A.M. Nisar Syed

Needle displacement during HDR brachytherapy in the treatment of prostate cancer

PURPOSE We used clinical patient data to examine implant displacement between high dose rate (HDR) brachytherapy fractions for prostate cancer to determine its impact on treatment delivery. MATERIALS AND METHODS We analyzed the verification films taken prior to each fraction for 96 consecutive patients treated with HDR brachytherapy boosts as part of their radiation therapy for definitive treatment of organ-confined prostate cancer at our institution. Patients were treated with 18-24 Gy in 4 fractions of HDR delivered in 40 hours followed by 36-39.6 Gy external beam radiation to the prostate. We determined the mean and maximum displacement distances of marker seeds placed in the prostate and of the implanted needles between HDR fractions. RESULTS Mean and maximum displacement distances between fractions were documented up to 7.6 mm and 28.5 mm, respectively, for the implant needles and 3.6 mm and 11.4 mm, respectively, for the gold marker seeds. All displacement of implant needles occurred in the caudal direction. At least 1 cm caudal displacement of needles occurred prior to 15.5% all fractions. Manual adjustment of needles was required prior to 15% of fractions, and adjustment of the CLP only was required in 24%. Most of the displacement for both the marker seeds and needles occurred between the first and second fractions. CONCLUSIONS There is significant caudal displacement of interstitial implant needles between HDR fractions in our prostate cancer patients. Obtaining verification films and making adjustments in the treatment volume prior to each fraction is necessary to avoid significant inaccuracies in treatment delivery.

Long-term results of low-dose-rate interstitial-intracavitary brachytherapy in the treatment of carcinoma of the cervix

PURPOSE Brachytherapy plays a major role in the treatment of patients with carcinoma of the cervix. However, routine intracavitary brachytherapy may not be feasible or adequate to treat locally advanced disease. The purpose of this retrospective study (spanning a 20-year period) was to determine the outcome of interstitial low-dose-rate brachytherapy in the treatment of bulky or locally advanced cervical cancer. The long-term survival and safety of this technique were evaluated, along with its impact on local and locoregional control, disease-free survival, and complications. METHODS AND MATERIALS A total of 185 previously untreated patients with cervical cancer were treated between 1977 and 1997. According to the International Federation of Gynecology and Obstetrics classification, 21 patients had Stage IB (barrel), 77 Stage II, 77 Stage III, and 10 Stage IV disease. All patients were treated by a combination of external megavoltage irradiation to the pelvis to a dose of 5040 cGy followed by interstitial-intracavitary implants to a dose of 40-50 Gy to the implanted volume in two applications. RESULTS Clinical local control was achieved in 152 (82%) of the 185 patients. A 5-year disease-free survival rate of 65%, 67%, 49%, and 17% was achieved for patients with Stage IB, II, III, and IV disease, respectively. Eighteen (10%) of the 185 patients developed Radiation Therapy Oncology Group Grade 3 or 4 late complications. CONCLUSION Patients with locally advanced cervical cancer, or with distorted anatomy, may be treated adequately with interstitial brachytherapy to achieve excellent locoregional control and a reasonable chance of cure with acceptable morbidity.

Temporary iridium‐192 implant in the management of carcinoma of the prostate

The controversy about the treatment of carcinoma of the prostate has increased in the last decade, with most urologists favoring radical prostatectomy rather than primary irradiation. Several reports of persistent tumors in 50% to 90% of patients after external irradiation and permanent iodine‐125 implantation of the prostate have been disturbing. From July 1977 to December 1985, 200 patients with adenocarcinoma of the prostate were treated by combining bilateral pelvic lymphadenectomy and temporary interstitial iridium‐192 implantation of the prostate, followed by external irradiation. Seventy‐four (36%) patients underwent biopsies of the prostate 4 months to 2 years after completion of the irradiation. Only 12 (16%) patients had persistent tumors. Complications were minimized subsequently by dose modifications.

