SURGERY 2Case: Abdominal Mass

Sales. Salonga. San Diego. San Pedro. Sañez.

56 y/o male farmerCC: Abdominal Mass

5 months PTA Gradual abdominal enlargement Palpable abdominal mass Accompanied by a feeling of abdominal fullness

and early satiety Weight loss of around 10 lbs.

ROS: Unremarkable

Personal History: Smokes around 10-15 sticks of cigarettes a

day for the past 20 years He drinks 2-3 bottles of beer every day.

No previous hospitalization.

Physical Examination

BP 150/90; PR 78 bpm; RR 15 cpm; Temp 36.7; Weight: 130 lbs; Height: 5 ft 7 in (BMI = 20.4)

HEENT - pinkish palpebral conjunctivae; no palpable cervical lymph nodes

Heart and Lungs: essentially unremarkable Abdomen: palpable mass at the periumbilical area

with a smooth surface, non-tender, with ill-defined borders, measuring around 10 cm at its widest diameter. It is also not ballotable and does not move with respiration. Bowel sounds are normal.

Rectal exam: ⊖

Admission Work-ups

Blood tests Hemoglobin 130 Hematocrit 40 WBC 8000/cumm

PMN 70 lymphocytes 25 eosinophils 5

Total Protein 75 (60 to 83 g/L) Albumin 55 (35 to 55 g/L) Globulin 20 (23 to 35 g/L) PT: 13 sec, Control 12 sec APTT: 40 sec

Chest x-ray – normal

Clinical Impression

Retroperitoneal Mass, probably malignant

Retroperitoneal Mass

Clinical presentation Enlarging abdominal mass Pain, symptoms of compression Weight loss PE:

palpable mass ill-defined borders not movable smooth surface

Retroperitoneal Malignancies Malignancies in the retroperitoneum may result from the

following: Extracapsular growth of a primary neoplasm of a retroperitoneal

organ such as the kidney, adrenal, colon, or pancreas Development of a primary germ cell neoplasm from embryonic rest

cells Development of a primary malignancy of the retroperitoneal

lymphatic system, for example, lymphoma Metastases from a remote primary malignancy into a retroperitoneal

lymph node, for example, testicular cancer Development of a malignancy of the soft tissue of the

retroperitoneum, for example, sarcomas and desmoid tumors The most common primary malignancy of the

retroperitoneum is a sarcoma.

Sabiston Textbook of Surgery, 18th ed.

Retroperitoneal Sarcoma Most retroperitoneal tumors are malignant 1/3 are soft tissue sarcomas

Schwartz’s Principles of Surgery, 8th ed.

Retroperitoneal Sarcoma

Asymptomatic abdominal mass, often after the primary tumor has reached a considerable size

less common symptoms Gastrointestinal hemorrhage Early satiety nausea and vomiting weight loss lower extremity swelling lower extremity paresthesia and paresis

Sabiston Textbook of Surgery, 18th ed.

Radiologic Assessment

CT of the abdomen and pelvis Define the extent of the tumor Relationship to surrounding structures,

particularly vascular structures Imaging should also encompass:

liver for the presence of metastases abdomen for discontiguous disease kidneys bilaterally for function

Schwartz’s Principles of Surgery, 8th ed.

Radiologic Assessment

Thoracic CT is indicated to detect lung metastases

For patients presenting with an equivocal history, an unusual appearance of the mass, an unresectable tumor, or distant metastasis, CT-guided core-needle or laparoscopic biopsy is appropriate to obtain a sample for tissue diagnosis.

CT Scan of the Abdomen

On the 2nd hospital day, he undergoes a diagnostic procedure. Histopathology is shown

below:

Atypical lipomatous tumor of retroperitoneum which has combined lipoma-like, sclerosing and secondary

myxoid features, and which has undergone dedifferentiation

Shows border between 2 histopathological variants: LEFT, well-differentiated liposarcoma; RIGHT, dedifferentiated liposarcoma

LIPOSARCOMA

Role of Pre-operative Biopsy

PRE-OPERATIVE BIOPSY

Many histologic subtypes of sarcoma. Despite the variety of histologic subtypes,

sarcomas have many common clinical and pathologic features.

Histologic assessment is usually performed for definite diagnosis.

PRE-OPERATIVE BIOPSY

CT and MRI: initial imaging modalities for imaging liposarcoma and other soft tissue tumors Effective for diagnosis of invasion or

metastasis. HOWEVER, imaging findings may overlap

among various soft tissue tumors and might not yield a precise diagnosis.

PRE-OPERATIVE BIOPSY

Role of biopsy is controversial. Risk of potential tumor seeding and complication of

bleeding.

