Colorectal and abdominal oncology surgery covers the operations Dr. Jabbar performs for cancers of the colon, rectum, anus, and appendix, plus several related conditions that frequently end up in the same operating room: peritoneal carcinomatosis, diverticulitis, and bowel obstruction.
The diseases on this page range from early cancers caught on a screening colonoscopy to acute surgical emergencies. The operations range from short outpatient anorectal procedures to multi-hour resections with pelvic reconstruction. This page describes the conditions and the operations Dr. Jabbar performs to address them, written for patients and families who want to understand what their diagnosis means and what surgery actually involves.
The conditions below are the most common reasons patients are referred to Dr. Jabbar’s practice for colorectal and abdominal oncology surgery. Each is covered briefly, focusing on the patterns that come up most often in the clinic.
Colon cancer is the most common cancer of the large intestine. It almost always starts as a benign polyp on the inner lining of the colon, which can become cancerous over the years if it is not removed. That long lead time is the reason screening colonoscopy works so well: most polyps caught early can be removed during the colonoscopy itself, before they ever become cancerous.
Early colon cancer often produces no symptoms. When symptoms appear, they can include a change in bowel habits (persistent diarrhea, constipation, or narrowing of the stool), rectal bleeding or blood mixed in the stool, ongoing abdominal cramping or discomfort, the feeling that the bowel does not fully empty, fatigue or weakness from slow blood loss, and unintended weight loss.
Risk rises significantly after age 45, which is why screening colonoscopy is now recommended starting at that age for average-risk patients. Other risk factors include a personal or family history of colorectal cancer or polyps, inherited syndromes (Lynch syndrome, familial adenomatous polyposis), inflammatory bowel disease, a low-fiber diet, a sedentary lifestyle, obesity, smoking, heavy alcohol use, and Black or African-American ancestry.
Diagnosis is made by colonoscopy with biopsy. Staging adds CT of the chest, abdomen, and pelvis to look for spread, plus a baseline CEA tumor marker drawn from blood.
Surgery is the primary treatment for colon cancer that has not spread. The operation removes the segment of colon containing the tumor along with the surrounding lymph nodes, and the remaining bowel is reconnected. Stage I disease is generally treated successfully by surgery alone. For most medically fit patients, Stage III disease is treated with surgery and chemotherapy. Stage IV treatment is individualized and may include systemic therapy, surgery, ablation, or other local treatments when appropriate.
Rectal cancer is a malignancy of the rectum, the last several inches of the large bowel just above the anal canal. Like colon cancer, it usually starts as an adenomatous polyp on the rectal lining. The biology overlaps with colon cancer, but the treatment is meaningfully different because of where the rectum sits: low in the pelvis, surrounded by the bladder, the prostate or vagina, the sphincter complex, and important pelvic nerves.
Symptoms include rectal bleeding (often bright red), changes in bowel habits, narrowing of the stool, tenesmus (a persistent urge to move the bowels without relief), rectal pain, the sensation that the bowel does not empty, and unintended weight loss. Risk factors overlap with those for colon cancer.
Workup combines a digital rectal exam, colonoscopy with biopsy, and rectal-specific staging using pelvic MRI, with endorectal ultrasound used selectively to define how deeply the tumor has invaded and whether nearby lymph nodes are involved. CT of the chest, abdomen, and pelvis is used to detect distant spread.
The treatment approach depends on stage and location. Early Stage I tumors can sometimes be treated with surgery alone. Locally advanced rectal cancer is commonly treated with total neoadjuvant therapy, using chemotherapy with selective or routine radiation depending on risk and the treatment plan, followed by total mesorectal excision when surgery is indicated. Carefully selected patients with a complete clinical response may be offered structured nonoperative surveillance, and some dMMR/MSI-H tumors may respond to immunotherapy. For tumors in the upper or middle rectum, that resection is a low anterior resection (LAR). For very low tumors where the sphincter cannot be preserved, the operation is an abdominoperineal resection (APR). Chemotherapy often continues after surgery.
