Influence of postoperative radiotherapy target volumes in unilateral head and neck carcinoma of unknown primary: A multicentric study using propensity score

OBJECTIVE

To compare the impact of two radiation modalities on loco-regional control, survival and tumour emergence, after node dissection for an unilateral head and neck carcinoma of unknown primary (HNCUP).

MATERIALS AND METHODS

This is a multicentric retrospective study of 138 patients with unilateral HNCUP treated between 2002 and 2017. The absence of primary tumour was assessed by a systematic panendoscopy and positron emission tomography. Neck dissection was initially performed for all patients. Radiation Therapy was delivered on ipsilateral lymph node areas in 62 cases (44%: UL-RT group) and on bilateral lymph node areas and the entire pharyngeal mucosa in 77 cases (56%: COMP-RT group). Impact of radiation modalities on locoregional control and overall survival was assessed using propensity score matching method in order to balance baseline characteristics between the two groups.

RESULTS

The population included 80.4% men, 80.4% smokers, 32.6% P16 positive tumours and 71.0% extracapsular extension. After a median follow-up of 5 years, the locoregional control rate was 80.3% in the UL-RT group and 75.3% in the COMP-RT group (p = 0.688). The corresponding rate of contralateral lymph node recurrence was 0% versus 2.6% (p = 0.503) and the rate of tumour emergence was 11.5% versus 9.1% (p = 0.778). No significant difference was observed between the UL-RT and the COMP-RT groups for overall survival (p = 0.9516), specific survival (p = 0.4837) or tumour emergence (p = 0.9034).

CONCLUSION

UL-RT seems to provide similar outcomes as COMP-RT in unilateral HNCUP post-operative management.

Predictive value of the milking patency test when performing the arterial microanastomosis in head and neck surgery

BACKGROUND

The milking patency test (MPT) is widely used to assess the patency of microanastomosis, despite it being proven to be a traumatic test.

METHODS

We performed microanastomoses with intentional two-wall stitches and asked senior microsurgeons to evaluate the permeability of the anastomoses by looking first at the results of the MPT, then according to artery pulsation.

RESULTS

Microsurgeons were all accurate in evaluating normal or clamped anastomoses. But in anastomoses with defects, the MPT was considered normal 94%, 85%, and 73%. MPT has a positive predictive value of 100% but with a negative predictive value of 27.5%. Observation of the artery pulsation distal to the anastomosis gave similar results.

CONCLUSIONS

Our experiment shows that the two-wall stitches on arterial anastomoses are hardly detected by an MPT. The observed pulsation of the artery gives the same results and could be used instead, without damaging the vessels.