Pre-operative histologic diagnosis is critical in choosing a primary treatment strategy for soft tissue sarcomas.

Provides the best opportunity to evaluate the tumor's proximity to vital structures and the likelihood of being able to perform surgical resection with negative histologic margins.

PRE-OPERATIVE BIOPSY

FINE-NEEDLE ASPIRATION BIOPSY

EUS-guided Acceptable method of diagnosing most soft tissue

sarcomas. Especially useful when results correlate closely

with clinical and imaging findings. Procedure of choice to confirm or rule out the

presence of a metastatic focus or local recurrence.

Diagnostic accuracy: 60 – 96%

21- to 23-gauge needle that is introduced into the mass after appropriate cleansing of the skin and injection of local anesthetic.

Negative pressure is applied, and the needle is pulled back and forth several times in various directions.

After the negative pressure is released, the needle is withdrawn and the contents of the needle are used to prepare a smear.

PRE-OPERATIVE BIOPSY

CORE-NEEDLE BIOPSY Performed if insufficient diagnostic material was

obtained from FNAB.

Safe, accurate, and economical diagnostic procedure for diagnosing sarcomas.

The tissue sample obtained from a core-needle biopsy is usually sufficient for several diagnostic tests such as electron microscopy, cytogenetic analysis, and flow cytometry.

PRE-OPERATIVE BIOPSY

CORE-NEEDLE BIOPSY CT guidance can enhance the positive yield rate

of a core-needle biopsy by more accurately pinpointing the location of the tumor. Precise localization in the tumor mass is particularly

important to avoid sampling nondiagnostic necrotic or cystic areas of the tumor.

CT guidance also permits access to tumors in otherwise inaccessible anatomic locations or near vital structures.

HISTOLOGIC GRADE

Remains the most important prognostic factor for patients with sarcomas.

Shown to predict the development of metastases and overall survival.

Features that define grade: Cellularity Differentiation Pleomorhism Necrosis Number of mitoses

HISTOLOGIC GRADE The number of grade varies according to the

classification system used.

National Cancer Institute Histologic tumor type Location Amount of necrosis

French Federation of Cancer Centers Tumor differentiation Mitotic rate Amount of tumor necrosis

HISTOLOGIC GRADE

2002 American Joint Committee on Cancer staging system

G1: Well differentiated LOW GRADE G2: Moderately differentiated

G3: Poorly differentiated HIGH GRADE G4: Undifferentiated

American Joint Committee on

Cancer Staging

Criteria for Soft Tissue Sarcomas

LIPOSARCOMA

Role of Neo-adjuvant Therapy

NEO-ADJUVANT THERAPY (Pre-operative)RATIONALE:

Only 30 to 50% of patients will respond to standard (postoperative) chemotherapy.

Doxorubicin-based chemotherapy and/or external beam radiation

Identifies disease response to chemotherapy by assessing that response while the primary tumor is in situ.

NEO-ADJUVANT THERAPY (Pre-operative) Patients whose tumors do not respond to short

courses of preoperative chemotherapy are thus spared the toxic effects of prolonged postoperative or adjuvant chemotherapy. Liposarcoma: intermediate sensitivity to chemotherapy

Minimize risk of adverse toxic effects in patients who do not respond to therapy. Neutropenia Thrombocytopenia High-dose doxorubicin

Myelotoxicity, epithelial toxicity, painful "hand-foot syndrome," and potentially severe cardiac toxicity

NEO-ADJUVANT THERAPY (Pre-operative)

Reduce the size or extent of the cancer before receiving surgery. Easier and more successful surgical

procedure

Assessment of therapeutic response to determine the best course of action.

On the 4th hospital day, he undergoes surgery. Operative findings: A 15-cm encapsulated mass is found

located at the retroperitoneum adherent to the ascending colon. The tumor does not involve the aorta nor the inferior vena cava.

Liver is normal Resection of the tumor with R

hemicolectomy is done.

Histopathology of the resected tumor shows the following after special staining:

Postoperative course was uneventful.

Approach to Liposarcoma

Surgery, chemotherapy and radiation. Usually a combination of these options offers

the best chance to successfully treat the disease.

Liposarcoma treatment is planned with two goals in mind: to cure the cancer and to save as much function of the affected area as possible.

Approach to Liposarcoma

• Liposarcoma is, like other soft tissue sarcomas, primarily a surgical disease.

• Surgical objectives include obtaining an accurate histologic diagnosis, minimizing the chance of local recurrence, achieving the best possible functional and anatomic result, and maximizing the probability of survival.