Anal cancer is uncommon. It develops in the short canal at the very end of the digestive tract through which stool exits the body. Most anal cancers are squamous cell carcinomas — a different cell type from the adenocarcinomas that make up most colorectal cancers.
Symptoms include rectal bleeding, anal pain or pressure, a lump or mass felt at or near the anus, anal itching, changes in bowel habits, and discharge from the anus.
The most important risk factor is infection with human papillomavirus (HPV), which is implicated in more than 90 percent of cases. Other risk factors include multiple sexual partners, receptive anal intercourse, immunosuppression (HIV, organ transplant), smoking, older age, and a prior history of cervical, vulvar, or vaginal cancer.
Diagnosis is made with a digital rectal exam, anoscopy, and biopsy. Staging includes pelvic MRI and chest, abdominal, and pelvic CT; PET/CT is often added. The inguinal lymph nodes are specifically examined, because anal cancer drains to that lymph node region.
Treatment differs sharply from colon and rectal cancer. The first-line treatment for most anal cancers is not surgery — it is concurrent chemotherapy and radiation, an approach called the Nigro protocol, which successfully treats the majority of anal cancers without an operation. Surgery is reserved as salvage treatment when the cancer persists or recurs after chemoradiation. The salvage operation is an abdominoperineal resection (APR), which leaves a permanent colostomy. Very small, early, low-risk lesions can sometimes be treated with local excision.
Appendiceal cancer is rare. The appendix is a small tube hanging off the cecum (the first part of the colon), and the cancers that arise there include low-grade and high-grade mucinous neoplasms, adenocarcinoma, goblet cell adenocarcinoma, and neuroendocrine tumors. Most appendiceal cancers are discovered incidentally, on the pathology report after an appendectomy done for what was thought to be ordinary appendicitis.
When a mucinous appendiceal tumor ruptures — sometimes before any symptoms have brought it to attention — the mucin-producing cells can spread throughout the abdominal cavity and produce a slowly accumulating jelly-like material. This condition is called pseudomyxoma peritonei, or PMP; it is sometimes described as a “belly full of jelly.”
Symptoms are uncommon at first. Some patients present with right lower quadrant pain that looks exactly like appendicitis. PMP presents later, with gradually increasing abdominal distention, new bloating, a new hernia (increased abdominal pressure pushing out weak points in the abdominal wall), or pelvic pressure.
Diagnosis is most often made on pathology after appendectomy. When PMP is suspected, CT and MRI reveal characteristic mucinous deposits that “scallop” the liver and spleen. Tumor markers (CEA, CA 19-9, CA 125) help with monitoring.
Treatment depends on the subtype and the extent of spread. Additional surgery after appendectomy depends on the appendiceal tumor’s histology, grade, margins, nodal risk, and spread; a single 2-centimeter cutoff does not apply to every appendiceal cancer subtype. For mucinous spread with PMP, the curative-intent standard of care is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC), performed at specialized peritoneal-surface malignancy centers.
Dr. Jabbar does not perform HIPEC. He evaluates patients with appendiceal cancer and PMP, performs the right hemicolectomy or other surgical components within his scope, and coordinates referral to a HIPEC center when patients are candidates.
Peritoneal carcinomatosis is the medical term for cancer that has spread to the peritoneum, the thin tissue that lines the inside of the abdominal cavity and covers the abdominal organs. It is a regional pattern of metastasis; the primary cancer is usually colorectal, appendiceal, ovarian, gastric, or peritoneal mesothelioma.
Symptoms include progressive abdominal distention (often from ascites, fluid accumulating in the abdomen), vague abdominal pain or pressure, early fullness with meals, nausea, decreased appetite, weight loss, and bowel obstruction symptoms when peritoneal deposits begin to compress or kink the bowel. Many cases are discovered on imaging done for an unrelated reason.
