Thesis (Ph.D)-Cairo University, 2025.

Bibliography: pages 97-131.

Background: Pediatric Hodgkin’s lymphoma has a very high cure rate, hence there is a major
focus in reducing the long-term toxicities in this group of patients, through decreasing the use,
dose, volume and field of radiation therapy.


vii

Purpose: To determine the impact of omission of RTH in patients with rapid early response
(RER) and the impact of reducing the volume, field and the dose of RTH in patients with slow
early response (SER).
Methods: This is a comparative study that included All pediatric patients with pediatric
Hodgkin’s lymphoma who were treated with response adapted approach at National Cancer
Institute (NCI), Cairo University, Egypt from 1st January 2019 till the end of December 2022
(study group). Patients with RER in the study group were treated with chemotherapy only,
while patients with SER were treated with both chemotherapy and involved site radiotherapy
(ISRT) to the slow responding sites. They were compared to a historical cohort (control
group) who received their treatment with both chemotherapy and classic involved field
radiotherapy (IFRT) to all patients regardless of the response in the period from 1st January
2014 till the end of December 2018
Results In total, 167 eligible pediatric Hodgkin lymphoma patients were included:
81 patients received PET/CT response adapted therapy between January 2019 and December
2022 (study group). Rapid early response (RER) was observed in 48 patients (59.3%) while
slow early response (SER) was observed in 33 patients (40.7%). 86 patients received their
treatment with both chemotherapy and radiotherapy between January 2014 and December
2018 (control group). The two groups were comparable regarding demographic, clinical and
disease characteristics as well as response to chemotherapy. At the end of follow up, in the
study group, the cumulative 5 years OS and EFS was 96.6% and 90.9 %, respectively.
Patients with RER showed 5 years OS and EFS 100%, and 97.9%, respectively, while Patients
with SER showed 5 years OS and EFS were 92.1 %, 80.3%, respectively. In the control
group, the cumulative 5-year OS and EFS were 96.5%, and 88% respectively. Patients with
RER showed 5-year OS and EFS 100% and 92.7% respectively, while Patients with SER
showed 5-year OS and EFS 88.3% and 76.9%, respectively. There was no significant
difference between the study and control groups in the overall survival (p=0.938) or EFS
(P=0.821). patients with RER in both groups had excellent OS (100%) and there was no
statistically significant difference in EFS (P=0.556). Moreover, patients with SER showed no
significant difference between the two groups in OS (p=0.646) or EFS (p=0.699). Factors
affecting the early response to chemotherapy were studied in the whole cohort (n=167).
Response to treatment was negatively affected by advanced PET stage, high risk group and
the presence of B symptoms.

سرطان الغدد الليمفاوية هودجكين لدى الأطفال لديهمعدل شفاء مرتفع للغاية ، وبالتالي هناك تركيز كبير في الحد من السمية طويلة الأجل في هذه المجموعة من المرضى ، من خلال تقليل استخدام وجرعة ومجال العلاج الإشعاعي.
الغرض من الدراسة هو تقدير تأثير إغفال العلاج الاشعاعي في المرضى الذين يعانون من الاستجابة المبكرة السريعة وتأثير تقليل مجال وجرعة العلاج الاشعاعي في المرضى الذين يعانون من الاستجابة المبكرة البطيئة.
هذه الدراسة شملت مقارنة جميع مرضى الأطفال المصابين بسرطان الغدد الليمفاوية هودجكين الذين عولجوا بنهج معدل استجابة المسح الذري في المعهد القومي للأورام ، جامعة القاهرة ، مصر من 1 يناير 2019 حتى نهاية ديسمبر 2022 (مجموعة الدراسة أ). تم علاج المرضى الذين لديهم استجابة مبكرة في مجموعة الدراسة أ بالعلاج الكيميائي فقط ، بينما تم علاج المرضى الذين يعانون من الاستجابة المتاخرة بكل من العلاج الكيميائي و العلاج الاشعاعي الموجه. تمت مقارنتهم بمجموعة تاريخية تلقوا علاجهم بكل من العلاج الكيميائي و العلاج الاشعاعي لجميع المرضى بغض النظر عن الاستجابة في الفترة من ،1 يناير 2014 حتى نهاية ديسمبر 2018 (المجموعة الضابطة ب).
و قد جائت نتائج البحث بان لا فرق في معدلات النجاة بين المجموعتين.
و بالتالي فانه يمكن حذف العلاج الإشعاعي بأمان في المرضى ذوي الاستجابة المبكرة السريعة. علاوة على ذلك ، في المرضى الذين يعانون من بطء الاستجابة المبكرة ، فإن تقليل المجال (والجرعة في بعض المرضى المختارين) لا يضر بالنتيجة.

Issues also as CD.

Text in English and abstract in Arabic & English.