Metachronous colorectal cancer

Associations between pathological features and risk of metachronous colorectal cancer

Survivors of colorectal cancer (CRC) are at risk of developing another primary colorectal cancer - metachronous CRC. Understanding which pathological features of the first tumour are associated with risk of metachronous CRC might help tailor existing surveillance guidelines. Population-based CRC cases were recruited from the United States, Canada and Australia between 1997 and 2012 and followed prospectively until 2022 by the Colon Cancer Family Registry. Metachronous CRC was defined as a new primary CRC diagnosed at least 1 year after the initial CRC. Those with the genetic cancer predisposition Lynch syndrome or MUTYH mutation carriers were excluded. Cox regression models were fitted to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for the associations. Of 6085 CRC cases, 138 (2.3%) were diagnosed with a metachronous CRC over a median follow-up time of 12 years (incidence: 2.0 per 1000 person-years). CRC cases with a synchronous CRC were 3.4-fold more likely to develop a metachronous CRC (adjusted HR: 3.36, 95% CI: 1.89-5.98) than those without a synchronous tumour. CRC cases with MMR-deficient tumours had a 72% increased risk of metachronous CRC (adjusted HR: 1.72, 95% CI: 1.11-2.64) compared to those with MMR-proficient tumours. Compared to cases who had an adenocarcinoma histologic type, those with an undifferentiated histologic type were 77% less likely to develop a metachronous CRC (adjusted HR: 0.23, 95% CI: 0.06-0.94). Existing surveillance guidelines for CRC survivors could be updated to include increased surveillance for those whose first CRC was diagnosed with a synchronous CRC or was MMR-deficient.

Colostomy-site carcinoma with primitive phenotype in a rectal cancer patient after achieving pathological complete response with neoadjuvant chemoradiotherapy

Herein, we report a rare case of a carcinoma with primitive phenotype (enteroblastic and/or hepatoid differentiation) occurring at a colostomy site. The patient was an elderly male who underwent neoadjuvant chemoradiotherapy for rectal cancer, followed by abdominoperineal resection. A biopsy specimen for the rectal carcinoma before neoadjuvant chemoradiotherapy was conventional tubular adenocarcinoma. Moreover, a pathological complete response was confirmed in the proctectomy specimen. However, a colostomy-site tumor appeared 6 months after the proctectomy, and it was resected 1 year after the initial proctectomy. The colostomy-site tumor comprised solid to focal glandular growth of atypical polygonal cells with clear to pale eosinophilic cytoplasm and was immunohistochemically positive for cytokeratin, spalt-like transcription factor 4, glypican-3, caudal type homeobox 2, and special AT-rich sequence-binding protein 2. Thus, the tumor was diagnosed as poorly differentiated adenocarcinoma with primitive phenotype, with suggested origin from the colorectal epithelium. Additionally, a multilocular cystic lesion comprising various types of epithelia was found adjacent to the tumor, suggestive of metaplasia or heterotopia. Changes in the histology and immunophenotype, and the findings of an adjacent cystic lesion suggest a metachronous tumor rather than a recurrence of the primary tumor.

Risk factors for metachronous colorectal cancer and advanced neoplasia following primary colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Identifying risk factors for metachronous colorectal cancer (CRC) and metachronous advanced neoplasia could be useful for guiding surveillance. We conducted a systematic review and meta-analysis to investigate risk factors for metachronous CRC and advanced neoplasia.

METHODS

Searches were conducted in MEDLINE, Embase, Web of Science and Cochrane Central Registry of Controlled Trials for articles (searching period: 1945 to Feburary, 2021) that reported the results of an association between any factor and metachronous advanced neoplasia or metachronous CRC. There were no restrictions on the publication date or language. Random effects models were fitted to estimate the combined association between the risk factors and metachronous CRC or advanced neoplasia. The Risk of Bias In Non-Randomised Studies of Interventions tool (ROBINS-I) was used to assess the risk of bias of included studies.

RESULTS

In total, 22 observational studies with 625,208 participants were included in the systematic review and meta-analysis. Of these, 13 studies investigated risk factors for metachronous CRC and 9 for advanced neoplasia. The risks of metachronous CRC or advanced neoplasia were higher if the first CRC was diagnosed in the presence of a synchronous advanced lesion (pooled risk ratio (RR) from 3 studies: 3.61, 95% confidence interval (CI): 1.44-9.05; and pooled RR from 8 studies: 2.77, 95% CI: 2.23-3.43, respectively). The risk of metachronous CRC was lower, but the risk of metachronous advanced neoplasia was higher if the first CRC was distal (compared with proximal) (pooled RR from 3 studies: 0.48, 95% CI: 0.23-0.98; and pooled RR from 2 studies: 2.99, 95% CI: 1.60-5.58 respectively). The risk of metachronous advanced neoplasia increased with age (pooled RR from 3 studies: 1.07 per year of age, 95% CI: 1.03-1.11). There was no evidence that any lifestyle risk factors studied were associated with the risk of metachronous CRC or advanced neoplasia.

CONCLUSIONS

The identified risk factors for metachronous CRC and advanced neoplasia might be useful to tailor the existing surveillance guidelines after the first CRC. There were potential limitations due to possible misclassification of the outcome, confounding and risk of bias, and the findings cannot be generalised to high-risk genetic syndrome cases.