Workup includes CT and MRI of the abdomen, which can show peritoneal nodularity, “omental caking,” or ascites. Cytology of ascites fluid can confirm the presence of malignant cells, and tumor markers are followed. Diagnostic laparoscopy is often used to confirm the diagnosis, assign a Peritoneal Cancer Index (PCI) score to quantify the extent of disease, and determine whether a patient is a candidate for curative-intent surgery.
Treatment depends heavily on the primary cancer and the extent of peritoneal spread. Systemic chemotherapy is the backbone for most patients. At specialized centers, selected patients may benefit from complete cytoreductive surgery. Whether HIPEC is added depends on the primary cancer, disease burden, regimen, and multidisciplinary review; benefit is not established equally across tumor types.
Dr. Jabbar does not perform HIPEC. He evaluates patients with peritoneal disease, performs the surgical components within his scope (debulking, obstruction relief, palliative resections, ostomies), and coordinates referral to a HIPEC center when patients are candidates.
These two conditions are grouped together because both are common acute or chronic surgical decision points for the colon.
Diverticulitis is inflammation or infection of small outpouchings (diverticula) that form in the colon wall, most often in the sigmoid colon. The classic presentation is steady, often severe pain in the left lower quadrant, along with fever, nausea, and a change in bowel habits. Risk factors include age over 40, a low-fiber diet, obesity, smoking, a sedentary lifestyle, and certain medications (NSAIDs, steroids, opioids).
CT of the abdomen and pelvis is the diagnostic test of choice. Most uncomplicated cases are treated with bowel rest and, in selected cases, antibiotics, on an outpatient basis. Urgent surgery may be needed for complications such as generalized peritonitis, uncontrolled sepsis, or obstruction. Elective surgery is individualized based on complications, symptom burden, quality of life, immune status, and operative risk rather than the number of prior episodes alone.
The most common operation is sigmoid colectomy. In the elective setting, it is done laparoscopically or robotically with primary anastomosis. In the emergent setting, the decision is between sigmoid resection with primary anastomosis (sometimes with a temporary diverting ileostomy) and a Hartmann’s procedure (resection plus end colostomy), reserved for patients who are unstable or have severe contamination.
Intestinal obstruction is a blockage that prevents the normal passage of food, fluid, gas, and stool through the small or large intestine. The most common causes in adults are post-surgical adhesions, hernias, tumors (often colon cancer), volvulus (twisting of the bowel), strictures, and inflammatory bowel disease. Patients present with crampy waves of abdominal pain, abdominal distention, vomiting, the inability to pass gas or stool, and loss of appetite.
Diagnosis combines a physical exam, plain abdominal X-rays, and a CT scan to identify the cause and rule out complications such as bowel ischemia (loss of blood supply) or perforation. Initial management includes nothing by mouth, IV fluids, electrolyte correction, and nasogastric tube decompression. Many partial small-bowel obstructions from adhesions resolve without surgery. Urgent surgery is required for signs of ischemia, strangulation, perforation, closed-loop obstruction, incarcerated hernia, or clinical deterioration. Management of a complete obstruction otherwise depends on its cause and may include surgery, endoscopic treatment, or carefully monitored nonoperative care.
The operations below are the most common procedures Dr. Jabbar performs for the conditions described above. Whenever the disease and anatomy allow, they are performed robotically through small incisions. When the case requires it, the same operations are performed open.
A colectomy removes a portion of the colon along with its blood supply and the regional lymph nodes that drain it. The two remaining ends of the bowel are then reconnected — a step surgeons call an anastomosis. The specific version of colectomy depends on where in the colon the disease sits:
Dr. Jabbar performs colectomy through small abdominal incisions using the robotic platform whenever the disease and anatomy allow. Open surgery is reserved for very large tumors, hostile scarred anatomy from prior operations, or emergencies.
Hospital stay for a minimally invasive colectomy is typically two to four days. Many patients are managed on an enhanced recovery (ERAS) protocol that focuses on early walking, early eating, and minimizing narcotic pain medication.
