Low-dose radiotherapy for extranodal marginal zone B lymphoma of the lip: Case report and literature review

Abstract Non-Hodgkin lymphoma (NHL) of the lip is extremely rare. It is usually indolent and in early stages a local approach is often indicated. We present a case report of a patient with extranodal NHL of the lip treated with chemotherapy and low-dose radiation treatment (RT). The patient was affected by B-cell NHL of the marginal zone, Stage IAE. After a few months of observation with progressive disease, the patient was submitted to two cycles of chemotherapy with no response. Therefore, he was treated with very low-dose RT consisting of two fractions of 2 Gy. Complete response was observed and after 1-year follow-up, persistent complete response was recorded. In cases of localized disease, especially in patients with comorbidities of poor performance status (PS), low-dose RT can be an appropriate approach with excellent outcomes in terms of effectiveness and low risk of toxicity

Variability of clinical target volume delineation for rectal cancer patients planned for neoadjuvant radiotherapy with the aid of the platform Anatom-e

Objective: Delineation of treatment volumes is a major source of uncertainties in radiotherapy (RT). This is also true for rectal cancer patients undergoing neoadjuvant RT, with a potential impact on treatment quality. We investigated the role of the digital platform Anatom-e (Anatom-e Information Sytems Ltd., Houston, Texas) in increasing the compliance to follow a specific treatment protocol in a multicentric setting. Materials and methods: Two clinical cases of locally advanced rectal cancer were chosen. Participants were instructed to follow the 2009 Radiation Therapy Oncology Group consensus atlas and asked to manually segment clinical target volumes (CTVs), for both patient 1 and 2, on day 1 with and without the use of Anatom-e. After one week (day 2), the same radiation oncologist contoured again, with and without Anatom-e, the same CT series. Intraobserver (Intra-OV) and interobserver (Inter-OV) variability were evaluated with the Dice similarity coefficient (DSC), the Hausdorff distance (HD) and mean distance to agreement (MDA). Results: For clinical case 1, no significant difference was found for Intra-OV and Inter-OV. For clinical case 2, no significant difference was found for Intra-OV but a statistically significant difference was found for Inter-OV in DSC when using or not the platform. Mean DCS was 0.65 (SD: ±0.64; range: 0.58–0.79) for day 1 vs reference volume without Anatom-e and 0.72 (SD: ±0.39; range: 0.67–0.77) (p = 0.03) with it. Mean MDA was lower with Anatom-e (3.61; SD: ±1.33; range: 2.85–4.78) than without (4.14; SD: ±2.97; range: 2.18–5.21), with no statistical significance (p = 0.21) The use of Anatom-e decreased the SD from 2.97 to 1.33. Mean HD was lower with Anatom-e (26.06; SD: ±2.05; range: 24.08–32.62), with no statistical significance (p = 0.14) compared to that without (31.39; SD: ±1.31; range: 26.14–48.72). Conclusions: The use of Anatom-e decreased the Inter-OV in the CTV delineation process for locally advanced rectal cancer with complex disease presentation planned for neoadjuvant RT. This system may be potentially helpful in increasing the compliance to follow shared guidelines and protocols. Keywords: Rectal cancer, Neoadjuvant radiotherapy, Interobserver variability, Contouring, Target volume delineatio