Background and Study Aims: Endosonographic staging of esophageal carcinoma may be
limited by non-traversable tumor stenoses. Dilation of malignant esophageal strictures
carries a significant risk of esophageal perforation. We therefore evaluated the use
of ultrasonic miniprobes in the staging of stenotic esophageal carcinoma compared
with conventional endoscopic ultrasound.
Patients and Methods: In a blinded, prospective study, which included histopathological
evaluation, 53 consecutive patients (43 male, 10 female, mean age 61 years) with stenosing
esophageal carcinomas were examined preoperatively. Endosonography was done using
the optical GF-UM3 echo endoscope. If tumor strictures were not traversable with this
instrument, a blind esophagoprobe, the MH-908 was used for endosonography. Miniprobe
sonography (MPS) was done during esophagoscopy in all patients. The various imaging
modalities were assessed in terms of complete tumor traversability and correct tumor
staging. Every patient underwent surgical tumor resection.
Results: MPS of the esophagus and proximal parts of the stomach was possible in all
53 patients without prior dilation of tumor stenoses. Endosonography with the GF-UM3
instrument was precluded in 23 patients (43.4 %) while in 20 of the latter patients
the MH 908 esophagoprobe could be passed through tumor stenoses. The overall accuracy
rates for depth of tumor infiltration (T) staging were: 62 % (31/50) for endosonography
(GF-UM3 plus esophagoprobe) and 86.8 % (46/53) for MPS. The accuracy rates for T staging
in tumors traversable both with the GF-UM3 echo endoscope and with miniprobes were
56.7 % (17/30) for GF-UM3 and 80 % (24/30) for MPS. The accuracy rates for T staging
in tumors traversable only with the MH-908 esophagoprobe and with miniprobes were
70 % (14/20) for the MH-908 and 95 % (19/20) for MPS. With regard to the presence
or absence of peri-esophageal metastatic lymph nodes (N staging), the accuracy rates
were 83 % (25/30) for MPS and 70 % (21/30) for the GF-UM3, and 80 % (16/20) for MPS
and 70 % (14/20) for the MH-908.
Conclusion: Compared with conventional endosonography using 7.5-MHz large diameter
instruments, MPS enables: a) safe passage through high-grade malignant esophageal
strictures, achieving b) higher accuracy rates for T staging, and c) similar rates
for N staging. The use of MPS can also represent an improvement in the comfort and
safety of patients. Moreover, miniprobe sonography is highly cost-effective compared
with conventional endosonography. Thus, MPS appears to be a valuable addition to the
armamentarium for staging esophageal carcinoma.
References
UICC TNM Atlas. Illustrated guide to the TNM/pTNM classification of malignant tumours. Berlin; Springer 1992: 3
jmenzel@uni-muenster.de