A low anterior resection (LAR) is the operation for cancers of the upper and middle rectum. It removes the cancer-bearing segment of the rectum along with the surrounding mesorectum (the fatty tissue containing the lymph nodes that drain the rectum), using a technique called total mesorectal excision, or TME. The remaining colon is then sewn or stapled to the lower rectum, preserving the anal sphincter and continence. A temporary diverting loop ileostomy is often created to protect the new pelvic connection while it heals, and is reversed in a second operation a few months later.
LAR is the standard operation for rectal cancers that sit high enough in the rectum to allow an adequate margin without removing the sphincter. It is usually performed after neoadjuvant chemoradiation or total neoadjuvant therapy for locally advanced disease.
The pelvis is a narrow space, and the dissection has to stay close to the rectum without injuring the pelvic nerves that control bladder and sexual function. The robotic platform is well suited to this work — particularly in the narrow male pelvis — because the magnified three-dimensional view and wristed instruments allow precise dissection in tight quarters.
Hospital stay is typically four to seven days for minimally invasive LAR. Recovery includes management of the temporary ileostomy until it is reversed.
An abdominoperineal resection (APR) is the operation for very low rectal cancers, and for anal cancers that have not responded to chemoradiation, when the tumor sits so close to the sphincter complex that the anus cannot be preserved with a clean margin. APR removes the lower rectum, the anal canal, the surrounding sphincter muscles, and a portion of the sigmoid colon, with both an abdominal phase and a perineal phase. Because the anus is removed, the patient is left with a permanent end colostomy on the abdominal wall.
Proctectomy refers more broadly to removal of the rectum, with or without sphincter preservation, for cancer or for severe benign conditions such as ulcerative colitis (typically as part of a total proctocolectomy with ileal pouch reconstruction), refractory Crohn’s proctitis, or intractable radiation proctitis.
APR is technically demanding because of the depth of the pelvic dissection and the proximity to the presacral venous plexus, the ureters, the pelvic nerves, the bladder, and the prostate or vagina, along with the perineal wound itself. Dr. Jabbar performs APR robotically whenever the anatomy allows, with the abdominal phase done through small incisions and the perineal phase done from below.
Hospital stay is typically five to eight days. Over the past two decades, the APR rate has declined significantly as neoadjuvant therapy and sphincter-preserving techniques have improved.
These are short outpatient procedures for the common benign anorectal conditions that bring patients to a colorectal practice. Most are done with same-day discharge.
An anal fissure is a small tear in the lining of the anus, usually caused by passing a hard or large stool. Most fissures heal with conservative measures (fiber, fluids, stool softeners, sitz baths) and topical agents that relax the sphincter (nitroglycerin or nifedipine). Persistent fissures can be treated with Botox injection into the internal sphincter. Chronic fissures that do not heal with medical therapy are treated with lateral internal sphincterotomy, a brief operation that divides a small portion of the internal sphincter to break the spasm and allow healing.
A perianal abscess is a collection of pus in the tissues around the anus, almost always originating from an infected anal gland. Treatment is prompt incision and drainage. Most abscesses are drained in the office or emergency department under local anesthesia; deeper or complex abscesses are drained in the operating room. Antibiotics alone are rarely sufficient — drainage is typically required.
An anal fistula is an abnormal tunnel between the anal canal and the perianal skin. Most fistulas develop after an anorectal abscess, when the original tract does not fully close. Symptoms include persistent drainage, recurrent abscesses, perianal pain, and skin irritation. Diagnosis is made on exam, sometimes with MRI or endoanal ultrasound to map the tract relative to the sphincter.
The chosen operation depends on the fistula’s position relative to the sphincter muscles, because preserving continence is the priority. Options include fistulotomy for simple low fistulas; seton placement for complex or high fistulas (a drain that matures the tract while preserving the sphincter); and sphincter-preserving operations such as LIFT (ligation of the intersphincteric fistula tract), endorectal advancement flap, and fistula plug. Fistulas associated with Crohn’s disease are handled differently and may require long-term treatment with biologic medication alongside surgery.
