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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_917_Библиотеки_им_академика_М_И_Перельмана.pdf
Unexpected Findings During
Laparoscopic Colectomy forCancer:
25
Techniques andStrategies
EricG.Weiss andGiovannada Silva
Introduction
Laparoscopic colectomy for colon cancer is widely accepted and perhaps the procedure of choice for the majority of patients with colon cancer. Despite sophisticated
preoperative imaging that typically includes a CT scan of the chest, abdomen, and
pelvis, as recommended by the National Comprehensive Cancer Network (NCCN)
Guidelines and most surgeons’ practices, unexpected intraoperative ndings are
sometimes encountered. This chapter focuses on eight ndings that may be encountered during the performance of laparoscopic surgery for colon cancer and how to
manage these unexpected ndings so that patient outcome is optimized.
Identification ofthePrimary Tumor or Lack Thereof
Of primary importance in laparoscopic surgery for colon cancer are identication of
the cancerous segment and its removal in an oncologically appropriate manner.
Although this seems basic and routine, in the early learning curve of laparoscopic
colon cancer management, wrong segments were removed for a variety of reasons.
Surgeons often embarked on laparoscopic surgery to remove segments based solely
on colonoscopic reports rather than intraoperative conrmation. This leads to the
realization that preoperative marking using tattoo techniques was extremely important owing to the fact that, with the loss of tactile sensation associated with
E. G. Weiss (*) · G. da Silva
Department of Colorectal Surgery, Cleveland Clinic Florida, Weston, FL, USA
e-mail: weisse@ccf.org; dasilvag@ccf.org
© Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) 2020
P. Sylla et al. (eds.), The SAGES Manual of Colorectal Surgery,
https://doi.org/10.1007/978-3-030-24812-3_25
399
400
E. G. Weiss and G. da Silva
laparoscopic surgery, the surgeon is more highly reliant on other methods of identifying tumors intraoperatively or preoperatively. Thus the importance of reviewing
the preoperative imaging, even when a report does not explicitly state that there is a
mass or tumor identied in a segment, cannot be overstated. Subtle ndings, particularly with the surgeon’s familiarity with the colonoscopy report, their own physical examination, and, possibly, their own endoscopy (colonoscopy or exible
sigmoidoscopy) depending on the situation, will often allow for conrmation of a
tumor location. If a PET/CT has been ordered, unless the tumor is mucinous, the
location of the tumor is typically PET-avid and will reappear, thus adding a corroborating study in addition to the colonoscopy. In cases of rectal or rectosigmoid
tumors, exible endoscopy is notoriously inaccurate in identifying the specic level
of the tumor in relation to the anal verge or dentate line. Thus, in these cases, it
behooves all surgeons to perform preoperative rigid proctoscopy or exible sigmoidoscopy in the ofce or endoscopy suite to ensure that the tumor is a colonic
rather than a rectal lesion. This is important both to ensure removal of the appropriate bowel segment and, in the case of rectal cancer, to consider alternative therapeutic options based on local staging such as neoadjuvant chemoradiotherapy, a
diverting stoma, chemotherapy, etc. Other scenarios in which preoperative imaging
can be useful is obtaining a water-soluble contrast enema study (WSCE) in the case
of incomplete colonoscopy due to obstruction or partial obstruction. This will provide information regarding the areas not visualized by colonoscopy as well as a
“hard copy, road map” as to the location of the tumor.
At the time of the initial colonoscopy, the endoscopist should consider marking
a tumor with tattoos [1]. Although until recently there was no standard method of
tattooing for localization of tumors during laparoscopic colectomy, several principles should be adhered to. Tattooing should always be placed distal to the tumor so
that removal of the tattoo within the segment ensures removal of the tumor. Tattooing
should be placed in multiple quadrants of the bowel wall to facilitate visualization
of the tattooing. If only one or two tattoos are placed and they happen to be in the
mesenteric surface, they will at times be difcult if not impossible to visualize.
Therefore placing tattoos in three or four quadrants should be routinely performed.
