confined to the brain, leptomeninges, eyes, or spinal cord. Primary leptomeningeal lymphoma (PLML), without parenchymal involvement, synchronous cerebrospinal, or systemic disease is rare. The estimated incidence of PLML is 7% of all PCNSL, which in turn accounts for about 2% of all primary brain tumors and 0.8% of all lymphomas. The incidence of PCNSL in Western countries is approximately five cases per million inhabitants per year, and less than 5% of all primary tumors of the central nervous system (CNS), although it is worth mentioning that the incidence seems to be increasing. The largest series of cases reported in the medical literature collect information from no more than nine patients; in these series, the median age at diagnosis is 57 years; in general, all patients present with cerebrospinal fluid alteration, and the median overall survival rate is close to eight months. With our case series, we aim at sharing the experience of four patients diagnosed and treated at the National Cancer Institute between 2010 and 2020, establishing a correlation of the clinical, imaging, and histopathological presentation, the response to treatment based on radiotherapy and chemotherapy, and the clinical outcomes reported in the medical records.