Peristomal adenocarcinoma 16 years after colorectal adenocarcinoma resection with curative intent

Metachronous colorectal cancer is relatively rare, occurring in 0.7-3.6% of patients diagnosed with colorectal adenocarcinoma. Cutaneous metastases are similarly a rare presentation, occurring in <6% of metastatic colorectal cancer patients. Even more rare are the cutaneous recurrences at the peristomal site. Clinically, it is difficult to distinguish between metachronous cancer and cutaneous metastases. This paper reports a case of an elderly woman presenting with a slowly progressing peristomal cutaneous lesion 16 years after surgical resection for colorectal cancer. Core punch biopsy revealed a cutaneous localization of an intestinal type of adenocarcinoma. A surgical resection of the peristomal area was carried out whereby a new colostomy was created on the contralateral side. Definite histopathological examination showed a superficially located intestinal type adenocarcinoma with extensive pagetoid spread in the epidermal surface. In conclusion, it is important to remain alert and strive for early detection for cutaneous abnormalities following colorectal cancer.

Second Laparoscopic Colorectal Resection: Safety and Feasibility

BACKGROUND

As laparoscopic colorectal surgery continues increasing worldwide, the need of having a second laparoscopic colorectal resection (SLCR) might increase as well. Experience with this challenging procedure is scarce. The aim of this study was to evaluate the safety and feasibility of SLCR.

METHODS

A retrospective analysis of a prospectively collected database of patients undergoing colorectal surgery who needed an SLCR during the period 2008-2020 was performed. Demographics, operative variables, and postoperative outcomes were analyzed. A propensity score matching with a control population undergoing a first elective colorectal resection was performed.

RESULTS

A total of 1918 patients underwent colorectal surgery and 32 patients (1.7%) who required a SLCR were included for analysis; 17 (53.1%) were male, and the mean age was 71 (39 to 89) years. The median time between the first and second operations was 69 (6 to 230) months. At the second resection: The median operative time was 170 (90 to 380) minutes, there were 3 (9%) intraoperative complications and 2 (6%) conversions. Overall postoperative morbidity and major morbidity rates were 34% and 19%, respectively. Four patients (12.5%) required reoperation and 1 (3.1%) died of septic shock after an anastomotic leak. After propensity score matching, SLCR was more frequently performed by colorectal surgeons, and no differences in perioperative variables were observed compared with the control group.

CONCLUSIONS

SLCR can be safely performed without jeopardizing perioperative outcomes. Further studies are needed to confirm the benefits of the minimally invasive approach in colorectal second resection and to elucidate the long-term outcomes.

Prediction of the postoperative 90-day mortality after acute colorectal cancer surgery: development and temporal validation of the ACORCA model

PURPOSE

The aim of this study was to develop and validate a model to predict 90-day mortality after acute colorectal cancer surgery.

METHODS

The model was developed in all patients undergoing acute colorectal cancer surgery in 2014-2016 and validated in a patient group operated in 2017 in Denmark. The outcome was 90-day mortality. Tested predictor variables were age, sex, performance status, BMI, smoking, alcohol, education level, cohabitation status, tumour localization and primary surgical procedure. Variables were selected according to the smallest Akaike information criterion. The model was shrunken by bootstrapping. Discrimination was evaluated with a receiver operated characteristic curve, calibration with a calibration slope and the accuracy with a Brier score.

RESULTS

A total of 1450 patients were included for development of the model and 451 patients for validation. The 90-day mortality rate was 19% and 20%, respectively. Age, performance status, alcohol, smoking and primary surgical procedure were the final variables included in the model. Discrimination (AUC = 0.79), calibration (slope = 1.04, intercept = 0.04) and accuracy (brier score = 0.13) were good in the developed model. In the temporal validation, discrimination (AUC = 0.80) and accuracy (brier score = 0.13) were good, and calibration was acceptable (slope = 1.19, intercept = 0.52).

CONCLUSION

We developed prediction model for 90-day mortality after acute colorectal cancer surgery that may be a promising tool for surgeons to identify patients at risk of postoperative mortality.

Unexplained anemia: A case report of metachronous adenocarcinoma arising in the transverse colon following right hemicolectomy for a primary cecal carcinoma

Metachronous colonic carcinomas arise from months to years after the resection of the first or index primary colorectal cancer. They are not a result of tumor recurrence or metastasis and likely arise as a result of the field cancerization effect. This report presents the case of a 63-year-old male patient without family history of a colorectal cancer but had an index primary adenocarcinoma of the cecum (stage IIIC) five years ago that was treated with surgical resection and adjuvant radiotherapy and chemotherapy. He presented with fatigue and anemia of 6-month duration secondary to recurrent melena, and the specific cause of which remained obscure despite intensive diagnostic workup. Recurrence of a malignancy at the previous anastomosis site was ruled out. The patient continued to have recurrent and intermittent gastrointestinal bleeding until a nuclear red blood cell scan detected a bleeding spot in the epigastric region, which actually turned out to be a second primary carcinoma (stage I) arising from an adenoma in the transverse colon. The patient underwent a left colectomy with ileosigmoid anastomosis formation. During a two-month postoperative follow-up, the patient did not experience any episode of melena or anemia. Even though metachronous colon cancers rarely present with a recurrent and intermittent gastrointestinal bleeding with melena, an aggressive workup must be aimed at ruling out a second independent malignancy in patients who are in remission after an index primary colorectal cancer resection through hemicolectomy. Any neoteric lesion found on colonoscopy in such cases should be dealt with a higher degree of suspicion. Therefore, the need for surveillance colonoscopy as recommended by the National Comprehensive Cancer Network guidelines is imperative and should be practiced in resource-limited countries.