Interstitial low-dose-rate brachytherapy as a salvage treatment for recurrent head-and-neck cancers : Long-term results

PURPOSE Recurrent cancers of the head and neck within previously irradiated volume pose a serious therapeutic challenge. This study evaluates the response and long-term tumor control of recurrent head-and-neck cancers treated with interstitial low-dose-rate brachytherapy. METHODS AND MATERIALS Between 1979 and 1997, 220 patients with prior radiation therapy with or without surgery for primary tumors of the head and neck were treated for recurrent disease or new primary tumors located within previously irradiated volumes. A majority of these patients had inoperable diseases with no distant metastasis. There were 136 male and 84 female patients, and median age was 56 years. All patients had previously received radiation therapy as the primary treatment or adjuvant treatment following surgery, with a median dose of 57.17 cGy (range, 39-74 cGy). The salvage brachytherapy consisted of a low-dose-rate, afterloading Iridium(192) implant, which delivered a median minimum tumor dose of 53 Gy to a mean tumor volume of 68.75 cm(2). Sixty percent of the patients also received interstitial hyperthermia, and 40% received concurrent chemotherapy as a radiosensitizing and potentiating agent. RESULTS At a minimum 6-month follow-up, local tumor control was achieved in 77% (217/282) of the implanted tumor sites. The 2, 5, and 10-year disease-free actuarial survival rates for the entire group were 60%, 33%, and 22%, respectively. The overall survival rate for the entire group at 5 years was 21.7%. Moderate to severe late complications occurred in 27% of the patients. CONCLUSION It has been estimated that approximately 20-30% of head-and-neck cancer patients undergoing definitive radiation therapy have recurrence within the initial treatment volume. Furthermore, similar percentages of patients who survive after successful irradiation develop new primary tumors of the head and neck or experience metastatic neck disease. A majority of such patients cannot be treated with a repeat course of external beam irradiation because of limited normal tissue tolerance, leading to unacceptable morbidity. However, in a select group of these patients, salvage interstitial brachytherapy may play an important role in providing patients with durable palliation and tumor control, as well as a chance for cure.

Consensus guidelines for high dose rate remote brachytherapy in cervical, endometrial, and endobronchial tumors*

PURPOSE A large number of medical centers have recently instituted the use of High Dose-Rate Afterloading Brachytherapy (HDRAB). There is wide variation in treatment regimens, techniques, and dosimetry being used and there are no national standard protocols or guidelines for optimal therapy. METHODS AND MATERIALS The Clinical Research Committee (CRC) of the American Endocurietherapy Society (AES) met to formulate consensus guidelines for HDRAB in cervical, endometrial, and endobronchial tumors. CONCLUSION Each center is encouraged to follow a consistent treatment policy in a controlled fashion with complete documentation of treatment parameters and outcome including efficacy and morbidity. Until further clinical data becomes available, the linear quadratic model can be used as a guideline to formulate a new HDR regimen exercising caution when changing from a Low Dose Rate (LDR) to a HDRAB regimen. The treatments should be fractionated as much as practical to minimize long term morbidity. As more clinical data becomes available, the guidelines will mature and be updated by the Clinical Research Committee of the AES.

Brachytherapy for primary and recurrent nasopharyngeal carcinoma: 20 years' experience at Long Beach Memorial.

PURPOSE We evaluated treatment outcomes of patients with mostly locally advanced primary and recurrent cancer of the nasopharynx managed with interstitial and intraluminal brachytherapy. METHODS AND MATERIALS This is a retrospective analysis of 56 patients with cancer arising from the nasopharynx treated with interstitial and intracavitary afterloading brachytherapy from 1978 to 1997. Patients were divided into three treatment groups: 15 patients with primary cancer (Group 1), 34 patients with recurrent or persistent disease (Group 2), and 7 patients with cancer in the nasopharynx who had history of previous definitive radiation therapy to the nasopharynx for head and neck cancer (Group 3). Fifty-three percent of patients in Group 1 had 1992 AJCC Stage IV disease, and 49% of patients in Groups 2 and 3 had extensive disease (defined as T3, T4, or parapharyngeal extension). Group 1 received megavoltage radiation to 50-60 Gy followed by a boost to the primary site and neck (in cases of persistent neck disease) with a combination of interstitial and intracavitary brachytherapy (mean dose 33-37 Gy). Five patients received chemotherapy, and 6 patients received hyperthermia. Groups 2 and 3 patients were treated with brachytherapy implants (mean dose 50-58 Gy) without external beam radiation. Twenty-five patients received chemotherapy either before or during radiation, and 21 patients received hyperthermia. RESULTS The overall survival at 2, 5, and 10 years for patients in Group 1 was 79%, 61%, and 61%, respectively, and for patients in Groups 2 and 3 combined was 48%, 30%, and 20%, respectively. Cause-specific survival at 2, 5, and 10 years was 87%, 74%, and 74%, respectively, for patients in Group 1; and 82%, 60%, and 60%, respectively, for patients in Groups 2 and 3. Local control at 2, 5, and 10 years was 93%, 93%, and 77%, respectively, for patients in Group 1; and 81%, 59%, and 49%, respectively, for patients in Groups 2 and 3. Control in the neck at 2, 5, and 10 years was achieved in 93%, 93%, and 93% of patients, respectively, in Group 1; and 88%, 81%, and 81%, respectively, for patients in Groups 2 and 3. Disease-free survival was 87%, 74%, and 62%, respectively, for patients in Group 1, and 56%, 41%, and 34%, respectively, for patients in Groups 2 and 3. There were 4 peri-operative deaths. One death (2%) was attributable to the development of late complications. Forty-five percent of patients experienced some form of late complications. CONCLUSION Interstitial afterloading brachytherapy can provide effective treatment for nasopharyngeal cancers, especially for locally persistent/recurrent and locally extensive lesions.

