Radiation therapy of early carcinoma of the true vocal cords

Cyberknife Radiosurgery for the Treatment of Head and Neck Cancer: A Systematic Review

Cyberknife radiosurgery is a frameless stereotactic robotic radiosurgery which has shown to deliver better treatment outcomes in the treatment of advanced head and neck (H&N) carcinomas, especially in previously irradiated and recurrent cases. The aim of the study was to perform a systematic review of the available data on the outcomes of Cyberknife radiosurgery for treatment of head and neck cancer and to evaluate its collective outcomes. This systematic review was registered with the university with the registration no. FRP/2019/63 and was approved by the Institutional Review Board (RC/IRB/2019/132). Literature search was performed in the following: PubMed, Science direct, SciELO, MyScienceWork, Microsoft Academ EMBASE, Directory of Open Access Journals, and Cochrane databases with the keywords “Cyberknife,” “oral cancer,” “oropharyngeal cancer,” and “head and neck cancer” and data was extracted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The records identified were 147 manuscripts. Excluded articles included 5 duplicate articles, 33 abstracts, 101 full text articles due to being off-topic, case reports, review, non-English, 1 survey, and 2 other articles containing data extracted from a main study which was already included. A total of 5 articles were evaluated for qualitative synthesis. The mean dose of Cyberknife radiosurgery delivered for previously irradiated recurrent H&N carcinoma patients was 34.57 Gy, with a mean sample size of 5 studied during the period of 2000 to 2016. The available evidence from the systematic review indicates that Cyberknife can be an efficacious treatment option for recurrent previously irradiated H&N carcinoma, especially for nonresectable tumors. There is paucity of homogenous data and studies in this arena; hence, meta-analysis could not be performed. Further standardized studies are essential, especially where the treatment of H&N carcinoma is considered.

Radiation Oncology Applications in Plastic and Reconstructive Surgery: A Nonsystematic Review of Concepts and Principles

SUMMARY

Careful consideration of radiotherapy can determine the success of reconstructive therapy. There is a broad spectrum of radiotherapy modalities, both benign and malignant. Delivery mechanisms differ in the physical design, setup, radiation source, administrable dosage, and mode of delivery. This range of options allows radiation oncologists to tailor individualized treatment; however, radiotherapy concepts can be challenging for nonspecialists. The purpose of this article is to review general radiation oncology concepts, including essential equipment and radiobiology, and provide plastic surgeons with a basic conceptual understanding to facilitate effective multidisciplinary collaboration with radiation oncologists.

Head and neck cancer: an evolving treatment paradigm

Since the inception of this journal in 1948, the understanding of etiologic factors that contribute to and the treatment of head and neck cancer has evolved dramatically. Advances in surgery, radiation therapy, and chemotherapy have improved locoregional control, survival, and quality of life. The outcomes of these treatment modalities have shifted the focus of curative efforts from radical ablation to preservation and restoration of function. This evolution has been documented in the pages of Cancer for the past 6 decades. This review focuses on the evolution of treatment approaches for head and neck cancer and future directions while recognizing the historic contributions recorded within this journal.

Conservation laryngeal surgery versus total laryngectomy for radiation failure in laryngeal cancer

BACKGROUND

Total laryngectomy is the standard of care for surgical salvage of radiation failure in laryngeal cancer. However, the role of conservation laryngeal surgery in this setting remains unclear. The objective was to compare the efficacy of conservation versus total laryngectomy for salvage of radiation failure in patients who initially presented with T1 or T2 squamous cancer of the larynx.

METHODS

A 21-year retrospective analysis of patients who received surgery at a single comprehensive cancer center after definitive radiation therapy is reported. At recurrence, the patients were reevaluated and then underwent a total laryngectomy or, if possible, a conservation laryngeal procedure. The charts of 105 patients who failed radiation treatment for primary laryngeal cancer and who subsequently underwent surgical salvage were reviewed for this study. Eighty-nine were male (84.8%). The mean age was 60.3 years. The median follow-up time after surgery was 69.4 months. Most patients with recurrence after radiotherapy required total laryngectomy (69.5%; 73/105). Conservation laryngeal surgery was performed for 32 patients (31.5%). Concomitant neck dissections were performed on 45 patients (45.5%).

RESULTS

In 14 patients, local or regional recurrence developed after salvage surgery: 9 patients after total laryngectomy (12.3%; 9/73), and 5 patients (15.6%; 5/32) after conservation laryngeal surgery. This difference was not statistically significant, nor was there a difference in disease-free interval for the two procedures (p = .634, by log-rank test). Distant metastasis developed in 13 patients. Most developed in the setting of local and/or regional recurrence, but distant metastasis occurred as the only site of failure in 6 of the patients who had undergone total laryngectomy but in 1 of the conservation surgery patients treated for a supraglottic laryngeal cancer. The overall mortality for patients who underwent total laryngectomy was also higher: 73.74% (54/73) versus 59.4% (19/32) for patients who underwent a conservation approach (p = .011 by log-rank test).