Laparoscopic hemicolectomy for a patient with situs inversus totalis and colorectal cancer

Situs inversus totalis is a congenital anatomic anomaly characterized by a complete inversion of thoracic and abdominal organs. We present a case of a 67 year-old patient diagnosed with situs inversus totals in his childhood who was referred for a two-month history of hematoquezia. Ascending colon cancer where found and he underwent a laparoscopic hemicolectomy with radical lymphadenectomy. An exhaustive preoperative study and a detailed planning of laparoscopic surgery including positions of operator and assistants and trocar sites have been performed to be aware of anatomic challenges. The operating time was 120 min and blood loss was minimal. Histologic examination showed a well-differentiated adenocarcinoma with serosal invasion and without lymph nodes metastasis (pT3N0). The patient was discharged on postoperative 6th day without complications. Laparoscopic surgery for colon cancer in patients with situs inversus totalis could be more difficult nevertheless a safe and feasible procedure should be performed successfully.

Metachronous advanced neoplasia after submucosal invasive colorectal cancer resection

Little is known about the incidence of metachronous advanced neoplasia (AN) following resection of submucosal invasive colorectal cancer (SM-CRC). Here, we aimed to assess the occurrence of metachronous AN following SM-CRC resection. We retrospectively reviewed consecutive patients who underwent SM-CRC resection at an academic medical center between 2005 and 2013. Among 343 patients, 250 (72.9%) underwent surgical resection or endoscopic resection followed by surgical resection and 93 (27.1%) underwent only endoscopic resection. During a median follow-up period of 61.5 months, the overall incidence of metachronous AN was 7.6%, and the cumulative incidence at 5 years was 6.1%. The cumulative incidence was significantly higher in the endoscopic resection group than in surgical resection group, in patients with colonic disease than in those with rectal disease, and in patients with synchronous AN than in those without. Multivariate analysis revealed that synchronous AN was the only significant risk factor for metachronous AN (HR 4.35; 95% CI 1.88–10.1). These findings imply that depending on synchronous AN, a surveillance protocol following SM-CRC resection can be changed for better detection of metachronous AN.

Does Colonic Diverticulosis Raise the Risk of Colorectal Adenoma in Patients with Colorectal Cancer?

Background

The aim of this study was to evaluate the risk of development of colorectal adenomas in patients with colorectal cancer (CRC) with and without colonic diverticulosis.

Methods

We performed a retrospective cohort study that included patients with CRC between 2008 and 2011. All patients underwent preoperative colonoscopic and barium enema examinations. Follow-up colonoscopic examinations were performed within 1 year and between 3 and 5 years postoperatively. The incidence of colorectal adenomas was compared based on the presence or absence of diverticulosis. Additionally, multivariate logistic regression analysis was performed to identify the factors independently associated with the development of synchronous and metachronous colorectal adenomas.

Results

Of the 168 patients with CRC included in the study, 55 showed colonic diverticulosis. Synchronous colorectal adenomas were more common in CRC patients with diverticulosis than in those without diverticulosis (P > 0.001). Multivariate regression analysis showed that colonic diverticulosis (odds ratio (OR) 3.874, 95% confidence interval (CI) 1.843–8.144, P > 0.001) and obesity (body mass index > 25.0 kg/m², OR 2.395, 95% CI 1.089–5.270, P = 0.030) were associated with an increased risk of synchronous colorectal adenomas. The presence of synchronous colorectal adenomas increased the risk of metachronous colorectal adenomas (OR 4.407, 95% CI 1.855–10.473, P > 0.001).

Conclusions

Colonic diverticulosis was associated with synchronous colorectal adenomas in patients with CRC, which is eventually increasing the risk of metachronous adenomas.

Various clinicopathological features of patients with metachronous colorectal cancer in relation to different diagnostic intervals

BACKGROUNDS

Clinicopathologic factors relating to developing metachronous colorectal cancer (CRC) have been reported. However, the effects of different diagnostic intervals on these risk factors required further analysis.

PATIENTS AND METHODS

This retrospective study comprised 14,481 patients diagnosed from January 1995 to December 2012. Metachronous CRC was defined as the occurrence of a second colorectal cancer at least 1 year post-operatively.

RESULTS

A total of 153 (1.06%) patients developed metachronous CRCs during the follow-up. Significantly higher rates of developing metachronous cancer occurred in male patients (1.2 vs 0.9%), patients with synchronous CRC (2.0 vs 1.0%), and patients with a positive family history of CRC (1.4 vs 0.9%). Pertaining to diagnostic intervals related to clinicopathological features, more severe staging was significant in the diagnostic interval between 2 and 3 years (35 vs 7.7%, 20.6%, 17.5%, P = .01) compared with other intervals. Male patients were more frequently detected to have CRC within 3 years compared with females (53.1 vs 29.1%, P = .005). For a diagnostic interval ≧ 5 years, a significantly higher rate of metachronous CRC located at the right colon was observed than that located at the left colon (36.6 vs 19.7%, p = 0.03).

