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| SUMMARYPROSPECTUS                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |   |
| PMEGX                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |   |
| May 1,2014                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
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| T. Rowe Price

InstitutionalMid-Cap Equity Growth Fund                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| A fund seeking long-termcapital appreciation through investments in stocks of mid-cap companies and a growth approach to stockselection. The fund is only available to institutional investors.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Beforeyou invest, you may want to review the fund’s prospectus, which contains more information aboutthe fund and its risks. You can find the fund’s prospectus and other information about the fundonline at troweprice.com/prospectus.You can also get this information at no cost by calling 1-800-638-8790 or by sending an e-mail request to info@troweprice.com. This SummaryProspectus incorporates by reference the fund’s prospectus, dated May 1, 2014, and Statement ofAdditional Information, dated May 1, 2014.

The Securities and ExchangeCommission has not approved or disapproved these securities or passed upon the adequacy of this prospectus.Any representation to the contrary is a criminal offense. |
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| Summary | 1      |

Investment Objective

The fund seeks to provide long-term capital appreciation by investingin mid-cap stocks with potential for above-average earnings growth.

Fees and Expenses

This table describes the feesand expenses that you may pay if you buy and hold shares of the fund. 

Fees and Expenses of the Fund

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|---------------------------------------------------------------------------------------------------------------|--------|
| Annual fund operating expenses(expensesthat you pay each year as apercentage of the value of your investment) |
| Managementfees                                                                                                | 0.60%  |
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| Other expenses                                                                                                | 0.01%  |
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| Total annualfund operating expenses                                                                           | 0.61%  |

Example This example is intended to help you compare the cost of investing in the fund with the cost of investingin other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicatedand then redeem all of your shares at the end of those periods. The example also assumes that your investmenthas a 5% return each year and that the fund’s operating expenses remain the same. Although youractual costs may be higher or lower, based on these assumptions your costs would be:

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| 1 year | 3 years | 5 years | 10 years |
| $62    | $195    | $340    | $762     |

Portfolio Turnover  The fundpays transaction costs, such as commissions, when it buys and sells securities (or “turns over”its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may resultin higher taxes when fund shares are held in a taxable account. These costs, which are not reflectedin annual fund operating expenses or in the example, affect the fund’s performance. During the mostrecent fiscal year, the fund’s portfolio turnover rate was 34.1% of the average value of its portfolio.

Investments,Risks, and Performance

Principal InvestmentStrategies  The fund will normally invest at least 80% of its net assets (including any borrowingsfor investment purposes) in a diversified portfolio of common stocks of mid-cap companies whose earningsT. Rowe Price expects to grow at a faster rate than the average company. The fund defines mid-capcompanies as those whose market capitalization (number of shares outstanding multiplied by share price)falls within the range of either the S&P MidCap 400 Index or the Russell Midcap Growth Index. Asof December 31, 2013, the market capitalization ranges for the S&P MidCap 400 Index and theRussell Midcap Growth Index were approximately $717.6 million to $11.5 billion, and $441.7 million to$29.2 billion, 

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| T.Rowe Price | 2      |

respectively. The market capitalization of the companies in thefund’s portfolio and the S&P and Russell indices changes over time; the fund will not automaticallysell or cease to purchase stock of a company it holds just because the company’s market capitalizationgrows or falls outside these ranges.

As “growth” investors, T. Rowe Price believes thatwhen a company’s earnings grow faster than both inflation and the overall economy, the market willeventually reward it with a higher stock price.

In selecting investments, we generally favor companies with oneor more of the following:

· proven products or services;

· a recordof above-average earnings growth;

· demonstrated potential to sustain earnings growth;

· connectionto an industry experiencing increasing demand; or

· stock prices that appear to undervalue their growthprospects.

Inpursuing its investment objective, the fund has the discretion to deviate from its normal investmentcriteria, as previously described, and purchase securities that the fund’s management believes willprovide an opportunity for substantial appreciation. These situations might arise when the fund’smanagement believes a security could increase in value for a variety of reasons, including an extraordinarycorporate event, a new product introduction or innovation, a favorable competitive development, or achange in management.

While most assets will typically be invested in U.S. common stocks, the fund may investin foreign stocks in keeping with the fund’s objectives.

The fund may sell securities for a variety ofreasons, such as to secure gains, limit losses, or redeploy assets into more promising opportunities.

Principal Risks  As with anymutual fund, there is no guarantee that the fund will achieve its objective. The fund’s share pricefluctuates, which means you could lose money by investing in the fund. The principal risks of investingin this fund are summarized as follows:

Activemanagement riskThefund is subject to the risk that the investment adviser’s judgments about the attractiveness, value,or potential appreciation of the fund’s investments may prove to be incorrect. If the securitiesselected and strategies employed by the fund fail to produce the intended results, the fund could underperformother funds with similar objectives and investment strategies.

Risks of stock investing  Stocks generally fluctuate in value more than bondsand may decline significantly over short time periods. There is a chance that stock prices overall willdecline because stock markets tend to move in cycles, with periods of rising prices and falling prices.The value of a stock in which the fund invests may 

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| Summary | 3      |

declinedue to general weakness in the stock market or because of factors that affect a company or a particularindustry. 

