International Journal of Radiation Oncology*Biology*Physics
Clinical investigation: breastTimescale of evolution of late radiation injury after postoperative radiotherapy of breast cancer patients
Introduction
The gradual success of cancer treatment has led to longer patient survival. Unfortunately, this carries with it the penalty of providing a greater opportunity for late effects to appear, increase in severity, and impact on the quality of life of the patient. Cancer is a disease that requires a long follow-up to monitor any tumor recurrence and to fully understand the toxicity of any treatment.
The incidence of complications involving muscles and nerves increases with time after radiation 1, 2. Late damage becomes more severe, progresses with time, and usually cannot be halted or reversed. Several papers have been published in which radiation-induced brachial plexus neuropathy (BPN) has been described 3, 4, 5, 6, 7, 8, 9. Radiation using large doses per fraction is less well tolerated by the brachial plexus than small doses per fraction (10). A couple of case reports have also been published on BPN after mantle radiotherapy to a dose of 40 Gy in 20 fractions for Hodgkin’s disease 11, 12. Other nerves such as the phrenic nerve (11) and the recurrent nerve (13) can also be affected, leading to more subtle symptoms.
Most of the studies and conclusions about the evolution of BPN are based on follow-ups that do not extend more than 5 years, at which time it is often assumed that all the late effects will have been detected. It is important to test that assumption and to see whether more damage appears in late reacting tissues if the patients are studied for a longer period. If there is further progression beyond 5 years, either in incidence or in severity, it will obviously be important to pay particular attention to the follow-up interval when comparing morbidity reports from different trials that do not have the same overall time since treatment. Only long-term follow-up can determine the ultimate risks of radiotherapy.
In the early 1960s a University Hospital with an Oncology Department was first established in Umeå. This provided the only radiation resources for the northern geographic half of Sweden. Some patients received surgical treatment in their local hospital, but all were sent to Umeå University hospital for their radiotherapy.
The first case of BPN was observed in 1965 at the radiotherapy department in Umeå, 2 years after the start of a hypofractionated telecobalt treatment modality for postoperative treatment of breast cancer. A cohort of 71 patients treated with this technique from March 1963 to March 1965 was defined (14) and has been followed for 34 years. In the present paper we focus on the incidence and prevalence of fibrosis, vocal cord paresis, and Grade 3 and Grade 4 neuropathy. The time of appearance and pattern of progression of the damage has been analyzed.
Section snippets
Patients
These breast cancer patients were treated with postoperative radiation therapy after radical mastectomy by a standardized 60Co technique during the period March 1963–March 1965. The patient characteristics are presented in Table 1. All medical records of these 71 patients were still available and were reviewed. The patient files included details of the diagnosis and staging of the breast cancer and details of the surgery and the subsequent follow-up. No analyses existed for hormone receptor
Results
The median survival for the whole group was 12 years and there was a threefold increase in the median survival in patients who were below the median age at treatment, relative to the older group (28 years versus 9 years). The 5, 10, 20, 30, and 34-year actuarial overall survival rates for the whole group are 81%, 59%, 38%, 25%, and 17% respectively.
The time course of evolution of injury is illustrated in Table 3 for fibrosis, BPN, vocal cord paresis (VCP), and Grade 3 or Grade 4 neurological
Discussion
The present long-term follow-up of a homogeneously treated group of patients has provided some insight into the evolution of late effects after overtreatment with radiation. There is no comparable long-term follow-up in a group with such a high survival rate, especially among the younger women where it is almost 50% at 30 years. The delayed incidence of neuropathy among these patients could develop because there were so many long-term survivors and these late morbidities could be detected due
References (17)
Dose–volume effects in the spinal cord
Radiother Oncol
(1993)- et al.
Radiation-induced brachial plexopathyNeurological follow-up in 161 recurrence-free breast cancer patients
Int J Radiat Oncol Biol Phys
(1993) - et al.
Radiation-induced brachial plexus injuryFollow-up of two different fractionation schedules
Radiother Oncol
(1990) - et al.
Brachial plexus neuropathy following mantle radiotherapy
Clin Oncol (R Coll Radiol)
(1998) - et al.
Late radiation injury to muscle and peripheral nerves
Int J Radiat Oncol Biol Phys
(1995) - et al.
Normal tissue tolerance and management of radiation injury
Semin Vet Med Surg Small Anim
(1995) - Bates T, Evans R. Report of the independent review commissioned by The Royal College of Radiologists into brachial...
- Ebner I, Anderl H, Mikuz G, Frommhold H. [Plexus neuropathy: tumor infiltration or radiation damage]. Rofo Fortschr Geb...
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