CONCLUSIONS

We evinced that a diagnostic interval between 2 and 3 years was a key time for metachronous CRC diagnosis with worse staging distribution. Based on current findings, we recommend the stratification of metachronous CRCs into diagnostic intervals of 1-2, 2-3, and ≧ 3 years, as they exhibit significantly different characteristics.

Synchronous polypectomy during endoscopic diagnosis of colorectal cancer - is the risk of tumour implantation at the polypectomy site significant?

Background

Synchronous polypectomy in colonic malignancies is contentious due to the perceived risks of tumour implantation at polypectomy sites (PS). We assess the risks of tumour implantation after synchronous polypectomy.

Methods

An analysis of all endoscopies for cancer that were accompanied by synchronous polypectomies from 2005 to 2009 was performed. The incidence of metachronous colorectal cancers located at the same segment of a previous PS was the surrogate for tumour implantation. Data on patient demographics, tumour and polyp location(s) and follow-up outcomes were extracted. The rate of metachronous lesions at the same segment of a previous PS between patients who had all synchronous PS resected (Group A) and patients with PS left in-situ (Group B) were compared.

Results

Two hundred and eighty-four patients had synchronous polypectomy performed during their initial endoscopy for cancer. Three patients were lost to follow-up and, in the remaining 281 patients, 87 (31.0%) were in Group A while 194 (69%) were in Group B. Median age, gender, tumour location, tumour stage, and pathological characteristics were similar between both groups. 2 (0.7%) patients developed local recurrences. Six (2.1%) patients developed metachronous lesions, four of which were located at the same segment where synchronous polypectomy was previously performed. The rates of metachronous lesions at the PS in groups A and B were similar at 1.1% (1/87) and 1.5% (3/194), respectively (p = 0.795).

Conclusion

Malignant implantation after synchronous polypectomy in the setting of a newly diagnosed cancer remains unproven. Even if tumor implantation did occur, the incidence is likely low.

Metachronous Granular Cell Tumor of the Descending Colon

Granular cell tumors (GCTs) are uncommon tumors. They are believed to be neuronal in origin and are usually found in the head and/or neck area of the body. They have also been reported in various locations of the gastrointestinal (GI) system, usually discovered during routine screening colonoscopy. We report a case of GCT in a 58-year-old asymptomatic African American female as a metachronous tumor of a well-differentiated adenocarcinoma of the sigmoid colon, which was an incidental finding in screening colonoscopy. To our knowledge, this is the first case with GCT identified as a metachronous tumor following an adenocarcinoma of the colon.

Feasibility of Segmental Colectomy Followed by Endoscopic Surveillance as a Treatment Strategy for Colorectal Cancer Patients with Lynch Syndrome

BACKGROUND

Initial surgical procedures for colorectal cancer (CRC) patients with Lynch syndrome remain controversial. This study assessed the validity of segmental colectomy (SGC) followed by endoscopic surveillance as a treatment strategy for CRC patients with Lynch syndrome.

METHODS

Among consecutive patients who underwent surgery for primary CRC between April 1985 and December 2014, 49 patients were observed to have germline mutations in a mismatch repair gene, and 38 patients who underwent SGC followed by periodic endoscopic surveillance at our institution were evaluated for metachronous CRC, need for secondary surgery, and the details of endoscopic surveillance.

RESULTS

Of the 38 patients who underwent SGC followed by periodic endoscopic surveillance at our institution, 6 (15.8%) patients showed metachronous CRC, 3 (7.9%) patients underwent endoscopic resection, and the other 3 patients (7.9%) underwent secondary surgery. The dispersion of the endoscopic surveillance interval was significantly greater in patients with metachronous CRC (364 ± 332.9 days) than in those without metachronous CRC (370 ± 129.7 days; p < 0.001).

CONCLUSIONS

SGC followed by annual endoscopic surveillance was feasible as a treatment strategy for CRC patients with Lynch syndrome, because the incidence of metachronous CRC and the need for secondary surgery were low. Annual and periodic endoscopic surveillance might be essential for early detection of metachronous CRC and prevention of secondary surgery because of metachronous CRC in CRC patients with Lynch syndrome after SGC.

Surgical treatment of multiple sporadic colorectal carcinoma

Aim: Many aspects of the surgical management of multiple sporadic colorectal cancer syndrome, either synchronous and metachronous, remain to be cleared, in particular the prognostic influence of the extent of surgical resection. Method: A retrospective review was performed of patients diagnosed with multiple colorectal cancer from 1982 to May 2010. Clinical and pathologic data were collected and reviewed. Survival analysis was performed. Results: We identified 23 patients with multiple sporadic colorectal cancers, of which 8 had synchronous (SC) and 15 metachronous cancers (MC). Of the MC patients, 2 (13%) had the second cancer within 2 years, 4 (27%) in the time period of 2-5 years and 9 (60%) after 5 years. Twenty-one patients underwent multiple segmental resections; 2 patients underwent subtotal colectomy. The 5-year overall survival rate of SC and MC patients was 100% and 87% (p<0.001) respectively. The 5-year overall survival rate of multiple segmental resection patients and subtotal colectomy was 94% and 75% (p=0.655) respectively. Conclusion: Either synchronous and metachronous MSCRC patients showed good prognosis independently from to the extent of resection. Our results support a less aggressive biological behaviour allowing a more conservative management. Multiple segmental colorectal resections seem appropriate from an oncologic point of view in MSCRC patients. (www.actabiomedica.it)

Risk of subsequent primary malignancies among patients with prior colorectal cancer: a population-based cohort study

BACKGROUND

The site-distribution pattern and relative risk of subsequent primary malignancies (SPMs) in colorectal cancer (CRC) patients remains to be determined.