• Most reliably achieved with a wide or radical resection.• Radical local excision because of multiple satellite

nodules.• May follow with postoperative radiation.

Role of Surgery

Open biopsy must be meticulously performed to avoid hematoma, tumor cell spillage, and postoperative infection.

The incision must be oriented so that the biopsy site can be completely encompassed in the definitive resection. A longitudinal incision parallel with the fiber direction of the underlying muscle is used.

Under ideal conditions, the surgeon performing the definitive resection also should perform the initial biopsy. (frozen section)

3 main techniques of surgical resection used in patients with liposarcoma include simple excision, wide en bloc resection, and amputation.

The type of resection used is determined by the tumor's histology and by the anatomic findings at the time of surgery.

Role of Surgery If the lesion appears to be

grossly and histologically consistent with lipoma or well-differentiated liposarcoma, simple excision is acceptable.

If the mass contains areas suggestive of low-grade liposarcoma with clear margins, simple marginal excision can be curative.

When evidence suggesting high-grade liposarcoma is present, either a wider resection of the tumor bed may be performed or adjuvant radiotherapy may be added.

Role of Surgery

If preoperative studies (CT scanning, MRI, biopsy specimen analysis) suggest a high-grade lesion, either wide en bloc resection or amputation can be planned.

Avoid shelling out a high-grade tumor because microscopic disease is left behind.

Types of Surgical Resection

• Intralesional - Partial tumor removal

• Marginal

- May leave microscopic tumor behind• Wide

- Remove tumor and surrounding cuff of normal tissue

• Radical

- Remove entire compartment Includes amputation

Right Hemicolectomy

- large bowel now is attached to the small bowel

Liposarcoma The tumor appears as a

smooth, lobulated, or nodular mass, and in most instances, it is well encapsulated.

Recurrent tumors are not as well encapsulated.

Complete excision is not always possible because of the close association of the tumor with vital structures; therefore, the recurrence rate is high.

Liposarcoma

• Histopathology plays an integral role in the multidisciplinary approach of treating patients with sarcoma,the accuracy of which has important therapeutic implications.

• Intraoperative frozen section consultation is advantageous.

• Indications for frozen section include making a diagnosis, evaluating margin status, determining tumor extent/spread, and obtaining an adequate sample for diagnosis.

Frozen Section

Frozen section evaluation is an essential and reliable procedure for guiding intraoperative decisions.

Intraoperative cytology as an adjunct to frozen section enhances the accuracy of diagnosis of bone and soft tissue lesions.

Cytology can accurately diagnose certain entities alone and is superior to frozen section for certain tumor types and for evaluating bone marrow margins

Can be used to developed or optimize the usefulness of intraoperative pathologic consultation

Frozen Section Cryostat, which is essentially a microtome inside a freezer. Microtome is essentially a very accurate "deli" slicer, capable of slicing

sections as thin as 1 micrometre. Usual histology slice is cut at 5 to 10 micrometres. Surgical specimen is placed on a metal chuck and frozen rapidly to

about −20 to -30 °C. The specimen is embedded in a gel like media known as Optimum Cutting Temperature (OCT) compound.

Usually colder temperature is required for fat or lipid rich tissue, and cooler temperature for skin.

Subsequently it is cut frozen with the microtome portion of the cryostat, the section is picked up on a glass slide and stained (usually with hematoxylin and eosin, the H&E stain).

Preparation of the sample is much more rapid than with traditional histology technique (around 10 minutes vs 16 hours). However, the technical quality of the sections is much lower.

Frozen Section Procedure1. Obtain frozen tissue, preferably frozen in liquid nitrogen. It is imperative that the tissue be frozen as quickly as possible in order

to avoid ice crystal formation resulting in artifact and poor morphological preservation.

2. Make sure the cryostat is at proper operating temperature -20° C to -30° C. Place a small amount of OCT or other suitable frozen section embedding medium on a cryostat object disk (make sure the disk is at room temp. before mounting the specimen).

3. Position the frozen specimen in the center of the object disk and place the disk on the cryobar in the cryostat to begin the quick freeze process.

4. Using "Histo-Freeze" or other appropriate aerosol refrigerant, spray around the periphery of the object disk, as the OCT freezes it will begin to turn from a clear gel to white solid substance. Proceed quickly to step # 5.

5. Before the disk is frozen solid add enough OCT to cover the top the specimen and quickly place a heat extractor on top of the specimen. The heat extractor serves two purposes, (1) rapidly freezes the OCT and tissue and (2) produces a flat embedded surface for easy cutting.

