1.Pulsed low-dose rate radiotherapy for recurrent bone sarcomas: case reports and brief review
Ru Xin WONG ; Zubin MASTER ; Eric PANG ; Valerie YANG ; Wen Shen LOOI
Radiation Oncology Journal 2024;42(1):88-94
Purpose:
Re-irradiation for bulky recurrent sarcoma carries significant risks. Pulsed low-dose rate radiotherapy (PLDR) is an attractive option for re-irradiation due to inherent radiobiological advantages.
Materials and Methods:
We present two patients who underwent reirradiation using PLDR technique, followed by a literature review.
Results:
The first case is that of a 76-year-old male who developed an in-field recurrence of a bulky pelvic bone high-grade chondrosarcoma after he was treated with definitive radiotherapy using helical TomoTherapy with a total dose of 66 Gy. The patient was re-irradiated using PLDR with a shrinking field technique; 50 Gy in 2 Gy fractions followed by a boost of 20 Gy in 2 Gy fractions. The patient remains disease-free without significant toxicity 60 months post-irradiation. The second case is that of an 82-year-old female who was treated with a definitive irradiation of 66 Gy in 33 fractions for a right shoulder grade II chondrosarcoma. She developed an in-field recurrence 28 months later and presented with bulky disease causing brachial plexopathy and lymphedema. The patient was re-irradiated with a palliative intent to a total dose of 50 Gy in 2 Gy fractions over 5 weeks using PLDR. Brachial plexopathy resolved shortly after re-irradiation, but local progression near the surface was evident 8 months later. She passed away from unrelated causes 11 months later.
Conclusion
We present two cases highlighting our early experience with PLDR, which was effective in the reirradiation of recurrent bony sarcoma. Our study highlights PLDR as an option for reirradiation in recurrent unresectable tumors.
2.Ceftriaxone-resistant Salmonella spp. in Singapore.
Tse Hsien KOH ; Andre Emmanuel KOH ; Azhar HAMDAN ; Boon Ching KHOO ; Valerie Yang YU ; R T RAYMOND ; Nancy W S TEE
Annals of the Academy of Medicine, Singapore 2008;37(10):900-901
Adolescent
;
Adult
;
Aged
;
Aged, 80 and over
;
Anti-Bacterial Agents
;
pharmacology
;
Ceftriaxone
;
pharmacology
;
Child, Preschool
;
Drug Resistance, Microbial
;
Hospitals, Public
;
Humans
;
Infant
;
Microbial Sensitivity Tests
;
Middle Aged
;
Salmonella
;
classification
;
drug effects
;
isolation & purification
;
Salmonella Infections
;
drug therapy
;
microbiology
;
Singapore
;
beta-Lactamases
;
genetics
;
isolation & purification
3.Feasibility and safety study of ultra-hypofractionated neoadjuvant radiotherapy to margins-at-risk in retroperitoneal sarcoma
Ru-Xin WONG ; Valerie Shi Wen YANG ; Clarame Shulyn CHIA ; Wen Shen LOOI ; Wen Long NEI ; Chin-Ann Johnny ONG
Radiation Oncology Journal 2025;43(1):6-12
Purpose:
Retroperitoneal sarcomas (RPS) are rare tumors that present unique challenges, often due to late presentation, and the proximity of critical organs makes complete surgical resection challenging. This study aimed to assess the feasibility of neoadjuvant short-course radiotherapy (SCRT) targeting margins-at-risk and to assess its potential impact on outcomes.
Materials and Methods:
This is a single-center, prospective, non-randomized feasibility study. SCRT was administered via image-guided volumetric modulated arc therapy, consisting of 5 fractions of daily radiotherapy followed by immediate surgery. As a starting dose, patients were prescribed 25 Gy in 5 fractions. For the escalation stage, patients were prescribed 30 Gy in 5 fractions. Only the presumed threatened surgical margins were delineated for large tumors.
Results:
Patients with either primary or recurrent RPS were recruited. Eight patients underwent SCRT but one patient did not have a resection as planned. Seven patients underwent surgical resection, of whom one passed away 3 months postoperative from a cardiac event. After a median follow-up of 20.5 months for the six postoperative survivors, there were no overt long-term toxicities and one patient relapsed out-of-radiotherapy-field.
Conclusion
SCRT to RPS with a margin boost followed by immediate surgery is worth investigating. A starting dose of 30 Gy in 5 fractions is recommended for further studies. Longer-term follow-up is necessary.
4.Feasibility and safety study of ultra-hypofractionated neoadjuvant radiotherapy to margins-at-risk in retroperitoneal sarcoma
Ru-Xin WONG ; Valerie Shi Wen YANG ; Clarame Shulyn CHIA ; Wen Shen LOOI ; Wen Long NEI ; Chin-Ann Johnny ONG
Radiation Oncology Journal 2025;43(1):6-12
Purpose:
Retroperitoneal sarcomas (RPS) are rare tumors that present unique challenges, often due to late presentation, and the proximity of critical organs makes complete surgical resection challenging. This study aimed to assess the feasibility of neoadjuvant short-course radiotherapy (SCRT) targeting margins-at-risk and to assess its potential impact on outcomes.
Materials and Methods:
This is a single-center, prospective, non-randomized feasibility study. SCRT was administered via image-guided volumetric modulated arc therapy, consisting of 5 fractions of daily radiotherapy followed by immediate surgery. As a starting dose, patients were prescribed 25 Gy in 5 fractions. For the escalation stage, patients were prescribed 30 Gy in 5 fractions. Only the presumed threatened surgical margins were delineated for large tumors.