MATERIALS AND METHODS

A population-based cohort of 288,390 CRC patients diagnosed between 1973 and 2012 from the Surveillance, Epidemiology, and End Results database was retrospectively reviewed. Standardized incidence ratios were calculated to estimate the relative risk for SPMs.

RESULTS

The overall risk of SPMs increased in CRC patients (standardized incidence ratio 1.02) in the first 5 years after CRC diagnosis compared with that in the general population, and was negatively related to age at diagnosis. Risk increased significantly for cancers of the small intestine, ureter, colorectum, renal pelvis, endocrine system, and stomach, and decreased significantly for cancers of the gallbladder, liver, myeloma, and brain, as well as lymphoma. Patients with different prior CRC subsites showed specific sites at high risk of SPM. Prior right-sided colon cancer was associated with cancers of the small intestine, ureter, renal pelvis, thyroid, stomach, pancreas, and breast and prior left-sided colon cancer associated with secondary CRC, whereas rectal cancer was associated with cancers of the vagina, urinary bladder, and lung.

CONCLUSION

Risk of SPMs increases in CRC survivors, especially in the first 5 years after prior diagnosis. Intensive surveillance should be advocated among young patients, with specific attention to the small intestine, colorectum, renal pelvis, and ureter. The common sites at high risk of SPM originate from the embryonic endoderm. Genetic susceptibility may act as the main mechanism underlying the risk of multiple cancers.

Clinicopathological features and surgical options for synchronous colorectal cancer

This study was conducted to investigate the clinicopathological features of synchronous cancers and treatment options according to their locations.Records of 8368 patients with colorectal cancer treated at our center between July 2003 and December 2010 were analyzed retrospectively. All synchronous colorectal cancer patients who underwent surgical treatment were included.Synchronous cancers were identified in 217 patients (2.6%). Seventy-nine patients underwent either total colectomy, subtotal colectomy, or total proctocolectomy; 116 underwent 1 regional resection, including local excision; and 22 underwent 2 regional resections. The mean age was 62 years, slightly higher than that for the single-cancer patients. Synchronous cancers were more common in male patients, more frequently located in the left colon, had more microsatellite instability-high status, and showed more advanced stage than single cancer. Extensive resection was mainly performed for synchronous cancers located in both the right and left colon. Two regional resections were performed for cancers in the right colon and rectum. There were no differences in complication rates or the occurrence of metachronous cancer between the 2-region resection and extensive resection groups. Eight years postoperatively, the mean number of daily bowel movements for these 2 groups were 1.9 and 4.3, respectively.We found that synchronous cancer was different from single cancer in terms of age, gender, location, and pathologic features. Synchronous colorectal cancer requires different treatment strategy according to the distribution of lesions. Comparison between the 2 regional resections and extensive resection approaches suggests that 2 regional resections are preferable.

Dual malignancy in adolescence: A rare case report of metachronous papillary carcinoma of thyroid following dysgerminoma of ovary

Dual malignancy is rare in adolescents. Dual malignancy with the second malignancy of thyroid is rare. No association has been reported between dysgerminoma of ovary and carcinoma thyroid in medical literature. Despite a thorough PubMed search (key words — Papillary carcinoma of thyroid, metachronous, dysgerminoma ovary), we were unable to find a previous reported case of metachronous papillary carcinoma of thyroid (PTC) following dysgerminoma of the ovary. After surgery, the patient is being regularly followed up for recurrence/development of new primary. We report this unusual and rare case in a 17-year-old female patient.

Tumor size is an independent risk predictor for metachronous colorectal cancer

Non-hereditary colorectal cancer (CRC) patients are at higher risk of developing independent metachronous CRC than cancer-naïve individuals, but the reason is unknown. We studied metachronous CRC risk factors among one thousand five Japanese CRC patients who underwent surgery for CRC. Relative hazard risk of clinical and pathological features was assessed by univariate and multivariate Cox's proportional hazard regression analysis. Observed metachronous CRC incidence was also compared with the expected cancer incidence of the general population in Japan. Twenty-seven metachronous CRCs developed in 24 patients (2.4%) during a follow-up period of 3,676 person-years. Multivariate analysis revealed two factors associated with a high metachronous CRC risk: synchronous CRC (HR = 6.13; p = 1.3x10(-4)) and tumor size ≥ 6.5 cm (HR = 4.34; p = 1x10(-3)). Patients with either synchronous or large solitary tumors exhibited a higher risk for metachronous CRC than patients with solitary small tumors (HR = 7.3; p = 4.3x10(-6)) and that the general Japanese population (SIR = 7.01; p = 3.5x10(-9)), while patients with solitary small tumors did not (SIR = 1.07; p = 0.8). If patients younger than 60 years were excluded, the observations remained unchanged, with tumor size becoming stronger predictor (HR = 5.67; p = 1.7x10(-4)) than the presence of synchronous CRC (HR = 5.34; p = 9.6x10(-4)). Our novel finding that primary tumor size is a strong independent risk factor for metachronous CRC increases the sensitivity of prediction more than twice the presence of synchronous CRC. Our data provides new insights to assess the risk for metachronous lesions that should improve the surveillance regimen for CRC.

