Ajmel Puthawala

Limited external beam and interstitial 192iridium irradiation in the treatment of carcinoma of the base of the tongue: A ten year experience

A total of 70 patients with histologically proven diagnosis of carcinoma of the base of the tongue were treated with primary irradiation between May 1974 through April 1984. Fifty-eight (83%) of these patients had locally advanced tumors (Stage T3, T4, N2, N3). Fifty-one of the 70 (73%) patients had clinically palpable neck nodes at first presentation. All patients received a combination of external and interstitial irradiation. The dose of external irradiation was limited to 45-50 Gy over 4 1/2-5 1/2 weeks. Interstitial volume implants were performed 2-3 weeks after completion of external irradiation. The primary site as well as the vallecula, epsilateral pharyngeal wall, glossopalatine sulcus, tonsillar bed, and pillars were routinely implanted to encompass contiguous spread of the disease. The doses of implant varied according to the stage of disease, that is, 2000-2500 cGy for T1 and T2 lesions, 3000-4000 cGy for T3 and T4 lesions, with typical dose rates of 50-60 cGy per hour. The neck nodes were also separately implanted to deliver additional doses of 2000-4000 cGy in 50-80 hours. Overall, local tumor control was observed in 58 of 70 (83%) patients at minimum follow-up of 2 years. An absolute 3-year disease-free survival of the entire group was 67.0%. Treatment related complications such as soft tissue necrosis and/or osteoradionecrosis occurred in 8 of the 70 (11.4%) patients. The salvage of neck failures and the local failures was feasible in 74% and 46% of the patients, respectively either by surgery or by re-irradiation using interstitial 192iridium implant alone. This treatment region is well tolerated and it preserves the functional and asthetic integrity in most patients.

THE AMERICAN BRACHYTHERAPY SOCIETY RECOMMENDATIONS FOR HIGH-DOSE-RATE BRACHYTHERAPY FOR HEAD-AND-NECK CARCINOMA

PURPOSE To develop recommendations for use of high-dose-rate (HDR) brachytherapy in patients with head-and-neck cancer. METHODS A panel consisting of members of the American Brachytherapy Society (ABS) performed a literature review, added information based upon their clinical experience, and formulated recommendations for head-and-neck HDR brachytherapy. RESULTS The ABS recommends the use of brachytherapy as a component of the treatment of head-and-neck tumors. However, the ABS recognizes that some radiation oncologists are reluctant to employ brachytherapy in the head-and-neck region because of the complexity of the postoperative management and concerns about radiation safety. In this regard, HDR eliminates unwanted radiation exposure and thereby permits unrestricted delivery of clinical care to these brachytherapy patients. The ABS made specific recommendations for previously untreated and recurrent head-and-neck cancer patients on patient selection criteria, implant techniques, target volume definition, and HDR treatment parameters (such as time, dose, and fractionation schedules). Suggestions were provided for treatment with HDR alone and in combination with external beam radiation therapy. It should be recognized that only limited experiences exist with HDR brachytherapy in patients with head-and-neck cancers. Therefore, some of these suggested doses have not been extensively tested in clinical practice. Hence, these guidelines will be updated as significant new outcome data are available. Any clinician following these guidelines is expected to use clinical judgment to determine an individual patients treatment. CONCLUSIONS Little has been published in the clinical literature on HDR brachytherapy in head-and-neck cancer. Based upon the available information and the clinical experience of the panel members, general and site-specific recommendations were offered. Areas for further investigations were identified.

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.

Limited external irradiation and interstitial 192iridium implant in the treatment of squamous cell carcinoma of the tonsillar region

Between January 1976 and March 1982, 80 patients with histologically proven diagnosis of squamous cell carcinoma of the tonsillar region were treated with definitive radiotherapy. Sixty-five (81%) of these patients had locally advanced tumors (Stage III and IV); 49% of patients had clinically palpable cervical lymphadenopathy. All patients received a combined external megavoltage and interstitial irradiation. The dose of external irradiation was limited to 4500-5000 cGy over 41/2 to 51/2 weeks. This was followed by interstitial 192iridium implants to doses of 2000-2500 cGy in 50-60 hours for T1, T2 lesions and 3000-4000 cGy in 60-100 hours for T3 , T4 lesions. The neck masses were also separately implanted to deliver additional doses of 2000-4000 cGy in 50-80 hours. Overall local tumor control was observed in 84% of patients with a minimum follow-up period of 2 years. An absolute 3-year disease free survival of the entire group was 72%. Treatment related complications such as soft tissue necrosis or osteoradionecrosis occurred in 6% (5/80) of patients. The salvage of neck failures and local failures was possible in 78 and 38% of patients, respectively, either by surgery or by re-irradiation employing interstitial 192iridium implants. Functional and esthetic integrity was well preserved in most cases.

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.

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.

Radical hysterectomy and tailored postoperative radiation therapy in the management of bulky Stage 1B cervical cancer

Ninety‐two patients with Stage 1B cervical cancers having a diameter equal to or greater than 4.0 cm were treated with radical surgery. Thirty‐two patients received postoperative radiotherapy because of operative findings suggestive of high risk of pelvic recurrence. All 32 irradiated patients were treated with a standard pelvic field. Four patients also received paranortic radiotherapy, and ten received intravaginal brachytherapy. Postoperative complications were seen in five patients (two nonirradiated, three irradiated). Projected 5‐year survival is 79% (71% 5‐year survival in irradiated patients, and 83% 5‐year survival in nonirradiated patients). Preoperative evaluation of tumor volume was not found to reliably predict histologic high risk factors such as depth of stromal invasion, risk of lymph node metastases, or presence of extracervical/uterine involvement. A primary surgical approach in this group of patients with large‐diameter Stage IB cervical cancers allows definition of those patients who might benefit from a combined surgical and radiotherapeutic approach to treatment based on findings at operation.

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.