9 min
Radiotherapy Dose Reduction Is Possible With Induction Chemotherapy for Pediatric Nasopharynx Cancer Journal of Clinical Oncology (JCO) Podcast
-
- Science
This JCO Podcast provides observations and commentary on the JCO article, "Treatment of Childhood Nasopharyngeal Carcinoma with Induction Chemotherapy and Concomitant Chemoradiotherapy: Results of the Children’s Oncology Group ARAR0331 Study" by Rodriguez-Galindo et al. My name is Suzanne Wolden, and I am the Director of Pediatric Radiation Oncology at Memorial Sloan Kettering in New York City, USA. My oncologic specialty is Pediatric Radiation Oncology.
This important manuscript summarizes the results of Children’s Oncology Group protocol ARAR0331 for childhood nasopharyngeal carcinoma. The study enrolled 111 patients, of whom 75% were male and 47% were African American, with a median age of 15. Eligible patients had AJCC stage IIb-IVC disease and received three cycles of induction chemotherapy with 5-fluorouracil and cisplatin followed by concurrent cisplatin and radiotherapy. Three patients had progressive disease during induction chemotherapy, eight were removed from the study due to physician or parent preference, and another three were not evaluable. This left 97 patients evaluable for response and concurrent chemoradiotherapy. Responses and radiotherapy treatment plans were not centrally reviewed but were left to the judgement of the treating institution.
All patients received 45 Gy to comprehensive head and neck fields encompassing the nasopharynx and bilateral level I-V lymph nodes. A boost to the nasopharynx and residual gross nodal disease was prescribed based on response. The full dose of 70.2 Gy indicated for stable disease was given to 18.6% of patients while 77.3% received the protocol specified dose for complete or partial response of 61.2 Gy or lower. Another 4.1% of patients received intermediate non-protocol doses of 63.9-66.6 Gy. The trial was amended to reduce the cycles of concurrent cisplatin during radiotherapy to two from three after unacceptable rates of renal and gastrointestinal toxicities were reported.
This trial was limited to patients age 18 years and younger and consisted primarily of American patients. It is notable that the demographics of nasopharynx cancer in these young patients differ significantly from adults with this diagnosis. Most patients are teens since nasopharynx cancer is vanishingly rare in younger children. The majority were male, and nearly half were African-American. Nasopharynx cancer is quite rare in teens of Asian descent, in stark contrast to the adult population. In international series, it has been noted that teens in countries around the Mediterranean also have a relatively high incidence of this rare cancer. The study illustrates that pediatric patients are much more likely than adults to have advanced disease and WHO type III, Epstein Barr virus-associated histology.
Despite a lack of central review, the response rate appears to be quite high to induction therapy as one might expect with WHO type III carcinoma. It is surprising that any patients had progressive disease, and I suspect that the rate of partial and complete response may have been even higher than what is inferred from the radiation boost doses given. Nonetheless, the strategy of induction therapy was highly successful in allowing a large majority of patients to receive reduced doses of radiation. It is important to note that all patients received 45 Gy to initial comprehensive fields rather than the 50 Gy typically used for adults and that smaller, more forgiving fractions of 1.8 Gy were used in comparison to the standard 2 Gy for adult head and neck cancer. While some patients received a standard adult boost dose of 70.2 Gy, 81.4% received a lower boost dose. In most cases, this was the protocol specified 61.2 Gy, a 13% dose reduction. Even with these significantly lower doses, local control was exceptionally high, with only 5.5% of patients experiencing local failure with or without a distant relapse.
The successful reduction in radiothe
This JCO Podcast provides observations and commentary on the JCO article, "Treatment of Childhood Nasopharyngeal Carcinoma with Induction Chemotherapy and Concomitant Chemoradiotherapy: Results of the Children’s Oncology Group ARAR0331 Study" by Rodriguez-Galindo et al. My name is Suzanne Wolden, and I am the Director of Pediatric Radiation Oncology at Memorial Sloan Kettering in New York City, USA. My oncologic specialty is Pediatric Radiation Oncology.
This important manuscript summarizes the results of Children’s Oncology Group protocol ARAR0331 for childhood nasopharyngeal carcinoma. The study enrolled 111 patients, of whom 75% were male and 47% were African American, with a median age of 15. Eligible patients had AJCC stage IIb-IVC disease and received three cycles of induction chemotherapy with 5-fluorouracil and cisplatin followed by concurrent cisplatin and radiotherapy. Three patients had progressive disease during induction chemotherapy, eight were removed from the study due to physician or parent preference, and another three were not evaluable. This left 97 patients evaluable for response and concurrent chemoradiotherapy. Responses and radiotherapy treatment plans were not centrally reviewed but were left to the judgement of the treating institution.
All patients received 45 Gy to comprehensive head and neck fields encompassing the nasopharynx and bilateral level I-V lymph nodes. A boost to the nasopharynx and residual gross nodal disease was prescribed based on response. The full dose of 70.2 Gy indicated for stable disease was given to 18.6% of patients while 77.3% received the protocol specified dose for complete or partial response of 61.2 Gy or lower. Another 4.1% of patients received intermediate non-protocol doses of 63.9-66.6 Gy. The trial was amended to reduce the cycles of concurrent cisplatin during radiotherapy to two from three after unacceptable rates of renal and gastrointestinal toxicities were reported.
This trial was limited to patients age 18 years and younger and consisted primarily of American patients. It is notable that the demographics of nasopharynx cancer in these young patients differ significantly from adults with this diagnosis. Most patients are teens since nasopharynx cancer is vanishingly rare in younger children. The majority were male, and nearly half were African-American. Nasopharynx cancer is quite rare in teens of Asian descent, in stark contrast to the adult population. In international series, it has been noted that teens in countries around the Mediterranean also have a relatively high incidence of this rare cancer. The study illustrates that pediatric patients are much more likely than adults to have advanced disease and WHO type III, Epstein Barr virus-associated histology.
Despite a lack of central review, the response rate appears to be quite high to induction therapy as one might expect with WHO type III carcinoma. It is surprising that any patients had progressive disease, and I suspect that the rate of partial and complete response may have been even higher than what is inferred from the radiation boost doses given. Nonetheless, the strategy of induction therapy was highly successful in allowing a large majority of patients to receive reduced doses of radiation. It is important to note that all patients received 45 Gy to initial comprehensive fields rather than the 50 Gy typically used for adults and that smaller, more forgiving fractions of 1.8 Gy were used in comparison to the standard 2 Gy for adult head and neck cancer. While some patients received a standard adult boost dose of 70.2 Gy, 81.4% received a lower boost dose. In most cases, this was the protocol specified 61.2 Gy, a 13% dose reduction. Even with these significantly lower doses, local control was exceptionally high, with only 5.5% of patients experiencing local failure with or without a distant relapse.
The successful reduction in radiothe
9 min
Top Podcasts In Science