Reviewing the colonoscopy report is sometimes helpful, but the specics of marking are often omitted, and the reports only conrm that marking/tattooing was performed. In these cases, discussion with the endoscopist can be useful. Furthermore,
in cases where an endoscopist frequently refers patients, it is helpful to discuss the
specics of marking/tattooing in advance, which will often preclude the need for
repeat colonoscopy and further marking/tattooing or intraoperative maneuvers to
identify the correct segment with its associated tumor (Fig.25.1).
At the onset of a laparoscopic procedure, an initial diagnostic laparoscopy
should be performed. This entails a general inspection of the peritoneal cavity,
liver, and pelvis to look for identifying characteristics of an underlying colonic
tumor such as an obvious mass, adherence of omentum to the colon, puckering of
the serosa, serosal involvement by the tumor, and visualization of the tattoo markings. If none of the characteristics of a colonic tumor are present and tattooing is
25 Unexpected Findings During Laparoscopic Colectomy forCancer: Techniques…
Fig. 25.1 Preoperative
tattooing
401
not visualized, one needs to consider why the tattoos are not visualized. Is the
surgeon looking in the wrong location? Just because a colonoscopy report states a
tumor is in the sigmoid, it does not mean that it could not be in the descending,
splenic exure, transverse colon, and at times even more proximal. Flipping the
omentum up over the transverse colon should be undertaken as sometimes this
maneuver will allow visualization of the tattoos/markings. Lastly, mobilizing the
exure(s) will sometimes allow visualization if tattoos are on the mesenteric surface or blocked by folded or adhesed areas. Another approach is to place a hand
port through the expected extraction site to restore tactile sensation and help to
identify the tumor and its associated segment.
If all of the above maneuvers are unsuccessful, intraoperative colonoscopy
should be performed. For most laparoscopic colorectal procedures, patients should
be initially positioned in lithotomy, allowing access to the anus for such potential
needs as intraoperative colonoscopy. If this has not already been done, repositioning
will be required. Ideally, intraoperative colonoscopy should be performed using
CO
endoscopy equipment [2]. If unavailable, clamping the terminal ileum will
2
prevent insufation of the small bowel with room air, which will limit working
space and make completion of the surgery more difcult. Once the tumor is identied, placing a tattoo intraoperatively, placing a suture at the site of the tumor, and
marking with endoclips are all viable options to preserve identication of the tumor
once the colonoscopy has been completed. With all of the tools available both
402
preoperatively and intraoperatively, a “blind colectomy”– without the ability to
identify the correct segment prior to excision– should never be performed.
E. G. Weiss and G. da Silva
Invasion ofOther Organs
Despite preoperative, routine, and high-quality CT scans of the chest, abdomen, and
pelvis, more advanced disease does sometimes present intraoperatively. Thus on
initial diagnostic laparoscopy, assessment for adherence to or involvement of the
tumor to other structures should be undertaken. Structures that a primary colon
cancer may be adherent to or invading into would include the abdominal wall,
omentum, small bowel, duodenum, stomach, retroperitoneum, bladder, and female
reproductive organs including the fallopian tubes, ovaries, uterus, and/or vagina.
Other structures may be less frequently involved. Regardless, intraoperative assessment as to the resectability of these structures en bloc with the primary tumor needs
to be undertaken. In addition, a decision needs to be made as to whether the procedure should be continued as a laparoscopic approach or converted to an open procedure [3]. Involvement of other specialists, if available, may also be required
depending on the expertise of the operating surgeon and the organ(s) involved.
One of “the out of the OR” considerations is the potential lack of informed consent for the additional surgery that may be necessary. Speaking to family members
may be of some benet; however, from a medicolegal standpoint, unless a family
member has healthcare power of attorney on behalf of the patient, consent may not
be binding or legal. Regardless, doing what is in the patient’s best interest should
take precedence and should guide decisions.
The best decision may sometimes be to abort the procedure. However, this is
advisable only if an initial diagnostic laparoscopy has been performed. If the procedure has advanced (mobilization, vascular division, etc.) in an effort to recognize
any secondary involvement of structures, aborting the procedure is not an option.
