The seventh edition of the TNM Classification of Malignant Tumors contains several new and modified component classifications. The purpose of this communication was to briefly summarize these changes.
The seventh edition of the TNM Classification of Malignant Tumors contains several new and modified component classifications. The purpose of this communication was to briefly summarize these changes.
The vermiform appendix is the primary site of several distinctive benign and malignant neoplasms. Some can produce the clinical syndrome of pseudomyxoma peritonei (PMP). A consensus on their ...terminology was reached by an international panel of pathologists and clinicians working under the auspices of the Peritoneal Surface Oncology Group International (PSOGI), and this review discusses the application of the PSOGI classification to routine reporting. We discuss diagnosis and differential diagnosis together with implications for patient management, covering low‐grade appendiceal mucinous neoplasms, high‐grade appendiceal mucinous neoplasms, serrated polyps, adenomas and adenocarcinomas. We do not cover goblet cell tumours or neuroendocrine neoplasms in this paper.
Pseudomyxoma peritonei (PMP) is a complex disease with unique biological behavior that usually arises from appendiceal mucinous neoplasia. The classification of PMP and its primary appendiceal ...neoplasia is contentious, and an international modified Delphi consensus process was instigated to address terminology and definitions. A classification of mucinous appendiceal neoplasia was developed, and it was agreed that "mucinous adenocarcinoma" should be reserved for lesions with infiltrative invasion. The term "low-grade appendiceal mucinous neoplasm" was supported and it was agreed that "cystadenoma" should no longer be recommended. A new term of "high-grade appendiceal mucinous neoplasm" was proposed for lesions without infiltrative invasion but with high-grade cytologic atypia. Serrated polyp with or without dysplasia was preferred for tumors with serrated features confined to the mucosa with an intact muscularis mucosae. Consensus was achieved on the pathologic classification of PMP, defined as the intraperitoneal accumulation of mucus due to mucinous neoplasia characterized by the redistribution phenomenon. Three categories of PMP were agreed-low grade, high grade, and high grade with signet ring cells. Acellular mucin should be classified separately. It was agreed that low-grade and high-grade mucinous carcinoma peritonei should be considered synonymous with disseminated peritoneal adenomucinosis and peritoneal mucinous carcinomatosis, respectively. A checklist for the pathologic reporting of PMP and appendiceal mucinous neoplasms was also developed. By adopting the classifications and definitions that were agreed, different centers will be able to use uniform terminology that will allow meaningful comparison of their results.
Gastrointestinal (GI) stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are the most common mesenchymal tumors of the GI tract. In this study, we analyzed 1869 ...cases originally classified as smooth muscle tumors of the stomach and found that 1765 (94%) of these were GISTs. The GISTs had a slight male predominance (55%) with a median age of 63 years. Only 2.7% of tumors occurred before the age of 21 years and 9.1% before the age of 40 years. The tumors varied from 0.5 to 44 cm (median, 6.0 cm) and most commonly presented with GI bleeding; 12% were incidentally detected. Several histologic variants were recognized among the spindle cell tumors (sclerosing, palisaded-vacuolated, hypercellular, and sarcomatous) and of epithelioid tumors (sclerosing, dyscohesive, hypercellular, and sarcomatous). Outcome was strongly dependent on tumor size and mitotic activity. Only 2% to 3% of tumors <10 cm and <5 mitoses/50 HPFs metastasized, whereas 86% of tumors >10 cm and >5 mitoses/50 HPFs metastasized. However, tumors >10 cm with mitotic activity <5/50 HPFs and those <5 cm with mitoses >5/50 HPFs had a relatively low metastatic rate (11% and 15%). A small number of patients survived intra-abdominal metastasis up to over 20 years. Tumor location in fundus or gastroesophageal junction, coagulative necrosis, ulceration, and mucosal invasion were unfavorable factors (P <0.001), whereas tumor location in antrum was favorable (P <0.001). KIT expression was detected in 91% of the cases, CD34 in 82%, smooth muscle actin in 18%, and desmin in 5%; the latter two were favorable (P <0.001). KIT exon 11 mutations were detected in 119 cases; patients with point mutations fared better than those with deletions (P <0.01). PDGFRA exon 18 mutations (total 86 cases) were common in epithelioid GISTs and most commonly represented a D842V point mutation; none of these was prognostically significant. The above results may be helpful for setting the criteria for adjuvant treatment such as Gleevec.
The Union for International Cancer Control's (UICC) TNM classification is a globally accepted system to describe the anatomic extent of malignant tumors. Since its development seventy years ago, the ...TNM classification has undergone significant revisions to reflect the current understanding of extent of disease and its role in prognosis. To ensure that revisions are evidence‐based, the UICC implemented a process for continuous improvement of the TNM classification that included a formalized system for submitting proposals for revisions directly to the UICC and an annual review of the scientific literature on staging that assessed, criticized or made suggestions for changes. The process involves review of the proposals and literature by a group of international, multidisciplinary Expert Panels. The process has been in place for 10 years and informed the development of the 7th edition of the TNM classification published in 2009. The purpose of this article is to provide a description of the annual literature review process, including the search strategy, article selection process and the roles and requirements of the Expert Panels in the review of the literature. Since 2002, 147 Expert Panel members in 11 cancer sites have reviewed over 770 articles. The results of the annual literature reviews, Expert Panel feedback and documentation and dissemination of results are described.
