Colorectal mesenchymal tumors - from smooth muscle tumors to stromal tumors

Colorectal mesenchymal tumors are rare. Therefore, distinguishing between gastrointestinal stromal (GIST) and smooth muscle tumors is important. This study aimed to delineate the immunophenotype and prognostic factors of 75 colorectal mesenchymal tumors. Fifty-three GIST and 22 smooth muscle tumor specimens were included from 1986 to 2007. Forty of 53 GIST were initially diagnosed as smooth muscle tumors and re-diagnosed as CD117 (+) GIST. Immunohistochemical studies were performed with antibodies of CD117, CD34, smooth muscle actin (SMA), desmin, S-100, Ki-67 and PCNA for clinicopathologic and prognostic correlation. In comparison, colorectal GIST exhibited a larger tumor size (P<0.001), higher mitotic count (P<0.001), higher cellularity (P<0.001), less spindle cell type (P=0.004), higher nuclear pleomorphism (P=0.004), and a higher NIH risk (P<0.001) than that of smooth muscle tumors. Positive immunoreactivities of GIST to a panel of antibodies were 88.6% to CD34, 28.3% to SMA, 1.8% to S-100 and 15.1% to desmin. For 75 mesenchymal tumors, survival analyses revealed that older patients (P=0.006), with a large tumor size (P<0.001), high mitotic count (P<0.001), increased NIH risk (P<0.001), non-spindle cell type (P<0.001), high cellularity (P=0.015), high cell pleomorphism (P<0.001), positive Ki-67 (P<0.001), high PCNA (P<0.001) and GIST (P=0.001) had a shorter disease-free survival than that of comparative groups. When the analyses concentrated on 53 GIST, the cell type and cellularity were no longer viable prognostic factors. The tumor mitotic count was the only independent prognostic factor for either mesenchymal tumors or GIST. In conclusion, GIST exhibited heterogeneous characteristics and was significantly larger, more mitotic and a poorer prognostic factor than smooth muscle tumor. The mitotic count is still the most valuable prognostic factor for colorectal mesenchymal tumors after KIT.     

Brain tumors

Brain tumors generally arise as the culmination of a multistep process that involves a variety of genetic abnormalities. Theoretically, replacement of abnormal genes with normal genes is essential to brain tumor treatment. However, it is very difficult to replace all damaged genes. Currently, most clinical protocols for gene therapy in brain tumors include transfer of a gene which can induce tumor cells to die or which can enhance the environment to generate a systemic immune response against the tumor. The former strategy includes suicide gene therapies, tumor suppressor gene therapy and oncolytic virus therapy. The latter adopts immunogene therapy. In this report, we also focus on other gene therapies, such as therapies to control the cell cycle or apoptosis, and promote antiangiogenesis. Gene therapy is generally accepted to be rather safe in recent years. In fact, the current single-gene therapies for brain tumor are limited and probably restricted to a few tumors. Several agents with different mechanisms of action would be necessary to kill heterogenously mixed tumor cells. Further molecular techniques and basic studies may overcome the malignancy of cancers.     

Prolactin-secreting tumors

A case of galactorrhea induced by hyperprolactinemia has been reported. This patient had bronchogenic carcinoma, undifferentiated, spindle-cell-type, and underwent a pneumonectomy followed by postoperative irradiation of the mediastinum. The initial surgical resection, followed by irradiation, returned the abnormal levels of prolactin secretion to normal. Although subsequent determinations could not be made, this case supports evidence from earlier reports that galactorrhea-induced hyperprolactinemia may occur concomitantly as a paraneoplastic syndrome with this rare form of carcinoma.     