If the decision is made to proceed with en bloc resection, the operative team
should take a “time-out” to discuss the new operation and the steps required and the
need for other teams or services, if required. This will then allow the OR staff, the
operative team(s), and potential additional services to be called and prepared.
Synchronous Masses/Tumors
Synchronous tumors or cancers are relatively rare, occurring in less than 1–2% of
patients with colon cancer, and are usually intraoperatively identied rather than
preoperatively during colonoscopy. Although there is a small “miss rate” on colonoscopy, more typically a synchronous tumor would be proximal to a partially or
obstructing tumor that was not traversed at the time of colonoscopy, thereby leaving
a segment(s) of the colon that was not endoscopically evaluated. In cases where a
complete colonoscopy cannot be performed, a preoperative WSCE is recommended.
Not only does WSCE conrm the location of the primary tumor, it can also assess
25 Unexpected Findings During Laparoscopic Colectomy forCancer: Techniques…
areas that were not endoscopically evaluated. In cases where a second tumor is
noted preoperatively, an extended resection or, less commonly, two segmental
resections should be performed [4, 5].
If the synchronous tumor is noted intraoperatively, similar options are available
to the surgeon and patient. Synchronous tumors should raise the suspicion of hereditary nonpolyposis colorectal cancer (HNPCC) in the appropriately aged patient.
Depending on the location of the rst and second tumors, the options remain as
above: extended resection such as an extended right colectomy, subtotal colectomy,
or total colectomy with ileorectal anastomosis. Even in cases of total abdominal
colectomy with ileorectal anastomosis, functional outcomes are good with an average of 24-hour bowel function of two to four bowel movements per day.
403
Meckel’s Diverticulum
Meckel’s diverticulum occurs in 2% of the population as per the “rule of 2s”: a location of 2feet from the ileocecal valve and ectopic gastric tissue within the diverticulum predisposing to GI bleeding in 2% of cases. Incidentally nding a Meckel’s
diverticulum is rarely an indication for surgical excision unless bleeding, perforation, diverticulitis, and obstructions have occurred prior to the incidental identication [6]. However, if a decision is made to excise a Meckel’s diverticulum, it is
generally safe and well tolerated.
Peritoneal Carcinomatosis
Patients with peritoneal carcinomatosis (PC) typically have other sites of metastasis. However, PC may be the only site in up to 25%, and in 10% it is diagnosed at
the time of surgery [7]. The presence of PC implies a poorer prognosis to the patient.
Traditionally, management of PC has included a combination of systemic therapy
and cytoreductive surgery (CRS) followed by intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC) with mitomycin-C or oxaliplatin (Fig. 25.2).
Recently, a French randomized phase III multicenter trial has questioned the addition of HIPEC in these patients showing no difference in survival and an increased
incidence of severe complications when compared to CRS alone [8]. Nevertheless,
several studies have shown that CRS/HIPEC confers increased median 5-year survival of approximately 30% after R0/R1 resection, depending on the extent of disease and the completeness of CRS [7, 9].
Up-front knowledge of the presence of PC allows the surgeon to prepare for
CRS, which entails removal of all visible disease, omentum/parietal peritoneum
followed by HIPEC, which is time-consuming and demands structure with special
equipment and drugs. More importantly, advance knowledge provides an opportunity for a thorough preoperative discussion with the patient regarding the prognosis,
benets, and morbidity related to the procedure. CT scan is still considered the best
imaging modality to detect PC.The presence of nodular or plaque-like soft tissue
404
Fig. 25.2 Peritoneal
carcinomatosis. (Courtesy
of Patricia Sylla, MD)
E. G. Weiss and G. da Silva
masses and thickening of the mesentery in association with ascites are suggestive of
the diagnosis. Unfortunately, CT scan accuracy is approximately 65% with low
sensitivity for implants less than 1cm. This results in often missed or underestimated PC on preoperative imaging [10].