6. Spray with refrigerant if necessary to expedite the freezing process.

7. Place the object disk in the microtome object disk holder and tighten the set screw or clamp.

8. Make sure that there is enough clearance between the block and the microtome knife.

9. Move the block toward the knife edge. Make sure the ratchet is disengaged from the micrometer gear. Turn the flywheel with the right hand and begin turning the gross adjust wheel (on the down stoke) slowly with the left hand. Face off enough OCT until a full section of the specimen is visible.

10. Engage the ratchet on the micrometer gear, cut and discard the first two or three sections.

11. Have the proper fixative (95% ETOH for H&E) and slides ready. Turn the flywheel with the right hand. As the block comes in contact with the knife edge the section will move down the blade and begin to curl. Hold the section down with as little force as possible and guide in along the blade using a camel hair paint brush in the left hand. Continue the cut until a full specimen section has been obtained, but stop before passing through the remaining OCT. One edge of the section is held flat with the paint bush and the other with the knife edge.

12. Pick up the slide with the right hand and turn it so that the top side is facing toward the knife blade.

13. Carefully lower the slide onto the blade, keeping the slide parallel to the section. As the tissue comes into contact with the slide the OCT and tissue will melt causing the tissue to adhere to the slide.

14. Place the slide in fixative. If staining H&E sections, use 95% ETOH and fix for 30 sec.

Surveillance after Initital Surgery Once the tumor has been excised and adjuvant therapy completed,

continued surveillance is required to promptly detect any evidence of local recurrence or distant metastasis.

This typically involves careful physical examination, x-rays of the afflicted limb and serial imaging of the chest and abdomen (usually CT) and pelvis if indicated.

Disease is detected, treatment is rendered accordingly. Consideration for adjuvant therapy for liposarcoma should be based on

the degree of residual disease left behind. Occurence after radiation therapy is radiation-induced sarcoma. By

definition this arises in previously irradiated tissues that were documented to be "normal" prior to radiation. They tend to occur at least 2-3 years after treatment, and may appear up to 30 years later

If microscopic disease remains following surgery, postoperative radiation therapy should be administered.

Eighteen months after surgery, he comes back complaining of persistent cough with weight loss.

Chest x-ray and Chest CT scan are done and show the following:

Chest X-ray 2 years after surgery

Chest CT scan 2 years after surgery

Assessment of Metastases

The lung is the most common site of metastasis for all soft tissue tumors (can also be liver, bone, and brain)

Risk factors for distant metastasis tumor grade, histiotype, primary site, and size.

Most recurrences of soft tissue sarcomas occur in the first 2 years after completion of therapy.

• History and physical examination are the most useful components of follow-up in evaluating for local recurrence after definitive treatment. – Every 3 months postop, first 2-3 years postop

• CT and MRI are useful for evaluating less accessible regions, such as the retroperitoneum– Chest imaging every 6 months, 2-3 yrs post op

• The following should be considered in determining the need for radiographic imaging– Patient characteristics– location of the primary tumor– previous treatment– physician familiarity with changes after surgery and

radiation therapy

Treatment for recurrence

• Complete surgical excision– Selected patients with a limited number of

pulmonary nodules (fewer than four), long disease-free intervals, and no endobronchial invasion may become long-term survivors after pulmonary resection

– Favorable prognostic factors are microscopically free margins, age younger than 40 years, and grade I or II tumors.

• Adjuvant chemotherapy– The only available treatment for most patients with

metastatic disease is chemotherapy

Journal: Diagnosis

CT of Recurrent Retroperitoneal Sarcomas

Background

• The only consistently effective treatment for primary retroperitoneal sarcomas is operative resection

• surgery is curative in only a minority of patients, and primary retroperitoneal

sarcomas have a high rate of recurrence• most effective treatment of recurrent

retroperitoneal sarcomas is additional surgical resection

Objective

By reviewing the medical records and CT scans of 33 patients with recurrent retroperitoneal sarcomas to determine the patterns of recurrent disease

Methodology

• tumor registry database for patients with recurrent

retroperitoneal sarcoma between 1993 and 1998• identified 33 (women, 16; men, 17; age range, 22-

77 years; mean age, 56 years) for whom CT was performed

• recurrent tumor cell type, grade, and location were recorded, and the interval between initial resection and recurrence was calculated. At the time of recurrence, patient symptoms, if any, were identified. The treatment for the recurrence (if any) and the survival rate after treatment was noted

Methodology

• CT scans were evaluated for each of the following: – location of recurrence (subdivided into three

patterns: in or near the original tumor bed, in the abdomen but located outside of the original tumor bed, or at distant extraabdominal sites)