Desmoid tumors

Opinion statement Because of the wide variety of anatomic locations and patient factors, there is no one treatment that is appropriate for all desmoid tumors. The type of treatment depends on tumor characteristics and location, as well as patient characteristics and preferences. Desmoid tumors can be persistent and frustrating to manage because no one treatment modality offers a high likelihood of remission. Multiple modalities may be necessary in some patients. Although mortality is rare and is usually due to local complications, significant disability or morbidity can result from desmoid tumors, their treatment, and complications arising from treatment. The entire clinical picture and the patient’s preferences must be taken into account when deciding on an appropriate treatment plan. Patients with desmoid tumors are optimally managed in a multidisciplinary setting with close collaboration between surgeon, pathologist, diagnostic radiologist, radiation oncologist, and medical oncologist. When possible, surgical resection with negative margins is the preferred modality. When surgical resection with negative margins may prove disabling, surgery can be followed by postoperative radiation, although the role and efficacy of this are controversial. In locations where surgical extirpation is difficult or unfeasible, primary radiation, hormonal therapy, or chemotherapy should be considered. Familiar adenosis polyposis (FAP)-associated mesenteric lesions, sporadic tumors present without change for months or years, or tumors present in areas where progression will not present significant additional morbidity are candidates for observation only.     

Testicular tumors

Germ cell tumors of the testes represent a unique paradigm of diseases which can be cured even in extremely advanced phase. Unfortunately, this makes them unique among adult solid tumors. Seminoma and non seminoma are relatively rare with approximatively 25,000 patients in Europe per year, but numbers are increasing world wide. Different strategies are needed depending on stage and prognostic scores. Seminoma is extremely sensitive to radiation therapy and chemotherapy, while all germ cell tumors show a very good response to chemotherapy. Clinical stage I seminoma is currently treated with radiation, single course carboplatin or surveillance policy. Clinical stage I non seminoma can also be approached with different strategies such as retroperitoneal lymph node dissection, observation or one-two courses of standard chemotherapy. Stage II seminoma may be treated with either radiation or chemotherapy, while for all advanced stages chemotherapy is mandatory. Since the mid-eighties PEB (Cisplatin, Etoposide and Bleomycin) is the regimen of choice and no other schedule has proved superior in terms of efficacy. Surgery on the residual disease is crucial to the whole strategy and should be performed or attempted in all cases. Consequently, the correct treatment strategy for these tumors does not depend only on the ability of a single physician, but on a skilled team specialized in this particular tumor. Second line therapies (VeIP, PEI, TIP) can cure 25%–40% of patients, but improved strategies for resistant tumors are desperately needed. High-dose chemotherapy has shown very good results in some studies while being less impressive in others. In any case, it should remain an option for relapsing patients and could be used in some cases of upfront chemotherapy in patients with slow marker decline, but this should only be considered in referring centers.     

Hematologic tumors

Development of cytarabine and daunorubicin has made a cure for acute myeloid leukemia (AML) possible. Current first line chemotherapy is a combination of idarubicin plus cytarabine. Acute promyelocytic leukemia has the highest cure rate among AML due to the introduction of ATRA. Current first line chemotherapy for advanced Hodgkin's lymphoma is ABVD, based upon results of a prospective randomized study comparing MOPP, ABVD and MOPP/ABVD. CHOP has been frequently selected as first line chemotherapy for advanced non-Hodgkin's lymphoma, based upon results obtained in a phase III study that compared CHOP versus second and third generation combinations.     

Parathyroid tumors

Opinion statement Parathyroid tumors causing primary hyperparathyroidism are common and often remain undiagnosed, despite that the diagnostic work-up is uncomplicated in most patients. The patients often do not receive the appropriate curative treatment, which is surgical. Recent studies show that surgery is beneficial in patients with mild asymptomatic disease, especially in the reversal of bone disease, neuropsychologic symptoms, and dyslipoproteinemia. All patients with the disease deserve a referral to an endocrine surgeon for discussions regarding surgical intervention. Minimally invasive techniques performed in the ambulatory setting have evolved rapidly and show an extraordinary high success rate, low-morbidity rate, and are likely to become the standard treatment for most patients with primary hyperparathyroidism.     

Neuroendocrine tumors

Neuroendocrine tumors comprise a broad family of tumors, the most common of which are carcinoid and pancreatic neuroendocrine tumors. The NCCN Neuroendocrine Tumors Guidelines discuss the diagnosis and management of both sporadic and hereditary neuroendocrine tumors. Most of the recommendations pertain to well-differentiated, low- to intermediate-grade tumors. This updated version of the NCCN Guidelines includes a new section on pathology for diagnosis and reporting and revised recommendations for the surgical management of neuroendocrine tumors of the pancreas.