CONCLUSIONS

Although conservation laryngeal surgery was possible in a few patients with local failure after radiotherapy, conservation laryngeal surgery is an oncologically sound alternative to total laryngectomy for these patients.

Radiation therapy of glottic carcinoma: Peter MacCallum Cancer Institute experience

The medical records of patients with T1N0, T2N0 and T3N0 squamous cell carcinomas of the glottis treated at the Peter MacCallum Cancer Institute between January 1983 and October 1988 were retrospectively reviewed. One hundred and twenty-seven patients were identified. There were 93 T1, 26 T2 and eight T3 tumours. These patients were treated with curative radiotherapy (60-70 Gy). The survival from glottic cancer of patients with T1, T2 and T3 tumours at 5 years was estimated to be 97, 62 and 100% respectively. The local disease free survival for T1 and T2 disease at 5 years was estimated to be 82 and 65% respectively. The local disease free survival for T3 tumours at 2 years was estimated to be 63% with 5 year survival not yet reached. The surgical salvage rates for 24 radiotherapy failures were 77, 25 and 66% for T1, T2 and T3 tumours respectively. Radiotherapy remains the treatment of choice for T1 tumours and a viable alternative to primary laryngectomy in more advanced glottic tumours, with salvage surgery in reserve.

Natural history of treated T1N0 squamous carcinoma of the glottis

The records of 373 patients with T1N0 squamous carcinoma of the glottis were examined. Of these, 271 underwent initial hemilaryngectomy; 102 had full-course irradiation for cure. While the overall survival rates of the two initial therapies were similar, failure of the initial treatment modality was approximately twice as frequent in the irradiated patients (34.4%) as in the patients undergoing hemilaryngectomy (16.9%). The effect of this difference in initial failure rate on quality of life and on cost of overall therapy will be discussed.

A therapeutic approach to early vocal cord carcinoma

One hundred and twenty patients with early glottic carcinoma received radiation therapy at the University of Maryland Hospital from 1959 to 1977. The radiation dose ranged from 55 Gy in 4 weeks for small T1a lesions to 65 Gy in 61/2 weeks for T2 lesions. The local control rates by irradiation alone for stages T1a, T1b, and T2 were 92, 91 and 88 per cent, respectively, while 5-year determinate disease-free survival rates were 96 per cent for stage I disease and 88 per cent for stage II disease. Most of the local failures were salvaged by surgery, with a low complication rate. Regional metastases were uncommon, and occurred in 7 per cent in stage I and in 6 per cent in stage II disease. Factors increasing the risk of failures appeared to be bulky tumor, anterior commissure involvement and subglottic extension.

Role of radiation in the management of early vocal cord carcinoma

From 1952-1978, 177 patients with epidermoid carcinoma confined to the true vocal cords with normal mobility (T1NO) were treated with radiation alone. Five- and 10-year adjusted actuarial survival rates for all patients were 97 and 95%, respectively. The tumor recurred in the larynx and/or neck in 16% of patients with T1a (one cord involved) and 23% of the patients with T1b (both vocal cords involved) disease. Radiation failures were surgically salvaged in 89% of patients with T1a disease without anterior commissure involvement, in 60% of those with T1a disease with anterior commissure involvement and in 57% of those with T1b disease. Tumor was ultimately controlled in 97% of the patients with T1a and 90% of the patients with T1b disease. Voice was preserved in 93% of the patients with T1a disease and 77% of patients with T1b disease. Of 121 patients evaluated for voice quality, 77% had good and 22% had fair voice, while only one patient had poor quality of voice. Patients with fair or poor quality voice usually had had salvage hemilaryngectomy. We recommend radiation for all patients with early vocal cord carcinoma.

Management of early glottic cancer

A detailed retrospective analysis of 136 patients with early glottic cancer treated at the University of Louisville, Radiation Center from October, 1953 to December, 1975 was done. Majority of the patients were in the age range of 55 to 74 years. Of them, 89% were male and 85% were Caucasian. The most common histological type was squamous cell carcinoma. The adjusted 5-year survival rate was 84%, with a standard error of 3%. Of these patients, 18% had local failures, and 68% of which were salvaged by surgery. The overall local control rate was 93%. The median time to recurrence was 23 months. There was no case of laryngeal necrosis, and a good function of larynx was achieved in a majority of the patients. Eighteen second cancers were diagnosed in 17 patients during the follow-up. A brief review of the literature is also done in the paper.

Radiation therapy of glottic carcinoma stage I

A detailed retrospective analysis of 81 patients with a diagnosis of glottic carcinoma stage I (T1N0M0) from 1953 to 1975 has been done. Eighty-eight per cent of the patients were male and 80 per cent of the total number were white. The majority of the patients received a dose of 64 Gy in 6 1/2 weeks. The crude 5-year actuarial survival rate was 69 per cent and the adjusted 5-year actuarial survival rate was 86 per cent. Local recurrence occurred in 12 per cent and of these 80 per cent were cured by surgery. The median time of recurrence was 25.5 months. No case of laryngeal necrosis occurred, and 10 second malignant tumors were diagnosed in the follow-up.