RESUMEN
Therapeutic strategies for patients with locally advanced rectal cancer (LARC) who are achieving a pathological complete response (pCR) after neoadjuvant radio-chemotherapy (neoCRT) are being increasingly investigated. Recent trials challenge the current standard therapy of total mesorectal excision (TME). For some patients, the treatment strategy of "watch-and-wait" seems a preferable procedure. The key factor in determining individual treatment strategies following neoCRT is the precise evaluation of the tumor response. Contrast-enhanced computer tomography (ceCT) has proven its ability to discriminate benign and malign lesions in multiple cancers. In this study, we retrospectively analyzed the ceCT based density of LARC in 30 patients, undergoing neoCRT followed by TME. We compared the tumors´ pre- and post-neoCRT density and correlated the results to the amount of residual vital tumor cells in the resected tissue. Overall, the density decreased after neoCRT, with the highest decrease in patients achieving pCR. Densitometry demonstrated a specificity of 88% and sensitivity of 68% in predicting pCR. Thus, we claim that ceCT based densitometry is a useful tool in identifying patients with LARC who may benefit from a "watch-and-wait" strategy and suggest further prospective studies.
RESUMEN
BACKGROUND: This study reports the first results of durometrically measured hardness of human pancreas and investigates its correlation to palpatory determined hardness, grade of pancreatic fibrosis, and preoperatively determined radiodensity. METHODS: Fifty-two patients with pancreatic resections were prospectively recruited. Hardness of samples from pancreatic cancer, chronic pancreatitis, and normal pancreas was measured using a durometer on a 0-100 Shore units (SU) scale. Three pancreatic surgeons palpated the pancreas and reported their assessment of hardness on a subjective 0-100 "Bochum units" (BU) scale. Radiodensity and fibrosis of pancreatic tissue were used for comparison. RESULTS: Pancreatic hardness differed significantly in normal pancreas, chronic pancreatitis, and pancreatic cancer; 30 SU, 51 SU, and 65.8 SU, respectively. Palpatory hardness of normal pancreas was 20 BU and of pancreatitis 60 BU. It correlated well to durometric readings: r(2)=0.56, P<0.00001. Fibrosis grade and radiodensity correlated neither to durometry nor to palpation. Pancreatic leak developed 4/20 (20%) patients with normal pancreas vs. 1/32 (3.1%) with chronic pancreatitis in the resection margin, P<0.05. CONCLUSIONS: Palpatory assessment of pancreatic hardness performed by experienced surgeons correlated well to durometric measurements and remains the method of choice for intraoperative decision making. Durometry was more precise and should be considered in studies on pancreatic texture and for teaching purposes. Hardness and fibrosis grade appeared to be independent characteristics of pancreatic texture.
