Patterns and Signal Intensity Characteristics of Pelvic Recurrence of Rectal Cancer at MR Imaging

Abstract

Magnetic resonance (MR) imaging is becoming the cross-sectional imaging modality of choice for follow-up of patients with previous rectal cancer to diagnose pelvic recurrence and plan for surgery. The authors conducted a retrospective review of MR imaging examinations performed at their institution for evaluation of local recurrence of rectal cancer in 42 patients. Twenty-six patients had undergone rectal anastomosis and 16 had undergone abdominoperineal resection. The mean interval between initial surgery and recurrence was 2.5 years. Recurrence sites were axial (involving the anastomosis) (n = 19); lateral (sidewall) (n = 6); anterior (prostate or seminal vesicle [n = 2], bladder [n = 4], ureter [n = 3], vagina or uterus [n = 5]); or posterior (presacral fascia [n = 11], sacrum [n = 2]). Other recurrence sites included the pelvic floor (n = 7), sciatic nerve (n = 2), obturator nerve (n = 1), perineum (n = 1), abdominal wall (n = 1), or adnexa (n = 1). Recurrence was confirmed at surgery or by evidence of tumor growth at follow-up imaging. Recurrence patterns, signal intensity characteristics, findings of unresectability, potential MR imaging pitfalls, and the role of MR imaging versus other modalities in evaluating recurrent rectal carcinoma are discussed. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg335115170/-/DC1.

Role of MRI in Postoperative Assessment and Detection of Recurrence in Cancer Rectum

“…In our study, the specificity , sensitivity and accuracy were about 85.7% , 92,3% , 94.9 % respectively which showed no significant changes from results of Lambregets et al (12) since specificity was 91 % , sensitivity was 100 % and accuracy was 95 % and Sinaei et al (13) (Sensitivity 90% and specificity was 100% ,accuracy was 96 %). Colosio et al (5) (Accuracy up to 99 % , sensitivity up to 100 % and specificity up to 86 %) Grosu et al (14) (Sensitivity 93% and specificity was 91%, accuracy 92 %).…”

Recurrent rectal cancer causing lumbosacral plexopathy with perineural spread to the spinal nerves and the sciatic nerve: An anatomic explanation

“…Once the tumor reaches the sacral plexus, it can continue to spread within neural structures in a proximal as well as a distal and cause various symptoms in relation to the affected structures, namely, the clinical entity known as neoplastic lumbosacral plexopathy (LSP) (see below). Proximally, it can involve sacral spinal nerves (Boyle et al, 2005;Sinaei et al, 2013) and extend to the lumbar plexus and lumbar spinal nerves (Sinaei et al, 2013) via the lumbosacral trunk (Gierada and Erickson, 1993) as in our cases ( Figs. 1 and 3).…”

“…3 and 5). Several other cases of the sciatic nerve (Rao et al, 1982;Gaeta et al, 1988;Kameyama et al, 1993;Beets-Tan et al, 2000;Sinaei et al, 2013) as well as obturator (Gaeta et al, 1988;Tan et al, 2011;Sinaei et al, 2013), pudendal (Gaeta et al, 1988), inferior gluteal, and posterior femoral cutaneous nerve involvement (LaBan et al, 1982) have been reported, which we believe, can also be explained anatomically: either as spread from the infiltrated lumbosacral plexus, as in our cases, or by direct tumorous invasion during their intrapelvic course with subsequent perineural spread.…”

“…Of these 136,830 deaths, rectal cancer makes up about 28% or 40,000 cases of the total incidence of colorectal cancer (Siegel et al, 2014) with recurrence estimated to be around 10% (Heriot et al, 2008). Several studies have reported cases of rectal cancer with neoplastic involvement of the lumbosacral plexus (Jaeckle et al, 1985;Thomas et al, 1985;Gierada and Erickson, 1993;Taylor et al, 1997;Jaeckle, 2010) and sciatic (Gaeta et al, 1988;Kameyama et al, 1993;Albright et al, 2000;Sinaei et al, 2013), obturator (Gaeta et al, 1988;Beets-Tan et al, 2000;Tan et al, 2011;Sinaei et al, 2013), pudendal (Gaeta et al, 1988), inferior gluteal (LaBan et al, 1982), and spinal nerves (Gierada and Erickson, 1993;Boyle et al, 2005;Dieguez, 2013;Sinaei et al, 2013). We hypothesized that these cases could be explained anatomically by perineural spread from the rectum to the lumbosacral plexus with further extension proximally to the spinal nerves or distally to the arborizing nerves.…”

Clinical Etiology of Hypermetabolic Pelvic Lesions in Postoperative Positron Emission Tomography/Computed Tomography for Patients With Rectal and Sigmoid Cancer

“…We opted to use visual inspection rather than an absolute standardized uptake value to define a hypermetabolic focus. Pelvic recurrence was classified according to the location of the lesion [ 4 ].…”