Feasibility and safety of laparoscopic surgery for metachronous colorectal cancer

PURPOSE

This study assessed the feasibility and safety of laparoscopic surgery for metachronous colorectal cancer in patients who had previously undergone surgery for primary colorectal cancer.

METHODS

Of the 52 patients who underwent curative resection for metachronous colorectal cancer from August 2004 to April 2013, 26 each underwent laparoscopic and open surgery. Their clinical characteristics and surgical and postoperative outcomes were compared.

RESULTS

The percentage of patients who underwent previous open surgery was significantly higher in the open group than in the laparoscopic group (92.3 vs. 65.4 %). The body mass index was higher in the laparoscopic group than in the open group (23.8 vs. 21.1 kg/m(2)), and the amount of blood loss was significantly smaller in the laparoscopic than in the open group (30 vs. 195 ml); however, the mean operative time did not differ significantly. The time to first flatus (1 vs. 3 days) and first stool (2 vs. 3.5 days), as well as the length of postoperative hospital stay (10 vs. 16 days), was significantly shorter in the laparoscopic group than in the open group, although the rates of postoperative complications did not differ (15.4 vs. 23.1 %).

CONCLUSIONS

Laparoscopic surgery for metachronous colorectal cancer shows short-term benefits compared with open surgery and should be considered as a treatment option in these patients.

Metachronous carcinomas in colorectum and its clinicopathological significance

PURPOSE

The study was designed to examine the significance of colorectal metachronous carcinoma in a large cohort of patients.

METHODS

Over a mean follow-up period of 10 years, the clinicopathological features, microsatellite instability (MSI) and clinical follow-up of 56 patients with metachronous colorectal carcinoma were analysed.

RESULTS

The prevalence of metachronous colorectal carcinoma was 2.1 %. The metachronous colorectal carcinomas appeared between 7 and 246 months (mean = 66 months) after surgical resection of the index colorectal carcinomas. Thirty-six per cent (n = 20) of the metachronous carcinoma occurred more than 5 years after the operation of the index carcinoma. Of the 56 patients, 20 % (n = 11) of the metachronous colorectal carcinomas were mucinous adenocarcinoma. Cancers detected in the secondary operations (metachronous colorectal carcinomas), when compared with the primary index cancers, were smaller, showed higher proportions of mucinous adenocarcinoma and more often located in the proximal colon. Patients with metachronous colorectal cancers had higher prevalence of mucinous adenocarcinoma, loss of staining for MSI markers and better survival rates than other patients with colorectal cancers.

CONCLUSIONS

Patients with metachronous colorectal carcinomas have characteristic features, and attention to these features is important for better management of this group of cancer.

High constant incidence of second primary colorectal cancer

Patients who had a colorectal cancer have a 1.5- to 2-fold excess risk of a second colorectal cancer as compared to the general population, the excess being higher at younger age at diagnosis. To further investigate the risk and the age-relation of the incidence of second primary colorectal cancer, we considered 9,389 first colon and rectal cancers registered in the Vaud Cancer Registry, Switzerland, between 1974 and 2008, and followed-up to the end of 2008 for a total of 44,113 person-years. There were 136 second colorectal cancers versus 90.5 expected, corresponding to a standardized incidence ratio (SIR) of 1.5 (95% confidence interval, CI, 1.3-1.8). The SIRs were not heterogeneous between men and women, and in strata of calendar year at diagnosis, duration of follow-up, and subsite. However, the SIR was 7.5 (95% CI 4.2-12.4) for subjects diagnosed below age 50 and declined thereafter to reach 1.0 (95% CI 0.6-1.6) at age 80 or over. Consequently, the incidence of second primary colorectal cancer was stable, and exceedingly high, around 300-400/100,000 between age 30-39 and 70 or over. This age pattern is consistent with the existence of a single mutational event in a population of highly susceptible individuals.

The incidence and risk factors of metachronous colorectal cancer: an indication for follow-up

BACKGROUND

Patients with colorectal cancer are at risk for developing metachronous colorectal cancer. The purpose of posttreatment surveillance is to detect and remove premalignant lesions to prevent metachronous colorectal cancer.

OBJECTIVE

The aim of this study was to investigate the incidence of and predictive factors for metachronous colorectal cancer in patients with newly diagnosed colorectal cancer.

DESIGN AND PATIENTS

The data on all patients with newly diagnosed colorectal cancer between 1995 and 2006 were obtained from the Rotterdam Cancer Registry in The Netherlands and studied for metachronous colorectal cancer.

MAIN OUTCOME MEASURES

The annual incidence rate and the standardized incidence ratios were calculated.

