Intraoperative radiation therapy for the treatment of recurrent retroperitoneal and pelvic tumors: a single-institution analysis

Treatment of recurrent malignant pheochromocytoma with a novel approach: A case report and review of literature

INTRODUCTION

Pheochromocytomas are rare catecholamine-secreting tumors with a high potential for recurrence post-surgery, necessitating prolonged follow-up. This case highlights the diagnostic and therapeutic challenges in managing recurrent pheochromocytoma.

CASE PRESENTATION

A 25-year-old female, with a history of left pheochromocytoma treated with adrenalectomy a decade earlier, presented with a right adrenal mass. Despite controlled hypertension, elevated urine metanephrines suggested recurrence. Imaging showed a right adrenal mass and suspicious left paraaortic lymph nodes, confirming the diagnosis of recurrent malignant pheochromocytoma in the left adrenal bed and right adrenal gland, with metastasis to the paraaortic lymph nodes. The patient underwent right adrenalectomy coupled with cytoreductive surgery (CRS) in the form of excision of left-sided adrenal bed recurrence and left paraaortic lymph node dissection, intraoperative radiation therapy (IORT), and hyperthermic intraperitoneal chemotherapy (HIPEC). On follow-up six years later, the patient remains free from recurrence.

DISCUSSION

This case illustrates the importance of continued surveillance in pheochromocytoma patients, even those with a low-risk profile. The recurrence in this case, despite a smaller initial tumor size and no genetic predispositions, underscores the unpredictable nature of pheochromocytomas. The successful management with CRS, IORT, and HIPEC emphasizes the need for a personalized and multifaceted treatment approach.

CONCLUSION

Pheochromocytoma patients, including those initially considered low risk, require long-term monitoring due to the risk of recurrence. The utilization of CRS, IORT, and HIPEC in this case was pivotal in managing the recurrent and metastatic malignant disease effectively, demonstrating the significance of a comprehensive, multidisciplinary treatment strategy in such complex cases.

Adamantinoma Metastasis to the Pelvis and Ovaries: A Case Report and Literature Review

Adamantinoma, constituting a minute fraction of primary bone tumors, poses a diagnostic challenge due to its ambiguous histogenesis. This report outlines a distinctive case involving a 27-year-old female with a history of right tibial adamantinoma, presenting with bilateral pulmonary emboli and metastasis to the ovaries and pelvic lymph nodes. Following en bloc resection five years earlier, the patient underwent debulking surgery with hyperthermic intraperitoneal chemotherapy (HIPIC) and intraoperative radiotherapy (IORT) as a palliative measure. The procedure achieved substantial pelvic tumor reduction, and subsequent follow-ups indicated a favorable postoperative trajectory. This case underscores the rarity of adamantinoma metastasis to the ovaries and pelvis, being the first reported instance, shedding light on the challenges and potential benefits of a multimodal palliative approach. Further research is warranted to refine treatment strategies for metastatic adamantinoma and enhance patient outcomes.

Dose-volume parameters comparison of organs at risk between the prone and supine positions in pelvic tumors using 3D-CRT

AIMS

Cancer is a major public health problem worldwide, the leading cause of death in developed countries. Radiotherapy is an important treatment for many malignancies. The main purpose of this study was to compare the two techniques of supine and prone in prostate and rectal cancers using DVH extraction parameters.

METHODS AND MATERIAL

Clinical and dosimetry data of 41 rectal and prostate cancer patients were evaluated in both the supine and prone positions with belly board. Administered dose was daily 180 cGy. The four box fields in the first phase and two lateral fields in the second phase with 18 MV photon fields were used. Each patient underwent CT scan, at both the positions using a contrast agent with a full bladder.

STATISTICAL ANALYSIS USED

By using IBM SPSS software v23, all the data were described. The normal distribution of the data was performed using the KS sample statistical test. For data analysis, paired t test was used in the normal data and the Wilcoxon test was used in the non-normal data.

RESULTS

In patients with rectal cancer, there is no change in the received minimum dose by organs at risk. A significant decrease in received maximum dose, except for the prostate organ, could be due to the spatial proximity of the two organs to each other. Also, the received average dose in the small intestine was significantly reduced (P = 0.005). But in other organs, the dose reduction was not significant. In patients with prostate cancer, there is no change in the received minimum dose by OARs, except for the bladder organ (P = 0.003). Except the bladder organs (P = 0.011), there is no significant decrease in the received average dose by OARs. The maximum dose of the OARs is significantly reduced, except for the colon where there was not much overlap in the PTV, in addition to receiving the dose in the range. There was no significant relationship between CI in the rectal field and UI in the prostate field (P > 0.05), but there was a significant relationship between CI in the prostate field and UI in the rectal field with change in patient position.

CONCLUSIONS

In the prone position, in both patients' groups, the OARs receive an optimal and better dose than the supine position, especially the small intestine organ in the rectal field and the bladder and rectum organs in the prostate field. However, it seems that this change in the position of rectal cancer patients is ineffective in reducing the dose of prostate and needs further investigation.

Delivery of intensity-modulated electron therapy by mechanical scanning: An algorithm study

Purpose

In principle, intensity-modulated electron therapy (IMET) can be delivered through mechanical scanning, with a robotic arm mounting a linac.