What's new?
The Union for International Cancer Control's TNM classification undergoes periodic revisions to incorporate current knowledge of anatomic extent of disease and its relationship with patient management and prognosis. This article describes the results of an annual literature review process that was implemented in 2002 to inform revisions to the classification. Since that time, more than 770 articles have been reviewed, with the number of articles reviewed increasing over time, reflecting growing research interest in cancer staging and new developments in cancer diagnosis. The report suggests that the literature review process has enhanced recent changes to the TNM classification.
Gastrointestinal stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, most commonly occur sporadically, but there seems to be some increased tendency for these ...tumors to develop in patients with neurofibromatosis 1 (NF1). The clinicopathologic profile, KIT, and PDGFRA mutation status and long-term prognosis of patients with GIST in NF1 are incompletely characterized. In this study, we analyzed 45 patients who had NF1 and GIST. There were 26 females and 19 males with a median age of 49 years (10 years lower than the median age of GIST patients in general). A great majority of tumors occurred in the jejunum or ileum, with multiple tumors occurring in 28 cases. Ten patients had a duodenal and one had a gastric GIST. The most common presentations were gastrointestinal bleeding and anemia, and many patients had intermittent bleeding over several years. The majority of the tumors were small and mitotically inactive; only 7 had mitotic activity >5/50 HPFs and 15 tumors were >5 cm. Associated Cajal cell hyperplasia was common. One patient had an intraabdominal peri-intestinal neurofibroma. Five of 35 patients with follow-up died of metastatic disease; all of these had a tumor >5 cm, mitotic rate >5/50 HPFs, or both; three of these tumors were located in the duodenum. The presence of multiple small tumors was not associated with progressive disease. Most patients with long-term follow-up enjoyed a good prognosis; 2 died of other NF1-associated tumors (malignant peripheral nerve sheath tumors, brain tumor). None of the 16 tumors from 15 patients had a KIT exon 9, 11, 13, or 17 or PDGFRA exon 12 or 18 mutation as is typically seen in sporadic GISTs, indicating that GISTs in NF1 patients have a different pathogenesis than sporadic GISTs.
Since the introduction of the TNM residual tumor (R) classification, the involvement of resection margins has been defined either as a microscopic (R1) or a macroscopic (R2) demonstration of tumor ...directly at the resection margin ("tumor transected").
The recognition of the importance of the circumferential resection margin (CRM) in patients with rectal cancer patients raises the need for an alternative definition of resection margin involvement, namely, the importance of delineating tumor with a minimal distance from the CRM of <or=1 mm (CRM-positive) from tumor directly at the resection margin. The different use of both definitions of resection margin involvement prevents valid comparisons between reports on treatment results.
To avoid confusion by different definitions, the authors proposed including the minimal distance between tumor and resection margin into the current R classification.
By using the proposed expanded classification, comparisons of new data with previous publications will be possible.
Gastrointestinal (GI) stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are the most common mesenchymal tumors of the GI tract. This study analyzed 1091 tumors ...originally classified as smooth muscle tumors of the small intestine (including jejunum or ileum and excluding duodenum), and found that 906 (83%) of these were GISTs. The GIST patients had 55:45 male-to-female ratio with a median age of 59 years (range, 13-94 years). Only 0.6% of tumors occurred before the age of 21 years and 13.6% before the age of 40 years. The tumors varied from 0.3 to 40 cm (median, 7.0 cm) and most commonly presented with GI bleeding or acute abdomen; 18% were incidentally detected. Histologically, the tumors were relatively monotypic with spindle cell (86%), epithelioid (5%), or mixed patterns (9%). Skeinoid fibers were present in 44% of cases, and their presence was associated with a favorable course. Most epithelioid tumors were malignant, and this morphology sometimes emerged from less cellular and less mitotically active spindle cell tumors, suggesting that it represented a transformation. KIT was immunohistochemically detected in 98%, CD34 in 40%, smooth muscle actin in 34%, desmin in 0.2%, and S-100 protein in 14% of the tumors tested. Outcome was strongly dependent on tumor size and mitotic activity, with an overall 39% tumor-related mortality, twice that for gastric GISTs. Only <3% of tumors <5 cm and < or = 5 mitoses/50 HPF metastasized, whereas 86% of tumors >10 cm and >5 mitoses/50 HPF metastasized. In stark contrast to corresponding gastric tumors, tumors >10 cm with mitotic activity < or = 5/50 HPF and those < or = 5 cm with mitoses >5/50 HPF had a high metastatic rate (>50%); tumors >5 cm < or = 10 cm with low mitotic rate had a 24% metastatic rate. The median survival times of patients with low mitotic rate tumors who died of disease decreased by increasing tumor size. KIT exon 11 mutations were detected in 90 cases, exon 9 mutation in 17 cases, and exon 17 mutation in 1 case; the presence of mutation or mutation type was not prognostically significant. There were no PDGFRA exon 12 or 8 mutations. Systematic data on prognosis of small intestinal GISTs of various size and mitotic activity categories can be helpful in management and surveillance of patients with these tumors.
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