RESULTS

In total, colorectal cancer was diagnosed in 10,283 patients; there were 39,974 person-years of follow-up. The mean annual incidence rate of metachronous colorectal cancer was 314/100,000 person-years at risk during 10 years of follow-up, corresponding with a mean annual incidence of 0.3% and a cumulative incidence of 1.1% at 3 years, 2.0% at 6 years, and 3.1% at 10 years. The incidence of metachronous colorectal cancer after resection of a first colorectal cancer is significantly higher than the incidence of colorectal cancer in an age- and sex-matched general population (standardized incidence ratio 1.3, 95% CI 1.1-1.5). This difference is especially seen during the first 3 years after first colorectal cancer diagnosis (standardized incidence ratio 1.4, 95% CI 1.1-1.8). The presence of synchronous colorectal cancer was the only significant risk factor for developing metachronous colorectal cancer (relative risk 13.9, 95% CI 4.7-41.0).

CONCLUSIONS

Despite the availability of colonoscopy, metachronous colorectal cancer is still seen during follow-up in patients with colorectal cancer; the highest risk is during the first 3 years after initial diagnosis. For this reason, a follow-up colonoscopy is useful at a short-term interval after colorectal cancer diagnosis. The presence of synchronous colorectal cancer at the time of first colorectal cancer diagnosis is the only predictive risk factor for developing metachronous colorectal cancer. Tailored surveillance programs may be considered in patients with a diagnosis of synchronous tumors.

Metachronous double cancer after curative resection for pancreatic adenocarcinoma: report of four cases

We experienced four cases of metachronous double cancer after curative resection for pancreatic adenocarcinoma without the background of intraductal papillary mucinous neoplasm. Case 1, a 67-year-old Japanese female developed tongue cancer 53 months after a pylorus-preserving Whipple resection for pancreatic head adenocarcinoma. Case 2, a 66-year-old female developed multiple breast cancers 52 months after a pylorus-preserving pancreaticoduodenectomy for pancreatic head adenocarcinoma. Case 3, a 59-year-old male developed an adenocarcinoma in the remnant pancreatic head 63 months after a distal pancreatectomy for pancreatic body cancer. Case 4, a 68-year-old male developed lung cancer 92 months after a Whipple procedure for pancreatic head adenocarcinoma. Gemcitabine was administered to three patients as adjuvant chemotherapy at an average administrated dose of 38,199 mg per body surface area. Since primary pancreatic ductal adenocarcinoma is aggressive and always associated with a devastating outcome, metachronous double cancer is scarcely seen. All four cases received curative-intent surgery for each metachronous cancer and were alive for at least 20 months.

Double primary malignancies associated with colon cancer in patients with situs inversus totalis: two case reports

Situs inversus totalis (SIT) is not itself a premalignant condition, however, rare synchronous or metachronous multiple primary malignancies have been reported. Herein we present a case of synchronous transverse and sigmoid colon cancers and a case of metachronous rectosigmoid colon and gastric cancers in patients with SIT.A 66-year-old male with SIT was referred for a two-month history of hematochezia. Synchronous colonic tumors were found on the proximal transverse and sigmoid colon. The patient underwent open total colectomy and was discharged without incident. A 71-year-old female with rectosigmoid colon cancer and SIT underwent laparoscopy-assisted low anterior resection. Fourteen months after the surgery, the patient developed a single hepatic metastasis and underwent hepatic segmentectomy (S6). Forty-six months after laparoscopy-assisted low anterior resection, the patient developed metachronous early gastric cancer on the antrum and underwent radical subtotal gastrectomy with gastroduodenostomy. The patient is doing well without recurrence for 28 months.

Laparoscopic salvage surgery for recurrent and metachronous colorectal cancer: 15 years' experience in a single center

BACKGROUND

Laparoscopic salvage surgery for colorectal cancer is a novel but technically challenging option for surgeons. The aim of this study was to evaluate the feasibility and safety of laparoscopic surgery in patients with recurrent or metachronous colorectal cancer in comparison with an open approach.

METHODS

The data used in this study were obtained from databases, the data of which were collected prospectively from January 1996 to February 2010. Data pertaining to patients, operations, and short-term outcomes were analyzed and compared between open and laparoscopic salvage groups.

RESULTS

Among the 3,425 patients studied, colorectal cancer recurred in 565 patients (16.5%) and 41 patients had colorectal salvage operations. Twenty-six patients with recurrence underwent open surgery and 15 cases underwent laparoscopic surgery. The short-term outcomes of the laparoscopic group were comparable with those of the open surgery group or were partly favorable. The five-year disease-free interval and overall survival of recurrent cancer patients were not significantly different from those of the open patients. Metachronous colorectal cancer occurred in 13 patients (0.38%), 5 of whom had open surgery and 6 had laparoscopic salvage. The only significant difference between the groups was a shorter operating time for the laparoscopic group. Late in the study, four patients in the laparoscopic recurrent group and one patient in the metachronous group were converted to open surgery.

CONCLUSIONS

Laparoscopic surgery yielded short-term outcomes that were comparable to those of conventional open surgery, in both recurrent and metachronous colorectal cancer patients. Thus, minimally invasive salvage approaches should be considered as a treatment option for the recurrent and the metachronous colorectal cancer patient.

Estimating the unknown parameters of the natural history of metachronous colorectal cancer using discrete-event simulation

OBJECTIVES

Some aspects of the natural history of metachronous colorectal cancer (MCRC), such as the rate of progression from adenomatous polyp to MCRC, are unknown. The objective of this study is to estimate a set of parameters revealing some of these unknown characteristics of MCRC.

