Ron G. Landmann

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Although small cell carcinoma of the gastrointestinal (GI) tract is well-recognized, nonsmall cell type high-grade neuroendocrine carcinoma (HGNEC) of this site remains undefined. At the current time, neither the World Health Organization nor American Joint Committee on Cancer includes this condition in the histologic classifications, and consequently it is(More)
Folate receptor alpha (FRalpha) has emerged as a potential cancer therapy target with several folate-linked therapeutic agents currently undergoing clinical trials. In addition, FRalpha expression in tumors may offer prognostic significance. Most studies on FRalpha expression used reverse transcriptase polymerase chain reaction or cytofluorimetric assays.(More)
PURPOSE Adjuvant therapy for Stage II colon cancer remains controversial but may be considered for patients with high-risk features. The purpose of this study was to assess the prognostic significance of commonly reported clinicopathologic features of Stage II colon cancer to identify high-risk patients. METHODS We analyzed a prospectively maintained(More)
INTRODUCTION/HYPOTHESIS Over-expression of the c-Met receptor tyrosine kinase has been described in a variety of cancers and implicated in tumor progression. Unlike some solid tumors, current evidence indicates that c-Met activation in colon cancer is unrelated to gene mutation, is ligand dependent, and occurs via a paracrine fashion. We hypothesize that(More)
Locally advanced and locally recurrent colon cancers pose a surgical challenge with tumors extending into surrounding structures and organs. Anticipation of the need for an extended surgical resection, often with multivisceral en bloc organ removal, is critical for surgical planning. For both primary and recurrent tumors, postsurgical long-term survival is(More)
BACKGROUND Chronic tubo-ovarian abscess is an uncommon finding in postmenopausal women. This abscess may rupture or fistulize to adjacent organs into the ischiorectal space. CASE A gravida three, para three, postmenopausal woman with extensive sigmoid diverticulosis presented with perianal fistula of 2 years' duration. Magnetic resonance imaging showed(More)
PURPOSE This study examines surgical salvage of locally recurrent rectal cancer following transanal excision of early tumors. METHODS Through retrospective review of a colorectal database we identified 50 patients who underwent attempted surgical salvage for local recurrence following initial transanal excision of T1 or T2 rectal cancer. Eight patients(More)
PURPOSE Estimates of recurrence after curative colon cancer surgery are integral to patient care, forming the basis of cancer staging and treatment planning. The categoric staging system of the American Joint Committee on Cancer (AJCC) is commonly used to convey risk by grouping patients based on anatomic elements. Although easy to implement, there remains(More)
Successful selection of patients with rectal cancer for local excision requires accurate preoperative lymph node staging. Although endorectal ultrasound is capable of detecting locally advanced disease, its ability to correctly identify nodal metastases in early rectal lesions is less well described. This study examines the accuracy of endorectal ultrasound(More)
Paradoxical puborectalis contraction and increased perineal descent are two forms of functional constipation presenting as challenging diagnostic and treatment dilemmas to the clinician. In the evaluation of these disorders, the clinician should take special care to exclude anatomic disorders leading to constipation. Physical examination is supplemented by(More)