Proton Therapy in the Treatment of Anal Cancer in Pelvic Kidney Transplant Recipients: A Case Series

Novel use of adjuvant proton beam therapy in patient with pelvic renal transplant diagnosed with stage IB3 cervical adenocarcinoma

Cervical adenocarcinoma is the second most common histology of cervical cancer and treatment can involve surgery, radiotherapy, systemic therapy, and any combination of the three. Photon external beam radiation therapy and brachytherapy have been the mainstay of radiation treatment options for cervical cancer. Here, we report a case of a 41-year-old patient who had a prior renal transplant and was diagnosed with early-stage, intermediate-risk adenocarcinoma treated with modified radical hysterectomy plus adjuvant proton-beam therapy and vaginal brachytherapy. Treatment was well tolerated with a disease-free interval of 14-months and preserved renal function.

Definitive chemoradiotherapy for a patient with anal cancer after renal transplantation

Patients after renal transplantation are susceptible to secondary malignancies, including anal squamous cell carcinoma. Chemoradiotherapy is the standard treatment for anal squamous cell carcinoma; however, typical irradiation fields for anal cancer encompass a transplanted kidney located in the right iliac fossa, which causes complete renal dysfunction. Thus, typical irradiation fields are not feasible for this population. Additionally, standard concurrent chemotherapy demonstrates nephrotoxicity. Here, we report a case of modified definitive chemoradiotherapy for a 40-year-old patient with locally advanced perianal squamous cell carcinoma after renal transplantation whose abdominoperineal resection was difficult because of a history of repeated open surgeries and long-term steroids. We modified the cranial side of the elective nodal irradiation fields in this case to spare the transplanted kidney, considering the lymph chains of the perianal tumor. We then used continuous 5-fluorouracil to avoid nephrotoxicity of mitomycin C, considering his life expectancy. Modified definitive chemoradiotherapy achieved complete remission with expected toxicities. Now, approximately five years after the procedure, the patient remains disease-free, preserving anal and renal function. Definitive chemoradiotherapy using modified irradiation fields and chemotherapy may be an option for patients with anal squamous cell carcinoma after renal transplantation.

PTCOG Gastrointestinal Subcommittee Lower Gastrointestinal Tract Malignancies Consensus Statement

Purpose

Radiotherapy delivery in the definitive management of lower gastrointestinal (LGI) tract malignancies is associated with substantial risk of acute and late gastrointestinal (GI), genitourinary, dermatologic, and hematologic toxicities. Advanced radiation therapy techniques such as proton beam therapy (PBT) offer optimal dosimetric sparing of critical organs at risk, achieving a more favorable therapeutic ratio compared with photon therapy.

Materials and Methods

The international Particle Therapy Cooperative Group GI Subcommittee conducted a systematic literature review, from which consensus recommendations were developed on the application of PBT for LGI malignancies.

Results

Eleven recommendations on clinical indications for which PBT should be considered are presented with supporting literature, and each recommendation was assessed for level of evidence and strength of recommendation. Detailed technical guidelines pertaining to simulation, treatment planning and delivery, and image guidance are also provided.

Conclusion

PBT may be of significant value in select patients with LGI malignancies. Additional clinical data are needed to further elucidate the potential benefits of PBT for patients with anal cancer and rectal cancer.

Kidney Transplant Cortical Necrosis Observed During Pelvic Radiation Therapy

A 61 year-old female kidney transplant recipient developed radiologic and biopsy-confirmed cortical necrosis in her transplant with elevated serum creatinine levels during concurrent chemoradiation therapy for anal squamous cell carcinoma. Acute anatomic and pathologic changes within a transplanted kidney during chemoradiation therapy have not been described previously in the literature. Further research is required to ascertain the potential significance and long-term clinical consequences of such findings.

De-Escalation of Therapy for Patients with Early-Stage Squamous Cell Carcinoma of the Anus

Simple Summary

Management of early-stage squamous cell carcinoma of the anus (SCCA) remains controversial. The current standard of care treatment of chemotherapy combined with radiation therapy can result in both acute and late toxicity. Alternative therapies, including radiation therapy alone or local excision, may be less toxic, but the role of these therapies in early-stage SCCA remains unclear. Additional options for reducing the intensity of therapy for early-stage SCCA include reduction of radiation dose, altering treatment volumes, modifying chemotherapy type and dosage, and using intensity-modulated radiation therapy to reduce the radiation dose to adjacent normal tissues. Multiple prospective studies are actively investigating the role of de-escalation of therapy in patients with early-stage SCCA.

Abstract

The incidence of squamous cell carcinoma of the anus (SCCA) is increasing, particularly in the elderly, with increased mortality in this age group. While the current standard of care for localized SCCA remains chemoradiation (CRT), completion of this treatment can be challenging with risks for severe acute and late toxicity. It remains unclear if full course CRT is required for the management of early-stage SCCA or if de-escalation of treatment is possible without compromising patient outcomes. Alternative therapies include radiation therapy alone or local excision for appropriate patients. Modifying standard CRT may also reduce toxicity including the routine use of intensity-modulated radiation therapy for treatment delivery, modification of treatment volumes, and selection and dosing of concurrent systemic therapy agents. Finally, we provide an overview of currently accruing prospective trials focused on defining the role of de-escalation of therapy in patients with early-stage SCCA.