Market capitalization risk  Investingprimarily in issuers within the same market capitalization category carries the risk that the categorymay be out of favor due to current market conditions or investor sentiment. Because the fund investsprimarily in securities issued by mid-cap companies, it is likely to be more volatile than a fund thatfocuses on securities issued by large companies. Medium-sized companies typically have less seasonedmanagement, narrower product lines, and less capital reserves and liquidity than larger companies, andare therefore more sensitive to economic, market, and industry changes.

Investment style risk  Different investment styles tend toshift in and out of favor, depending on market conditions and investor sentiment. The fund’s growthapproach to investing could cause it to underperform other stock funds that employ a different investmentstyle. Growth stocks tend to be more volatile than certain other types of stocks and their prices usuallyfluctuate more dramatically than the overall stock market. A stock with growth characteristics can havesharp price declines due to decreases in current or expected earnings and may lack dividends that canhelp cushion its share price in a declining market.

Foreign investing risk  This is the risk that the fund’s investments inforeign securities may be adversely affected by political, social, and economic conditions overseas,reduced liquidity, or decreases in foreign currency values relative to the U.S. dollar.

Performance  The bar chart showing calendar year returns andthe average annual total returns table indicate risk by illustrating how much returns can differ fromone year to the next and how fund performance compares with that of a comparable market index. The fund’spast performance (before and after taxes) is not necessarily an indication of future performance.

Thefund can also experience short-term performance swings, as shown by the best and worst calendar quarterreturns during the years depicted.

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| T.Rowe Price | 4      |

In addition, the average annualtotal returns table shows hypothetical after-tax returns to suggest how taxes paid by a shareholder mayinfluence returns. After-tax returns are calculated using the historical highest individual federal marginalincome tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns dependon an investor’s tax situation and may differ from those shown. After-tax returns shown are notrelevant to investors who hold their fund shares through tax-deferred arrangements, such as a 401(k)account or individual retirement account.

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|-----------------------------|----------------------------------------------------------------------------------|--------------------------------------|-------------------|--------|-------------|---------------|-------------|-------------|----------------|--------|--------|--------|
| AverageAnnual Total Returns |                                                                             |                                 |              |   |        |          |        |        |           |   |
|                        |                                                                             |                                 | Periods ended     |   |
|                        |                                                                             |                                 | December 31, 2013 |   |
|                        |                                                                             |                                 | 1 Year       |   |        | 5 Years  |        |        | 10 Years  |   |   |   |
|                        | Institutional Mid-Cap Equity GrowthFund                                          |                                 |              |   |        |          |        |        |           |   |   |
|                        |                                                                             | Returns before taxes                 | 37.89        | %      | 24.21  | %             | 11.78  | %           |           |
|                        |                                                                             | Returns after taxes on distributions | 36.70        |   |        | 23.86    |        |        | 10.93     |   |   |   |
|                        |                                                                             | Returns after taxes on distributions |              |   |        |          |        |        |           |   |   |   |
|                        |                                                                             | and sale of fund shares              | 22.39        |   |        | 20.02    |        |        | 9.71      |   |   |   |
|                        | Russell Midcap GrowthIndex (reflects no deduction for fees, expenses, or taxes)a | 35.74                           |              |   | 23.37  |          |        | 9.77   |           |   |   |
|                        | S&P MidCap 400 Index (reflects no deductionfor fees, expenses, or taxes)     | 33.50                           |              |   | 21.89  |          |        | 10.36  |           |   |   |

a EffectiveOctober 1, 2013, the fund’s primary benchmark for performance comparison purposes was changed fromthe S&P MidCap 400 Index to the Russell Midcap Growth Index. The new primary benchmark better reflectsthe performance of the fund’s growth-oriented investment universe.

Updated performance information is available through troweprice.comor may be obtained by calling 1-800-638-8790.

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| Summary | 5      |

Management

Investment Adviser T. Rowe Price Associates, Inc. (T. Rowe Price)

|                |                                        |               |                      |
|---------------------|---------------------------------------------|--------------------|---------------------------|
| Portfolio Manager   | Title                                       | Managed Fund Since | Joined Investment Adviser |
| Brian W.H. Berghuis | Chairman of Investment

 Advisory Committee | 1996               | 1985                      |

Purchaseand Sale of Fund Shares

Subject to certain exceptions, the fund is currently closed to new investors and newaccounts. Investors who currently hold shares of the fund may continue to purchase additional shares.

Thefund generally requires a $1,000,000 minimum initial investment. There is no minimum for subsequent purchases.If you hold shares through a financial intermediary, the intermediary may impose different investmentminimums.

Youmay purchase, redeem, or exchange shares of the fund on any day the New York Stock Exchange is open forbusiness by calling 1-800-638-8790 or by written request. If you hold shares through a financial intermediary,you must purchase, redeem, and exchange shares through your intermediary.

Tax Information

Anydividends or capital gains are declared and paid annually, usually in December. Distributions by thefund, whether or not you reinvest these amounts in additional fund shares, may be taxed as ordinary incomeor capital gains unless you invest through a tax-deferred account. A redemption or exchange of fund sharesmay be taxable. 

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| T. Rowe PriceAssociates, Inc.100 East Pratt StreetBaltimore, MD 21202 | E116-0455/1/14 |