– maximum diameter of the largest recurrence– internal CT attenuation characteristics (the

presence or absence of grossly visualized fat and heterogeneity)

Results

• Resectability of Initial Tumor– some remain positive even after initial impression at

surgery

• Cell Type and Grade of Initial Tumor– most were liposarcomas, followed by

leiomyosarcomas

• Cell Type and Grade of Recurrent Tumor– Myxoid tumor to rhabdomysosarcoma– Liposarcoma to malignant fibrous histiosarcoma– Most were the same grade as before

Results

• Interval Between Initial Resection and Recurrence– Twenty-five (76%) of 33 recurrences were detected within

2 years of initial surgical resection• Symptoms at the Time of Recurrence

– nonspecific consisting of abdominal pain, weight loss and fatigue, fever, and headace. Others complained of abdominal fullness or the sensation of a mass.

• Location of Recurrence– Nonlocal recurrences were found in the mesentery,

peritoneum, retroperitoneum, and liver. One patient with a local recurrence also had distant (lung) metastases

Results

Size of Recurrence several instances, the recurrent tumor was

very small CT Attenuation Characteristics

liposarcomas contained recognizable fat on initial CT scans, only four of the recurrent tumors contained identifiable fat.

Results

Fig. 2. —Bar graph compares interval between initial tumor resection and recurrence for grade I tumors with grade III tumors.

Fig. 1. —Bar graph shows interval between initial tumor resection and recurrence

Discussion

Retroperitoneal sarcomas recur after surgery, patient survival is prolonged only in those with low-grade tumors or in those for whom repeat

surgery can be successfully performed 40% of patients who were disease free at 5

years developed recurrences within 10 years after initial surgery

Discussion

• although some patients with recurrent retroperitoneal sarcomas have distant metastatic disease (usually in the lungs), most have some evidence of recurrence in the abdomen

• radiologists must carefully scrutinize the operative bed and the abdominal cavity in patients for whom a retroperitoneal liposarcoma has been removed. New soft-tissue attenuation masses may represent recurrent tumor, even for patients in whom the primary liposarcomas contained fat

Conclusion

Primary retroperitoneal malignancies frequently recur within 2 years of initial surgical resection. For asymptomatic patients, diagnosis is typically made during routine follow-up CT. Most patients have abdominal recurrences that may be small when first detected

Journal: Treatment

Preoperative Radiation Therapy With Selective Dose

Escalation to the Margin at Risk for Retroperitoneal

Sarcoma

Background

• local recurrence rates approach 50% (compared with 10% for extremity sarcomas treated with surgery and radiation

• aggressive nature of RPS suggests a need for an adjuvant therapy that is both tolerable and effective for local control

• Recently, preoperative intensity-modulated radiation therapy (IMRT) with selective dose escalation has offered a new method of delivering radiation therapy for RPS

Objective

purpose of this prospective, nonrandomized study was to evaluate preoperative IMRT in RPS for complications and local control

Methodology

• 16 consecutive patients with biopsy-proven RPS were treated with preoperative radiation therapy with selective dose escalation to the margin at risk

• primary clinical outcome measures were treatment toxicity and local control. Secondary outcome measures included survival and theoretical calculations of dose escalation

Results

• most common side effect was nausea/vomiting during RT

• Surgery was well tolerated in all 16 patients• There were no wound complications• no instances of severe late postoperative

morbidity or mortality. There were no cases of postoperative (and therefore postradiation) neuropathy, fistulas, obstructions, GU complications, prolonged hospitalizations, or perioperative deaths

Results

Twelve tumors (75%) were found to decrease in maximum dimension by CT. Two tumors (13%) grew in size, with increases of 9% and 36%.

All 16 patients underwent laparotomy, 14 of whom (88%) were able to undergo complete macroscopic resection

Results

5 of the original 16 patients developed disease progression

Three patients who had distant recurrences only at 12 months started with primary tumors

The actuarial local control rate was 80% at 24 months

Results

Results

Discussion

• Although surgery remains the mainstay of treatment for RPS, local failure has remained a problem

• All have encountered the dilemma of finding the appropriately high effective dose while only causing acceptable radiation side effects

• local recurrence problems lie not in the volume in which the tumor sits, but in the surgical margins at risk, especially posteriorly

Discussion

factors for mortality from RPS included presentation stage, high grade, unresectability, and positive macroscopic margins

Conclusion

Preoperative radiation therapy with selective dose escalation to the margin at risk is tolerable and allows higher radiation dose to the volume judged to be at greatest risk for local tumor recurrence

Thank You!