A conservative approach to treatment of patients with squamous cell carcinoma from unknown head and neck primary cancers compares favorably with results of other reported more aggressive protocols utilizing comprehensive irradiation or concurrent chemoradiation, according to study results reported by Rajan S. Patel, MBChB, MD, April 29 at the American Head and Neck Society’s program during the Combined Otolaryngology Spring Meeting.
Representing the Sydney Head and Neck Cancer Institute in Australia, Dr. Patel told the audience that over the past 20 years, his facility had adopted a conservative approach with the intent of minimizing morbidity and reserving additional treatment for salvage. Treatment has been focused on the clinically involved neck only, by way of ipsilateral neck dissection and adjuvant postoperative neck irradiation in selected cases.
The optimal treatment of metastatic cervical squamous cell carcinoma arising from an unknown primary site [SCCUP] in the head and neck is unclear, Dr. Patel said. There is no real evidence that survival is greater with aggressive treatment.
Analysis of Protocol
The purpose of Dr. Patel’s study was to determine the efficacy of the treatment protocol followed at the Sydney Head and Neck Cancer Institute, and to analyze recurrence and survival following treatment, with particular reference to patterns of treatment failure.
The 20-year retrospective study looked at 70 patients with SCCUP. Neck dissection alone was done in patients with pathological neck stage 1 (pN1) disease confined to the lymph node. All remaining patients received neck dissection and adjuvant postoperative irradiation of the involved, dissected neck. Indications for adjuvant postoperative neck irradiation included previous open biopsy, extracapsular spread (ECS), and advanced neck disease (pN2 or pN3).
Dr. Patel said that primary tumors subsequently emerged in eight patients, at a median of 18 months after neck dissection. Postoperative adjuvant radiotherapy was planned for all of these patients according to the Sydney protocol, but two patients refused. Three patients had undergone negative biopsy of what ultimately proved to be the primary site. Salvage treatment was undertaken in six of the eight and included surgery and adjuvant radiotherapy in four patients and surgery alone in two. Of the six patients who had salvage treatment, three are alive and disease-free, while three died. One patient died two months after treatment and the eighth patient was lost to follow-up.
Fourteen patients experienced cancer recurrence with a median time of nine months. Histology demonstrated ECS in all but one patient. Ipsilateral (dissected) neck failure occurred in nine patients who were rated pN2 or pN3. All these patients had received postoperative adjuvant neck irradiation.
Salvage treatment (including neck dissection, adjuvant postoperative irradiation, and radiotherapy) was attempted in eight patients. Two patients remain disease-free at 13 and 45 months following salvage therapy, one is alive with disease two months after salvage therapy, and the remaining five patients died. Salvage was unsuitable because of advanced regional and distant disease in five patients, four of whom died within one month.
Five patients’ cancers recurred at distant sites a median of nine months following initial treatment, and four of these have died.
Of the total study cohort of 70 patients, cancer recurred in 27 patients following initial treatment. Of these, five remain disease-free following salvage treatment. Disease-specific survival and overall survival at five years were 62% and 56%, respectively, with a trend toward worse disease-specific survival in patients with pN3 stage. In total, 12 of 70 patients suffered complications, with wound-related problems being most frequent.
Dr. Patel noted that SCCUP has a relatively good prognosis, with disease-specific survival rates approaching 70%, and for this reason, many centers adopt aggressive locoregional treatment directed against the most likely mucosal sites based on the location of involved nodes.
Some centers advocate use of aggressive treatment protocols to reduce rates of primary tumor emergency and contralateral neck failure. However, these rates of failure were low in our study and equivalent to those using more aggressive therapies, Dr. Patel said. In our series, salvage was not always successful and this was particularly the case in those with regional failure. Thus, the concept of reserving additional therapy for salvage is not supported by the low rate of successful salvage in our series.
He further noted that their results suggest that more aggressive therapy should be offered to selected patients, namely those with bulky neck disease (pN2 and pN3) and, in particular, patients with macroscopic ECS.
©2007 The Triological Society