Materials and methods

Here is a scanning algorithm to identify the back-and-forth, top-to-bottom (zigzag) pattern scan sequence. The algorithm includes generating beam positions with a uniform resolution according to the applicator size; adopting discrete energies to achieve the depth of 90% dose by compositing energies; selecting energy by locating the target's distal edge; and employing the energy-by-energy scan strategy for step-and-shoot discrete scanning. After a zigzag scan sequence is obtained, the delivery order of the scan spots is optimized by fast simulated annealing (FSA) to minimize the path length. For algorithm evaluation, scan sequences were generated using the computed tomography data of 10 patients with pancreatic cancer undergoing intraoperative radiotherapy, and the results were compared between the zigzag path and an optimized path. A simple calculation of the treatment delivery time, which comprises the irradiation time, the total robotic arm moving time, the time for energy switch, and the time to stop and restart the beam, was also made.

Results

In these clinical cases, FSA optimization shortened the path lengths by 12%-43%. Assuming the prescribed dose was 15 Gy, machine dose rate was 15 Gy/s, energy switch time was 2 s, stop and restart beam time was 20 ms, and robotic arm move speed was 50 mm/s, the average delivery time was 124±38 s. The largest reduction in path length yielded an approximately 10% reduction in the delivery time, which can be further reduced by increasing the machine dose rate and the robotic arm speed, decreasing the time for energy switch, and/or developing more efficient algorithms.

Conclusion

Mechanically scanning IMET is potentially feasible and worthy of further exploration.

Retroperitoneal Sarcomas: a Current Review on Management

Retroperitoneal sarcomas are heterogeneous tumours with variable disease biology and outcomes. The prognosis is primarily related to tumour histology and grade as well as the ability to achieve margin negative resection. Surgery involves compartment or contiguous organ resection to achieve the above goal. Careful utilization of neoadjuvant and adjuvant strategies like radiotherapy and/or chemotherapy can lead to improvement in margin status, thereby contributing to better local control and possibly reducing systemic dissemination. Use of targeted therapies has paved newer pathways of treatment integration centred on molecular and genetic targets. The aim of this review is to update the reader on all aspects of retroperitoneal sarcoma management including emphasis on pertinent and landmark trials in this regard.

Feasibility and Safety of Intraoperative Radiotherapy with Low Energy X-ray Photon Therapy for Recurrent Gynecological Cancer: A Case Series

Objectives: To evaluate the feasibility and safety of low energy X-ray photon intraoperative radiotherapy (IORT) as an adjuvant therapy for recurrent gynecological cancer.Methods: Medical records of all recurrence gynecological cancer patients who underwent IORT were reviewed. Results: Between January 2018 and December 2021, five women (including cervical cancer (n = 2), endometrial cancer (n = 2), and uterine leiomyosarcoma (n = 1)), who underwent IORT and surgical resection for recurrent gynecologic cancer were reviewed. A median dose of 15.62 Gy (range, 12 to 20 Gy) was used for IORT. Repeated IORT and surgical resection was performed in two women. Three women experienced local recurrence, and three women died during follow-up. The 1-year local control rate was 60%. The 2-year overall survival rate was 30%. There was no Clavien–Dindo classification grade III–V complication. Conclusion: IORT using low energy X-ray photon therapy seems to be feasible and safe as an adjuvant therapy in women who underwent salvage surgery for recurrent gynecologic cancer. However, large-scale prospective studies are needed to confirm our findings and evaluate its efficacy.

Intraoperative electron beam radiotherapy and perioperative high-dose-rate brachytherapy in previously irradiated oligorecurrent gynecological cancer: clinical outcome analysis

BACKGROUND

Pelvic recurrences from previously irradiated gynecological cancer lack solid evidence for recommendation on salvage.

METHODS

A total of 58 patients were included in this clinical analysis. Salvage surgery was performed for locoregional relapse within previously irradiated pelvic area after initial surgery and adjuvant radiotherapy or radical external beam radiotherapy. The primary tumor diagnosis included cervical cancer (n = 47, 81%), uterine cancer (n = 4, 7%), and other types (n = 7, 12%). Thirty-three patients received adjuvant IOERT (1984-2000) at a median dose of 15 Gy (range 10-20 Gy) and 25 patients received adjuvant PHDRB (2001-2016) at a median dose of 32 Gy (range 24-40 Gy) in 6, 8, or 10 b.i.d. fractions.

RESULTS

The median follow-up was 5.6 years (range 0.5-14.2 years). Twenty-nine (50.0%) patients had positive surgical margins. Grade ≥ 3 toxic events were recorded in 34 (58.6%) patients. The local control rate at 2 years was 51% and remained stable up to 14 years. Disease-free survival rates at 2, 5, and 10 years were 17.2, 15.5, and 15.5%, respectively. Overall survival rates at 2, 5, and 10 years were 58.1, 17.8, and 17.8%, respectively.

CONCLUSIONS

IOERT and PHDRB account for an effective salvage in oligorecurrent gynecological tumors. Patients with previous pelvic radiation suitable for salvage surgery and at risk of inadequate margins could benefit from adjuvant reirradiation in form of IOERT or PHDRB. However, the rate of severe grade ≥ 3 toxicity associated with the entire treatment program is relevant and needs to be closely counterbalanced against the expected therapeutic gain.