Results:
Patients with either primary or recurrent RPS were recruited. Eight patients underwent SCRT but one patient did not have a resection as planned. Seven patients underwent surgical resection, of whom one passed away 3 months postoperative from a cardiac event. After a median follow-up of 20.5 months for the six postoperative survivors, there were no overt long-term toxicities and one patient relapsed out-of-radiotherapy-field.
Conclusion
SCRT to RPS with a margin boost followed by immediate surgery is worth investigating. A starting dose of 30 Gy in 5 fractions is recommended for further studies. Longer-term follow-up is necessary.
5.Feasibility and safety study of ultra-hypofractionated neoadjuvant radiotherapy to margins-at-risk in retroperitoneal sarcoma
Ru-Xin WONG ; Valerie Shi Wen YANG ; Clarame Shulyn CHIA ; Wen Shen LOOI ; Wen Long NEI ; Chin-Ann Johnny ONG
Radiation Oncology Journal 2025;43(1):6-12
Purpose:
Retroperitoneal sarcomas (RPS) are rare tumors that present unique challenges, often due to late presentation, and the proximity of critical organs makes complete surgical resection challenging. This study aimed to assess the feasibility of neoadjuvant short-course radiotherapy (SCRT) targeting margins-at-risk and to assess its potential impact on outcomes.
Materials and Methods:
This is a single-center, prospective, non-randomized feasibility study. SCRT was administered via image-guided volumetric modulated arc therapy, consisting of 5 fractions of daily radiotherapy followed by immediate surgery. As a starting dose, patients were prescribed 25 Gy in 5 fractions. For the escalation stage, patients were prescribed 30 Gy in 5 fractions. Only the presumed threatened surgical margins were delineated for large tumors.
Results:
Patients with either primary or recurrent RPS were recruited. Eight patients underwent SCRT but one patient did not have a resection as planned. Seven patients underwent surgical resection, of whom one passed away 3 months postoperative from a cardiac event. After a median follow-up of 20.5 months for the six postoperative survivors, there were no overt long-term toxicities and one patient relapsed out-of-radiotherapy-field.
Conclusion
SCRT to RPS with a margin boost followed by immediate surgery is worth investigating. A starting dose of 30 Gy in 5 fractions is recommended for further studies. Longer-term follow-up is necessary.
6.Feasibility and safety study of ultra-hypofractionated neoadjuvant radiotherapy to margins-at-risk in retroperitoneal sarcoma
Ru-Xin WONG ; Valerie Shi Wen YANG ; Clarame Shulyn CHIA ; Wen Shen LOOI ; Wen Long NEI ; Chin-Ann Johnny ONG
Radiation Oncology Journal 2025;43(1):6-12
Purpose:
Retroperitoneal sarcomas (RPS) are rare tumors that present unique challenges, often due to late presentation, and the proximity of critical organs makes complete surgical resection challenging. This study aimed to assess the feasibility of neoadjuvant short-course radiotherapy (SCRT) targeting margins-at-risk and to assess its potential impact on outcomes.
Materials and Methods:
This is a single-center, prospective, non-randomized feasibility study. SCRT was administered via image-guided volumetric modulated arc therapy, consisting of 5 fractions of daily radiotherapy followed by immediate surgery. As a starting dose, patients were prescribed 25 Gy in 5 fractions. For the escalation stage, patients were prescribed 30 Gy in 5 fractions. Only the presumed threatened surgical margins were delineated for large tumors.
Results:
Patients with either primary or recurrent RPS were recruited. Eight patients underwent SCRT but one patient did not have a resection as planned. Seven patients underwent surgical resection, of whom one passed away 3 months postoperative from a cardiac event. After a median follow-up of 20.5 months for the six postoperative survivors, there were no overt long-term toxicities and one patient relapsed out-of-radiotherapy-field.
Conclusion
SCRT to RPS with a margin boost followed by immediate surgery is worth investigating. A starting dose of 30 Gy in 5 fractions is recommended for further studies. Longer-term follow-up is necessary.
7.Feasibility and safety study of ultra-hypofractionated neoadjuvant radiotherapy to margins-at-risk in retroperitoneal sarcoma
Ru-Xin WONG ; Valerie Shi Wen YANG ; Clarame Shulyn CHIA ; Wen Shen LOOI ; Wen Long NEI ; Chin-Ann Johnny ONG
Radiation Oncology Journal 2025;43(1):6-12
Purpose:
Retroperitoneal sarcomas (RPS) are rare tumors that present unique challenges, often due to late presentation, and the proximity of critical organs makes complete surgical resection challenging. This study aimed to assess the feasibility of neoadjuvant short-course radiotherapy (SCRT) targeting margins-at-risk and to assess its potential impact on outcomes.
Materials and Methods:
This is a single-center, prospective, non-randomized feasibility study. SCRT was administered via image-guided volumetric modulated arc therapy, consisting of 5 fractions of daily radiotherapy followed by immediate surgery. As a starting dose, patients were prescribed 25 Gy in 5 fractions. For the escalation stage, patients were prescribed 30 Gy in 5 fractions. Only the presumed threatened surgical margins were delineated for large tumors.
Results:
Patients with either primary or recurrent RPS were recruited. Eight patients underwent SCRT but one patient did not have a resection as planned. Seven patients underwent surgical resection, of whom one passed away 3 months postoperative from a cardiac event. After a median follow-up of 20.5 months for the six postoperative survivors, there were no overt long-term toxicities and one patient relapsed out-of-radiotherapy-field.
Conclusion
SCRT to RPS with a margin boost followed by immediate surgery is worth investigating. A starting dose of 30 Gy in 5 fractions is recommended for further studies. Longer-term follow-up is necessary.