When the surgeon encounters unexpected PC, the rst step is to evaluate the
extent of the disease. The peritoneal cancer index (PCI) is one of the most commonly
used tools to evaluate the extent of disease. The PCI scores the lesion size from 0 to
3 (0 no tumor, 1 implants ≤5mm, 2 >5–50mm, or 3 >50mm) in 13 abdominopelvic
regions, for a score range from 0 to 39 (13×3). Patients who are physically t and
have limited (PCI<20) and potentially completely resectable and/or ablatable disease with no extra-abdominal metastasis are candidates for the procedure [8]. In
these cases, a surgeon experienced with CRS/HIPEC should be called in for evaluation and/or the extent of the disease well documented with photos or video. While
colectomy has been performed in these scenarios, few studies have suggested worse
outcomes with CRS/HIPEC preceded by nondenitive surgical intervention due to
violation of the planes and adherence of cancer cells in traumatized tissue [11]. A
better option might be to perform biopsies and, at a later date, colectomy with concomitant CRS/HIPEC.Similarly, if the patient has multiple liver metastasis, CRS
should not be attempted. The implants should be biopsied and the primary tumor left
in place. If the patient is symptomatic, however, the tumor might be resected and/or
a stoma constructed or a gastrostomy tube placed, as indicated. In all situations, the
25 Unexpected Findings During Laparoscopic Colectomy forCancer: Techniques…
case should be discussed in a multidisciplinary team, and the patient is referred for
combination treatment with systemic chemotherapy, CRS, and HIPEC.
405
Liver Metastasis
Liver metastasis is present in approximately 25% of patients diagnosed with
colorectal cancer. CT scan is the imaging modality of choice for patients undergoing colectomy for colon cancer. As with PC, the diagnosis of liver metastasis alters
the patient’s treatment and prognosis. High-quality preoperative imaging is crucial
as it demonstrates the number, size, and distribution of the metastasis and the volume of the remaining liver, which is important to determine the resectability of the
lesions(s) and best treatment approach.
When the surgeon encounters lesions during laparoscopic exploration that are
suggestive of metastasis not detected preoperatively, the decision to proceed with
colectomy depends on the number/burden of the liver by the lesion(s) and the
patient’s symptoms. If the lesions are multiple and occupy a signicant portion of
the liver, biopsy of the most assessable lesion might be performed using an energy
device and sent for frozen biopsy, if available. If the patient is asymptomatic, the
surgeon may forego colectomy, whereas resection should be performed in the presence of symptoms such as obstruction or bleeding. If only few lesions are noted, the
surgeon may proceed with colectomy. In all cases, high-quality imaging +/− biopsy
should be obtained postoperatively for further treatment planning. In addition, the
patient should be referred to chemotherapy and hepatobiliary surgery, and the case
should be discussed in a multidisciplinary tumor board.
Ovarian Mass
The differential diagnosis for ovarian mass includes functional cyst, endometrioma,
and benign or malignant neoplasm. The incidence of malignant ovarian tumors
increases with age. Approximately 5–30% of ovarian tumors originate from other
sites and 3–8% are from the colon. Whereas the appearance of a benign cyst lled
with clear uid is reassuring, the ndings of a large, irregular, solid, multiloculated,
or xed mass are concerning. The approach to ovarian mass includes a diagnostic or
staging phase and an operative phase. The diagnostic phase entails washing for
cytologic examination and thorough inspection of all pelvic organs, peritoneal surfaces, the upper abdomen, the diaphragm, and the liver, in order to rule out macroscopic evidence of malignancy. Surgical treatment of known ovarian tumors may
include debulking with removal of all visible disease and a staging procedure with
hysterectomy, bilateral salpingo-oophorectomy, omentectomy, peritoneal biopsies,
and bilateral pelvic and para-aortic lymphadenectomy [12]. This might be followed
406
E. G. Weiss and G. da Silva
by intraperitoneal or systemic chemotherapy. Metastatic ovarian tumor may be
managed with unilateral or bilateral oophorectomy. Careful preoperative evaluation
should identify women who have suspicious adnexal masses, and the patient is
referred to a gynecologic oncologic surgeon for possible oophorectomy and immediate staging by laparoscopy or laparotomy at the time of colon resection.