Interstitial iodine-125 implant in the management of unresectable pancreatic carcinoma.

Eighteen patients with locally advanced adenocarcinoma of the head, body and tail of the pancreas were treated by a combination of biliary bypass, external and interstitial irradiation at Southern California Cancer Center of California Hospital Medical Center, Los Angeles, and Memorial Hospital Medical Center of Long Beach, Long Beach, CA, from July 31, 1975 to December 31, 1980. A dose of 3000 to 5000 rad was delivered to the pancreas and regional lymph nodes by external irradiation utilizing megavoltage units and 10,000 to 15,000 rad to the pancreas and metastatic lymph nodes by permanent Iodine‐125 implants. In this group of 18 patients with unresectable carcinoma of the pancreas, excellent palliation of pain, jaundice and vomiting was achieved, with a median survival of 14 months.

Primary invasive carcinoma of the vagina

Because primary carcinoma of the vagina comprises less than 2% of all gynecologic malignancies, the reported experience in the treatment of large numbers of patients is available only from a few major centers and most often encompasses a variety of differences in treatment selection and technique. The objective of this study was to assess the long term results of an interstitial iridium‐192 afterloading implant technique using the Syed‐Neblett dedicated vaginal plastic template.

Treatment of recurrent gynecologic malignancies with iodine-125 permanent interstitial irradiation

PURPOSE To analyze the outcome of permanent 125I interstitial radiotherapy for unresectable retroperitoneal recurrences of gynecologic malignancies. METHODS AND MATERIALS A retrospective review of 20 patients treated between 1979 and 1993 was performed to evaluate survival and morbidity associated with the interstitial 125I technique. RESULTS Nineteen tumors were located on the lateral pelvic wall and one in the para-aortic region. Eight patients, not previously irradiated, received external beam radiotherapy (EBRT) along with 125I interstitial implants placed at the time of celiotomy. Nineteen (95%) are dead of disease at 1-69 months of follow-up. The median survival was 7.7 months for patients treated with 125I alone and 25.4 months for those treated with both 125I and EBRT. One patient is alive without evidence of disease 69 months after 125I implantation. Fistulas, bowel obstructions, and fatal complications occurred only among patients previously irradiated. CONCLUSIONS When used in a previously irradiated field, 125I interstitial radiotherapy has major morbidity and is unlikely to be associated with cure or long-term survival. In radiotherapy-naive patients with unresectable isolated recurrent gynecologic malignancies, 125I implants and EBRT are feasible and occasionally may contribute to long-term disease-free survival.

Interstitial brachytherapy in the treatment of advanced and recurrent vulvar cancer

OBJECTIVE Our purpose was to evaluate the role of interstitial brachytherapy in vulvar cancer management. STUDY DESIGN From 1985-1992 we performed a retrospective study of patients treated at the University of California, Irvine Medical Center, and Long Beach Memorial Medical Center. RESULTS Eleven patients received interstitial brachytherapy, with (n = 5) or without (n = 6) external beam radiotherapy, for locally advanced (n = 5) or recurrent (n = 6) vulvar cancer. Local control was achieved in all patients. Ten patients have died of disease at a mean interval of 33 months from the time of treatment, with 9 patients having maintenance of local control at death. One patient is alive without disease after 77 months of follow-up. There were 2 cases of local necrosis (18%) and 1 case of rectovaginal fistula (9%). CONCLUSION Local control of advanced vulvar cancer can be achieved with interstitial brachytherapy, with or without external beam radiotherapy. With improved systemic therapy this treatment modality may be used to salvage women with bulky, symptomatic tumors.