METHODS

The authors developed a computer simulation model that mimics the progression of MCRC for a 5-year period following the treatment of primary colorectal cancer (CRC). They obtained the inputs of the simulation model using longitudinal data for 284 CRC patients from the Mayo Clinic, Rochester.

RESULTS

Five-year MCRC incidence and all-cause mortality were 7.4% and 12.7% in the patient cohort, respectively. Statistical analysis showed that 5-year MCRC incidence was associated with gender (P = 0.05), whereas both all-cause and CRC-related mortalities were associated with age (P < 0.001 and P = 0.01). Estimated annual probabilities of progression from adenomatous polyp to MCRC and from MCRC to metastatic MCRC were 0.14 and 0.28, respectively. Annual probabilities of mortality after MCRC and metastatic MCRC treatments were estimated to be 0.06 and 0.26, respectively. The estimated annual probability of mortality due to undetected MCRC was 0.16.

CONCLUSIONS

The results imply that MCRC, especially in women, may be more common than suggested by previous studies. In addition, statistics derived from the clinical data and results of the simulation model indicate that gender and age affect the progression of MCRC.

Second primary colorectal cancers (SPCRCs): experiences from a large Australian Cancer Registry

BACKGROUND

We examined the rate of second primary colorectal cancer (SPCRC) in a cohort of 29 471 patients first diagnosed with colorectal cancer (CRC) from 1987 to 1996, in New South Wales (NSW), Australia.

METHODS

The 5-year age group, date and site of first and subsequent CRC diagnoses as well as death dates were obtained from the NSW Central Cancer Registry. The time to SPCRC and standardised incidence ratios (SIRs) were generated.

RESULTS

Six hundred and sixty patients (2.1%) developed SPCRCs and the cumulative incidence at 18 years was 5.5%, 95% confidence interval (CI) 4.9% to 6.3%. The risk of SPCRC was increased in patients with a CRC history compared with the general population (SIR = 1.5, 95% CI 1.4-1.6) and inversely related to age at first diagnosis (30-49 years, SIR = 5.1, 95% CI 3.6-7.1 versus >/=80 years, SIR = 1.1, 95% CI 0.9-1.4). The excess absolute risk of SPCRC was greater for females aged 50-69 years at first diagnosis than for males in the same age group. SPCRC was also increased in individuals with right-sided first primaries (SIR = 2.0, 95% CI 1.6-2.4).

CONCLUSIONS

The SPCRC rate was increased during the first 5 years after first diagnosis but remained increased for up to 10 years in females, in patients with right-sided cancers and in patients <60 years at first diagnosis. These findings support active surveillance up to 10 years in these risk groups.

Clinicopathologic characteristics of metachronous colorectal cancer: an analysis of 31 cases

AIM: To investigate the clinicopathologic characteristics of metachronous colorectal cancer and to facilitate its diagnosis and treatment.

METHODS: Thirty-one cases diagnosed with metachronous colorectal cancer were treated and closely followed up. Clinical records such as the occurrence, distribution, and stage of index and secondary tumors were retrospectively reviewed. The prognosis after surgery was also analyzed.

RESULTS: Secondary tumors occurred in all 31 patients in an average of 5.1 years after the diagnosis of their index colorectal cancers. Three cases had a third tumor after an average of 3.8 years, and then two of them had a fourth tumor after an average interval of 3.5 years. Of the 31 cases, 45.2 percent of them had synchronous adenoma. The majority of index tumors (59.5%) were located in the rectum or sigmoid colon. Most of the secondary tumors were similar to or better than their index tumors in the levels of differentiation and pathological grades. An average survival of 8.3 years was achieved after the radical operation of the index tumor. The 5-year survival rate reached 84.8%.

CONCLUSION: In patients with metachronous colorectal cancer, the primary tumor is more commonly located in the rectum or sigmoid colon. With the occurrence of subsequent tumor, interval time was shortened gradually. An intensive periodic checkup after operation is strongly recommended for improvement of prognosis.

Low Local Recurrence Rates after Rectal Cancer Resection with Limited Use of Preoperative Radiotherapy

Background:

Local recurrence rates after curative rectal resection for rectal cancer have decreased after introduction of TME. In order to achieve even further reduction in local recurrence rates, several hospitals increase the use of preoperative radiotherapy. Thus, radiotherapy-related side effects will increase. The aim of the study was to evaluate the results of the TME-technique with minimal use of radiotherapy.

Materials and Methods:

A prospective observational study from 1993 to 2000 of 137 consecutive patients treated for rectal cancer at the Department of Surgery, Nordland Hospital HF, Bodø, Norway.

Results:

115 patients underwent curative resections (84%). Eight patients (6.4 %) received peri-operative radiotherapy: three preoperatively (2.4%) because of clinically fixed tumours and five patients (4%) postoperatively; four with pR1-resections and one patient after perforation of the rectum. The local recurrence rate was 3.4 % with an observation time of 5 years. The total survival rate was 74% in curative group. In 22 patients the treatment was palliative. Only one of these patient survived 5 years.

Conclusion:

With TME-technique it is possible to achieve low recurrence rates and high survival rates with a high curative rate with minimal use of additional radiotherapy.