If an incidental isolated ovarian mass is found during colectomy for colon cancer, the surgeon may proceed as planned with colectomy, and gynecologic oncology
consult should be obtained, if available. If the mass is suspicious and the patient is
postmenopausal, after consent is obtained from the next of kin, the specialist may
perform oophorectomy with care to avoid rupture and sent for frozen biopsy. If
malignancy is conrmed, immediate full staging including peritoneal washings,
total abdominal hysterectomy with bilateral salpingo-oophorectomy, omentectomy,
peritoneal biopsies, and pelvic and para-aortic lymphadenectomy might be performed, or in a second surgery [13]. This staging procedure can be performed by
laparotomy or laparoscopy in experienced hands. If frozen biopsy is not available or
the patient’s wishes are unknown, the ovary may be sent for permanent pathology
and a second surgery performed at a later date by a specialist after discussion with
the patient. Tumor markers can be sent intraoperatively or in the postoperative
period.
In a premenopausal patient, reproductive and hormonal issues render the scenario more complex. A gynecologic oncology surgeon is called in for evaluation
and/or the ndings documented and photos taken. Oophorectomy should be performed at a later date after proper discussion and counseling relative to the patient’s
reproductive wishes and expected hormonal changes. In cases when a benignlooking cyst is incidentally found, management should be postponed and the patient
referred to a specialist.
Malrotation
Intestinal malrotation is a rare congenital disorder that results from incomplete rotation and xation during fetal development. It is usually diagnosed in the rst month
of life and is extremely rare in adults. Presentation may be acute or chronic, with
symptoms of obstruction with abdominal pain and vomiting. Although preoperative
CT scan is usually obtained in patients undergoing colectomy for colon cancer, the
diagnosis of malrotation is often missed. Findings of reversed relation of superior
mesenteric artery and superior mesenteric vein with the vein to the right of the
artery, a duodenojejunal junction lying on the right without crossing over to the left
(corkscrew sign), a whirled appearance of the vasculature entering the volvulus
(whirlpool sign), small bowel loops in the right upper abdomen, lack of visualization of the cecum in the right lower abdomen, and dilatation of small bowel are
suggestive of malrotation (Fig.25.3a, b). The best imaging modality is upper gastrointestinal series, which may show the duodenojejunal exure to the right of the
25 Unexpected Findings During Laparoscopic Colectomy forCancer: Techniques…
407
Fig. 25.3 (a) CT scan
showing superior
mesenteric artery dorsal to
superior mesenteric vein.
(a Source: From Donaire
etal. [14]. Copyright ©
2013 Michael Donaire
etal. Used under the
Creative Commons
Attribution License 3.0,
which permits unrestricted
use, distribution, and
reproduction in any
medium, provided the
original work is properly
cited.). (b) Duodenum
does not cross the midline
a
b
abdomen. Upon entering the abdominal cavity, the surgeon may encounter the small
bowel to the right of the abdomen (Fig.25.4). Lysis of adhesions should be carried
on until the bowel is mobilized off the right abdomen. The colon might be difcult
to visualize as it may be dislodged to the left. One should not hesitate to convert to
open surgery to properly identify the anatomy. Care should be taken with division
of the blood supply.
408
Fig. 25.4 Intestinal
malrotation: cecum to the
left and sigmoid to the
right
E. G. Weiss and G. da Silva
Conclusion
Unexpected intraoperative ndings are minimized by thorough and high-quality
preoperative evaluation and imaging. The decision-making process is based on the
knowledge of how to proceed when these ndings are known prior to surgery; morbidity of additional treatment; natural history of the disease; surgeon’s experience,
resources, and skills; availability of the next of kin; the pathologist for frozen biopsy
in some cases; and, above all, the patient’s best interest.
References
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of current practice and outcomes for laparoscopic colonic resection following endoscopy at a
tertiary care centre. Can J Surg. 2017;60(6):394–8.
2. Nakajima K, Lee SW, Sonoda T, Milsom JW. Intraoperative carbon dioxide colonoscopy:
a safe insufation alternative for locating colonic lesions during laparoscopic surgery. Surg
Endosc. 2005;19(3):321–5.