We examined resected specimens from 40 cases of advanced rectal cancer to determine the extent of microtubular cancer nests and undifferentiated cancer cells (budding). We investigated the relationship between this budding and lymphatic invasion (ly), venous invasion (v), and lymph node metastasis (n), respectively. Moreover, we examined the relationship between ly, budding, and n in the preoperative biopsy specimens of 112 patients, including those of the 40 cases mentioned above. The degree of budding, which was abundant in the actively invasive region, showed a strong correlation with the degree of ly and the existence of n in the resected specimens. Also, budding was recognized in a relatively large portion of the biopsy specimens (52 of 112 [46.4%]) and lymph node metastasis was found in 41 of 52 specimens (78.8%). In 57 specimens, neither ly nor budding was found, and 16 of these specimens (28.1%) had positive lymph nodes. These results implied that the degree of budding in the actively invasive region can be a great help in predicting the presence of n. The presence or absence of budding in preoperative biopsy specimens also can be an important factor (along with the degree of differentiation and ly) in estimating the probability of n.

Background. Ascertaining the optimal distal margin of resection in sphincter‐preserving surgery has become an important problem. This study was designed to examine distal rectal spread of rectal carcinoma and to determine the optimal distal margin of resection for sphincter‐preserving surgery. Methods. Six hundred ten consecutive specimens of resected rectal carcinomas were analyzed retrospectively and pathologically. Results. Sixty‐one patients (10%) had distal spread. In patients who underwent curative surgery, distal spread was observed in only 3.8% (19/505). Distal spread was not found in patients with Stage I disease (0/150), according to the International Union Against Cancer stage. Only 1.2% (2/162) of patients with Stage II disease and 5.1% (10/195) with Stage III disease had slight spread but this was confined within a 1 cm length. Most patients with distal spread had a lower survival rate and died of distant metastasis rather than local recurrence, even after curative surgery. Conclusions. Distal spread seems to be an important risk factor for distant metastasis. Distal margin of resection of 1 cm may be appropriate clearance for most rectal cancers. Cancer 1995;76:388–92.

BACKGROUNDThe goal of the current study was to evaluate the objective response rate and toxicity associated with the oral fluoropyrimidine S‐1 (a combination of tegafur, 5‐chloro‐2,4‐dihydroxypyridine, and potassium oxonate) in patients with previously untreated metastatic colorectal carcinoma.METHODSThirty‐eight patients were enrolled in the study. S‐1 was administered orally at a dose of 40 mg/m2 twice daily for 28 days, followed by a 14‐day rest period. Treatment was repeated every 6 weeks unless disease progression was observed.RESULTSA combined total of 173 courses of S‐1 were administered to the 38 enrolled patients. The median number of courses administered to a given patient was 3.5 (range, 1–18). Although no patient exhibited a complete response to treatment, 15 had partial responses (response rate, 39.5%; 95% confidence interval, 24.0–56.6%). In addition, 5 patients had minor responses, and 14 had stable disease. Four patients were found to have progressive disease after two courses of treatment. The median survival time was 358 days (95% confidence interval, 305–490 days), and the 1‐year survival rate was 47.4%. The most common adverse reactions included myelosuppression and gastrointestinal toxicity; most cases involved Grade 1 or 2 toxicity, but Grade 3 toxicities (anemia [7.9% of patients], neutropenia [5.3% of patients], diarrhea [2.6% of patients], and abnormal bilirubin levels [7.9% of patients]) also were noted. Neither Grade 4 toxicity nor treatment‐related death was observed during the study.CONCLUSIONSOrally administered S‐1 is active against metastatic colorectal carcinoma and has an acceptable toxicity profile. This promising agent has the potential to become a valuable chemotherapeutic option. Cancer 2004. © 2004 American Cancer Society.

The accuracy of intraoperative ultrasonography in diagnosing liver metastasis was evaluated at the time of surgery and at follow-up in 189 patients with colorectal cancers. Evaluation at the time of operation revealed that the sensitivity of intraoperative ultrasonography (93.3%) was significantly (p less than 0.0001) higher than that of preoperative ultrasonography (41.3%), conventional computed tomography (47.1%), and surgical exploration (66.3%). Twenty-two of 104 metastatic liver tumors were detected solely by intraoperative ultrasonography in 18 patients (9.5% of total patients). These 22 tumors were small in size (4 x 4 mm to 15 x 18 mm) and nonpalpable during operation. During the postoperative follow-up period of 18 months or more (mean 35.6 months, median 37.1 months) after colorectal surgery, liver metastases that were unrecognized during surgery appeared in 13 (6.9%) patients. Re-evaluation based on these follow-up results indicated that the sensitivity of intraoperative ultrasonography decreased to 82.3%, which was still significantly (p less than 0.0005) better than that of other methods. Intraoperative ultrasonography was capable of identifying 18 of 31 (58.1%) patients in whom liver metastases were otherwise unrecognized at the time of operation. Intraoperative ultrasonography is more accurate in diagnosing liver metastasis than traditional screening methods, and may have a beneficial impact on the management of colorectal cancer.